Fruits & vegetables Technology

FRUITS AND VEGETABLES TECHNOLOGY NotesPreparedBy: - Mohit Jindal Page 1 of 101
FRUITS AND VEGETABLES TECHNOLOGY
1. Introduction (03 hrs)
Status and scope of fruits and vegetables industry in India, classification, composition and nutritive value of
fruits and vegetables
2. Preparatory Operations and Related Equipments (05 hrs)
Cleaning, sorting, grading, peeling and blanching methods
3. a) Ingredients and processes for the manufacture of: (08 hrs)
i) jam, jellies, marmalade, preserves, (ii) pickles and chutneys
b) Defects and factors affecting the quality of above
4. Tomato Products (04 hrs)
Ingredients and their role, process for the manufacture of tomato ketchup, sauce, puree and paste.
5. Juices (04 hrs)
Raw materials, extraction, classification, processing and aseptic packaging
6. Thermal Processing of Fruits and Vegetables (08 hrs)
History, definition, various techniques of thermal processing and their effects on the quality of fruits
and vegetable products, types of containers and their selection, spoilage of canned foods
7. a) Dehydration of fruits; equipment and process for dehydration of plums, apricot, apple, fig,
grapes peach etc (04 hrs)
b) Dehydration of Vegetables: equipment and process for dehydration of peas, cauliflower,
potato, methi, mushroom, tomato etc
c) Osmo-dehydration – basic concept and applications
8. Freezing (04 hrs)
Freezing process of selected fruits and vegetables: peas, beans, cauliflower, apricot, mushroom –
changes during freezing and spoilage of frozen foods
9. Food Laws and FPO standards for fruits and vegetable products (04 hrs)
10. By-products utilization (04 hrs)
LIST OF PRACTICALS
1. Orientation to different processing equipments, their functions and uses
2. Preparation of Jam, jelly and preserve
3. Preparation of pickle by various methods

4. Preparation of chutney
5. Extraction of tomato juice by hot and cold break methods
6. Preparation of tomato sauce/ketchup
7. Preparation of tomato puree/paste
8. Extraction of juice by various methods
9. Bottling and processing of fruit juice
10. Preparation of syrup and brine solutions
11. Dehydration of peas, potatos
12. Dehydration of grapes and apples
13. Freezing of peas
14. Preparation of tomato powder
15. Visits to different fruit and vegetable processing industries
Status and scope of fruits and vegetables industry in India, classification, composition and nutritive
value of fruits and vegetables

India is the second-largest producer, next to China, of fruit and vegetables in the world, contributing
a total of 150 million tonnes of the produce to the global production annually. But only 2.2% of the fruit and
vegetable are processed here as compared to countries like USA (65%), Philippines (78%) and China (23%).
That’s why there is a huge opportunity for companies looking at investing in this sector in the country.
Although India is a very large producer of fruits, but yield levels of most of the fruits are relatively low as
compared to those in other major fruit producing countries. India is a front runner in many fruits and
vegetables with share in world production (Indian Horticulture Database 2013) as follows:
 44.1% of mango
 42.6% Papaya
 25.6% of banana
 20.2% of onion
 35.6% of cauliflower
About 25 to 30 per cent of the total production is lost due to spoilage at various post-harvest stages. In
value terms, the post harvest wastage and losses per year are estimated at over Rs. 3000 crores. Because of
these losses, the per capita availability of fruits is only of the order of 75 gm per person per day, which is
just half of the requirements of a balanced diet. This happens due to:
1. Lack of Transport
2. Lack of Storage facilities
3. Poor availability of package materials
4. Poor road conditions
5. Lack of local cold storage to store the surplus
43.0 45.2 45.9 50.9 55.4 59.6
65.6 68.5 71.5 74.9 76.4
88.6 84.8 88.3
101.2
111.4
115.0
128.4 129.1
133.7
146.6 156.3
0
50
100
150
200
250
VEGETABLES
FRUITS
(Production in Million Tonnes)
Trends in Fruits and Vegetables Production
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This results in the inadequate pricing of produce during off season and spoilage. This provides the
farmer to gain a higher price on his product, due to palatability of the product.
The major fruits grown are banana, mango, citrus, guava, grapes, apple and pineapple which
constituted nearly 80 per cent of the total fruit production in the country. Banana has the largest share of

31.7 per cent in total fruit production, followed by mango with 28 per cent. Production of mango has
remained almost stagnant during the decade 1983-93. The annual growth in production during 1983-93 was
9.6 per cent in the case of banana, 10.3 per cent for papaya, 9.4 per cent for grapes and 4.7 per cent in
respect of citrus fruits. The major fruit producing states are Andhra Pradesh, Maharashtra, Karnataka, Bihar,
Uttar Pradesh, Tamil Nadu, Kerala and Gujarat. These eight states contribute 78 per cent of the total fruit
production.
The Indian gourmet food market is currently valued at US$ 1.3 billion and is growing at of 20 per
cent. It is expected to cross US$ 2.8 billion by 2015 and is expected to reach US$ 78 billion by 2018. Share
of online food ordering would be in single digits of the overall food ordering business which in 2014 was
estimated to be around Rs 5,000-6,000 crore (US$ 800.19-960.12 million). We are growing at 20-30 per
cent month-on-month.
The total food production in India is likely to double in the next 10 years with the country’s domestic
food market estimated to reach US$ 258 billion by 2015.
Consumption pattern
Out of the total production of fruits and vegetables, nearly 76 per cent is consumed in fresh form,
while wastage is around 20 to 22 per cent. Only 2 per cent of vegetable production and 4 per cent of fruit
production are being processed.
Processing facilities
It is significant to note that the current installed capacity can process only 3 to 4 per cent of their total
production of fruits and vegetables in the country. There were around 4100 to 4200 processing units licensed
with an installed capacity of 12 lakhs tonnes. The actual production in 1993 was only 5.6 lakhs tones
implying a capacity utilization of less than 50per cent. Being seasonal in nature, the units operate for less
than 150 days in a year.
Exports
The government has initiated several policy measures for encouraging exports of processed fruits
and vegetables. As a result, exports of these products have increased from Rs. 122.5 crores in 1990/91 to Rs.
332.4 crores in 1993/94.
India’s share in word exports of fresh and processed fruits and vegetables was quite insignificant
being just 1 per cent. India’s major exports are in fruit pulp, pickles, chutneys, canned fruits and vegetables,
concentrated pulps and juices, dehydrated vegetables and frozen fruits and vegetables.
India has the potential to achieve a 3% share in the world trade of agricultural and food products by
2015. The vast production base offers India tremendous opportunities for export. During 2013-14, India
exported fruits and vegetables worth Rs. 8760.96 crores which comprised of fruits worth Rs. 3298.03 crores
and vegetables worth Rs. 5462.93 crores.
Demand
The demand for processed fruits and vegetables comes from both the domestic and export markets.
In the domestic market, a substantial share is contributed by defence, hotels and restaurants. Household
consumption accounts for less than 50 per cent of the production. India’s exported are constrained by several
factors such as poor quality, lack of standardization and unattractive packaging.

Government
It is evident that there is considerable scope for expansion of processing of fruits and vegetables. Indian
government is striving hard to build a strong fruit and vegetable processing industry to sustain its market
share in the global market. Indian Government to promote food-processing industry and also its sub-sector
like fruit and vegetable processing industry in India. Indian government has considered for investing US $
22.97 million in establishing around 10 mega food parks and offered the tax benefits to the concerned sub-
sector of the food processing industry. The present fruits and vegetables processing scenario compared to the
developed countries is not satisfactory. The factors responsible for this are many and complex in nature.
 The basic problem associated with the industry is the sustained availability of suitable raw material
for processing. Moreover, the productivity is also very low as compared to many other countries. The
cost of raw material used for processing is 3 to 4 times more as compared to costs in the world
market.
 With the increasing competition from the international trade, quality of imported products will
become more available in the developing countries. Therefore, to compete, the developing countries
require proper post harvest management, distribution and processing chains. Hence, it is necessary to
have better human resource capabilities in technology, management and marketing.
 Policies like participation of private sectors through contract farming and land leasing arrangement
can assure supply of good quality raw material to the fruit and vegetable processing industry.
 Clustering of small and medium units can reduce cost of production.
 It is very vital to educate consumer about the processed fruit and vegetable based products and their
nutritional quality.
 It is imperative to have better linkages between fruit and vegetable processing industry, Government
and other institutions.
 Should have control over taxation with other nations during export and import of the processed fruit
and vegetable products.
 It is necessary to integrate food laws, which is expected to meet the requirements in the International
trade and make the Indian food industry competitive in the global market.
Scope
There is tremendous production of fruits and vegetables in a shorter period. Availability of cheap labour,
Government Subsidy for cold storage and processing units, convenience of roads in case for marketing and
transport. Availability of cans, bottles, and other equipments at cheap rate, there is tremendous for export of
processed products like Jam, jelly, marmalade, pickles, etc. dehydrated and dried vegetables in addition to
domestic demand in India. Five-year tax holiday for new food processing units in fruits and vegetables
processing along with other benefits in the budget has bolstered the government’s resolution of encouraging
growth in this sector.
A vegetable is an herbaceous plant cultivated for an edible part, such as the root of the beet, the leaf
of spinach, or the flower buds of broccoli or cauliflower. The botanical term vegetable refers to any plant,
edible or not, including trees, bushes, vines and vascular plants, and distinguishes plant material from
animal material and from inorganic matter.

There are two slightly different botanical definitions for the term vegetable as it relates to food.
According to one, a vegetable is a plant cultivated for its edible part(s); according to the other, a vegetable is
the edible part(s) of a plant, such as the stems and stalk (celery), root (carrot), tuber (potato), bulb
(onion), leaves (spinach, lettuce), flower (globe artichoke), fruit (apple, cucumber, pumpkin, strawberries,
tomato) or seeds (beans, peas).
Edible plant parts including stems and stalks, roots, tubers, bulbs, leaves, flowers and fruits; usually
includes seaweed and sweet corn; may or may not include pulses or mushrooms; generally consumed raw
or cooked with a main dish, in a mixed dish, as an appetizer or in a salad There are many numbers of
Vegetables. Different parts are used for consumption. They are botanically different and their climatic and
cultural requirements are different.
There are four Main Methods of Classification Based on:
1. Education Botanical relation
2. Based on Hardiness (Tolerance to low temp)
3. Parts Used for consumption
4. Methods of Culture
1. Botanical Classification:
This method of classification is based on botanical relationships. Classification based on the
plants botany is the favored method for plant botanists, taxonomists and breeders. It gives information on
class, family, genus, species, variety etc. Some plants do however have similar cultural requirements the
most notable of these is the Solanaceae and Cucurbitaceae families. This is useful to crop improvement and
seed producer for deciding isolation distance. Solanaceous family includes potato, chili. There are same
cultural requirements. At the same time cucurbitaceous have similar cultural requirements and common
pests and diseases. Botanical name avoids infusion in name as common names are different but scientific
names are common all over would.
2. Classification Basedon Hardiness:
Vegetables are grouped as hardy or tender on the basis of tolerance to frost, tolerance to lower temperature.
This gives information of season of growing i.e. summer or winter. Not useful to grower, since soil and
climatic requirements are
Hardy
Semi Hardy Tender
Asparagus Beet Root Okra
Cabbage Carrot Brinjal
Garlic Cauliflower Tomato / Chili
Onion Palak Beans
Peas Potato Cucurbit
Radish Sweet Potato
Spinach Sweet Potato
Spinach Amaranthus
Turmp
3) Basedon Parts Usedfor Consumption:
From roots to fruits different parts of vegetables are consumed. On that basis vegetables are classified.
Leafy Vegetable Palak, Amaranthus Methi (leaves)

Root Carrot, Radish, Turnip', beet root
Fruit Tomato, Biinjal; Cucurbit,
cucumber, olives
Bulb Onion, Garlic
Tuber Potato, Sweet Potato
Podded Green bean, Moth Bean, Mung
Bean,
Steam Asparagus, Cardoon,
Celery(Ajvayan), Fennel(Sonf)
Flower cauliflower, Broccoli
Leaf Vegetables Also known by the name, ‘potherbs’, leafy vegetables are plant leaves that are eaten as a
vegetable. Leafy vegetables have high nutritional value though it is the presence of Vitamin K.
Fruit vegetables are so called because botanically they fulfill the definition of fruits, but are used as
vegetables by human beings. They are considered to be fruits because in the scientific sense of the term,
fruits are those that carry the seeds of the plant. Legally, the confusion between whether these vegetables
should be called fruits or vegetables was solved in the United States by the Supreme Court in the year 1883
where tomato was declared as a vegetable.
Bulb vegetables are those varieties of vegetables that are not eaten directly on their own, rather, they are
used in food dishes to enhance the flavor of the food. Most of the bulb vegetables are structured in the shape
of a bulb, wherein all its nutrients are stored. The best known bulb vegetables are onion, chive, spring onion
and garlic. These bulb vegetables are said to be medicinal, especially onion and garlic.
Podded vegetables, popularly known as legumes, are seeds that are found inside two-sided pods. Podded
vegetables are a rich source of proteins which help in providing the energy and strength required to carry out
daily activities. They also contain potassium, folic acid, complex carbohydrates, magnesium, iron, fibre and
zinc
Root vegetables are those that are grown under the soil and possess nutrients that they gain from the soil.
They are actually, storage organs that are enlarged to store energy in the form of carbohydrates.
Stem vegetables are those that have shoots or stalks which can be consumed. Some of the most popular
stem vegetables include asparagus, celery, fennel, etc. These vegetables can be used to make a variety of
dishes and are usually served with pasta, sandwiches, soups, etc.
Flowering vegetables are so called because they have the shape of flowers. They are usually small in size
and appear like many flower buds clustered together.
Tubers grows underground, it is a type of specialized stem tissue that stores nutrients for the plant. A potato
is actually an enlarged stem. Root crops derive from root tissue. Carrots are an enlarged tap root. Tubers
differ from root crops in three ways. Tubers are enlarged stems rather than enlarged roots. Cut up a tuber,
and each section will grow a plant; root crops cannot do this. Tubers contain more starch than root crops.
4) Basedon Method of Culture:
In this method all those crops having similar cultural requirements are grouped together. They" are
botanically different. System has practical utility for vegetable grower. In this method one can generalise

cultivation practices for one group and thus avoid repetition individually for all crops. There are 11 classes.
In some cases they are botanically also similar Ex. cucurbits. On excises for convenience they are grouped
as under.
I. Perennial Vegetable Asparagus, cocinia (Tondali), Parwal, Drumstick
2 Greens Spinach
3 Salad Crops Lettuce, celery
4 Cole Crops Cabbage, Cauliflower
5 Bulb Crops Onion, Garlic
6 Root Crops Carrot / radish, turnip
7 Tuber a) Potato, b) Sweet Potato
8. Peas & Beans Cluster bean, cowpea, Dolichas
9 Solanaceous Tomato, Brinjal, Chili,
10 Cucurbits Watermelon, pumpkin, gourds, Cucumber etc.
11 Okra Okra
Composition and nutritive value of vegetables
Vegetables have a low energy value. They generally provide between 10 Kcal and 50 Kcal per 1 g;
to obtain about 1000 Kcal, it would be necessary to eat about kg. Their nutritional advantage is that they
offer a high concentration of micronutrients for low contents of calories and fat. All vegetables have a high
water content, which ranges from 9% in potato to 96% in cucumber. They vary in chemical composition
even within one variety, depending on the species, conditions of growth, and method of cooking.
Vegetables are generally rich in carbohydrates but not in proteins and lipids. Vegetables are
composed chiefly of carbohydrates, mainly simple sugars and complex carbohydrates (starch and dietary
fiber). The content ranges from 1-2% in the leaf and stem vegetables to 27% in sweet potato. Root
vegetables have the highest carbohydrate content. Dietary fiber content ranges from 0.8% in cucumber to
8.0% in artichoke.

Most vegetables contain substantial amounts of minerals, particularly calcium, iron, and potassium. All
vegetables contain small amounts of the B-complex vitamins, but their nutritive value is mainly derived
from the supply of ß-carotene, vitamin C, and folic acid. Although most vegetables contribute to the
formation of vitamin A, their ß-carotene content varies and is generally linked to color. All vegetables
contain substantial amounts of vitamin C, but the quantity varies and much of it is lost during cooking and
preparation. The exact nutrient content of fresh vegetables off the shelf cannot be determined because of a
high degree of variation. Sources of variation include genetic potential, crop growth and cultural conditions,
maturity at harvest, postharvest handling and storage conditions, and type as well as degree of processing.
Fruit
Broadly, the botanical term fruit refers to that a fruit is
defined as the developed ovary of a seed plant with its contents
and accessory parts, as the pea pod, nut, tomato, or pineapple. It
is the edible part of a plant developed from a flower, with any
accessory tissues, as the peach, mulberry, or banana.
But As related to food, the botanical term fruit refers to
the edible part of a plant that consists of the seeds and
surrounding tissues. This includes fleshy fruits (such as blue-
berries, cantaloupe, poach, pumpkin, tomato) and dry fruits,
where the ripened ovary wall becomes papery, leathery, or woody as with cereal grains, pulses (mature
beans and peas) and nuts.
As the ovary develops into a fruit, its wall often thickens and becomes differentiated into three, more
or less, distinct layers. The three layers together form the pericarp, which surrounds the developing seed or
seeds.
The three fruit layers are:
 Exocarp—the outermost layer often consisting of only the epidermis
 Mesocarp—or middle layer, which varies in thickness
 Endocarp—which shows considerable variation from one species to another, is the inner-most layer
of the fruit

FRUITS AND VEGETABLES TECHNOLOGY NotesPreparedBy: - Mohit Jindal Page 10 of
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Fruit Classification
All fruits may be classified into three major groups on the basis of the number of ovaries and the number of
flowers involved in their formation. The following outline includes most of the common types of fruits.
A. Simple Fruits—simple fruits develop from a single matured ovary in a single flower. Accessory
fruits have some other flower part united with the ovary. There are two basic kinds of simple fruits:
fleshy fruits and dry fruits.
1. Fleshy Fruits—defined as having a fleshy pericarp at maturity. There are five basic kinds of fleshy
fruits.
 Berry—consisting of one or more carpels with one or
more seeds, the
ovary wall is
fleshy.
Examples of
berries include:
grape, tomato
 Pepo—an accessory fruit is defined as a berry with a hard rind, the receptacle partially or completely
encloses the ovary. Examples include: Watermelon, honeydew melon, cucumber, Pumpkin
 Hesperidium—a specialized berry with a leathery rind. Examples include: Orange, lemon, grapefruit
 Drupe—sometimes called a “stone” fruit. It is derived from a single carpel and usually containing
one seed (pit). The exocarp of a drupe consists of a very thin skin. Examples of the drupe include:
Peach, Apricot, Plum, Coconut (fibrous walls instead of fleshy walls), Cherry

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 Pome—(an accessory fruit) is derived from several carpels, receptacle and outer portions of the
flower. The pericarp is fleshy with an inner portion of the pericarp papery or cartilaginous forming a
core where the seeds are located. Examples of a pome are: apple, pear
2. Dry Fruits—are defined as having a dry pericarp upon maturity. The Dry Fruits are classified into
two groups: the dehiscent fruits and the indehiscent fruits.
(a) Dehiscent Fruits—these fruits will split open when mature. The splitting process is
known as “dehisce”…hence the name for this group of fruits. There are four basic types
of dry dehiscent fruits:
 Follicles—composed of one carpel and splitting along one suture line. Examples of follicle
fruits are: Columbine, Milkweeds
 Legumes—composed of a single carpel and splitting along two suture lines. Examples of
legumes are: Peas, Peanuts
 Capsule—composed of several carpels. Examples of the capsule type fruits: Lily, Sweet Gum
 Silique—composed of two carpels. Examples of the silique fruit: Members of the Mustard
Family

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(b) Dry Indehiscent Fruits—are defined as fruits that do not split open at maturity. There are
several categories of dry indehiscent fruits.
 Achene (or sometimes called an akene)— Examples of achenes are: Dandelion parachutes,
Sunflowers
 Caryopsis or Grain—is defined as a one-seeded fruit in which the seed is firmly attached to
the fruit at all possible points. Examples of grain include: Corn, Rice, Wheat, All grasses
 Samara—We sometimes refer to this type of fruit as “helicopter” seeds. Examples include:
Elms, Maples, Ashes
 Schizocarp—Examples of schizocarp fruits are: apiaceaes
 Nut—a hard one-seeded fruit, generally formed from a compound ovary, with the pericarp
hard throughout. Examples of true nuts are: acorns, chestnuts, walnuts, pecans brazil nut
B. Aggregate Fruits—consist of a number of matured ovaries formed in a single flower and arranged
over the surface of a single receptacle. The individual ovaries of the aggregate fruit are known as
fruitlets. Each individual fruitlet will contain a stony pit…so in reality an aggregate fruit is
composed of many tiny drupes. Examples of aggregate fruits are:
1. Raspberries
2. mulberries
3. strawberries
C. Multiple Fruits—consist of the matured ovaries of several to many flowers more or less united into a
mass. Multiple fruits are almost invariably accessory fruits. Examples of multiple fruits are:
1. Pineapples
2. Jackfruit

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3. Breadfruit
Composition and nutritive value of fruit
The carbohydrates in fruit have a moderate energy value. Fruit contain protective vitamins and
minerals, and dietary fiber but very little protein. They are practically fat-free except for avocado and olive,
both of which contain up to 15% of fat. Fruit vary widely in their carbohydrate content (between 1.5% and
26 %).
Ripe fruit contain no starch; the main sugars are fructose and glucose which are often present in
equal proportions. Apple and pear contain more fructose, while apricot and peach also contain sucrose. Like
vegetables, fruit also contain dietary fiber. Various organic acids in unripe fruit produce the typical sour
taste. During ripening concentration of these acids falls and that of sugars rises.
Vitamin C is present in all fresh fruit, but strawberry, citrus fruit and particularly kiwifruit are
outstanding sources of this vitamin. For example, one kiwifruit or medium-size orange supplies the normal
daily requirement of adults. Apple and peach provide moderate amounts of vitamin C and can contribute
substantially to the diet when consumed in sufficient quantity.
Most fruit also supply varying amounts of ß-carotene and the B-complex vitamins. Yellow fruit, such
as cantaloupe and apricot, are good sources of vitamin A, whereas plum and dried fruit (those not treated
with sulphur dioxide) are the best sources of thiamin.
Fruit contribute appreciable amounts of iron and calcium. Calcium is found in small amounts in
citrus fruit; the whole fruit contains double the amount contained in an equal quantity of juice. Strawberry
and dried fig also contains calcium. As in the case of vegetables, careful preparation and storage are
essential to retain the maximum nutritive value of fruit. Some of the nutritive value is lost during cooking,
drying, and canning, but the losses are not as high as they were once supposed. Frozen fruit compare
favorably in vitamin content with fresh ones. Bruising and cutting of fruit, and exposing fruit and fruit juices
to air cause considerable loss of vitamin C.

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Preparatory Operations andRelatedEquipments-Cleaning, sorting, grading, peeling and
blanching methods
The preliminary preparative operations in food processing include cleaning, sorting and grading of
food raw material. These may be considered as separation operation. Cleaning involves the separation of
contaminants from the desired raw materials. Sorting involves the separation of the raw materials
into different categories based on their physical characteristics such as size, shape and colour.
Grading involves the separation of the raw materials into categories based on the differences in their
overall quality.
CLEANING OF FOOD RAW MATERIALS
Cleaning is an essential preliminary operation in any food industry. The ultimate quality of the finished
product, storage stability, organoleptic properties, safety from health hazards, and consumer acceptance
depend on cleaning process. The methods adopted depend on the type of raw material, type and extent of
contamination, the degree of cleaning to be achieved and the type of finished product. Different food raw
materials are associated with different types of contaminants. These include
 Mineral contaminants- soil, sand, stone metallic particles, grease and oil.
 plant part- stalks, pits, husks and rope,
 Animal parts and contaminants—excreta, hair, insects eggs and body part
 Chemical contamination- sprayed residues of pesticides, insecticides and fertilizers
 Microbial contaminants—microorganisms and their metabolites.
The two main objectives of cleaning food raw materials are
1. Removal of contaminants which constitute a health hazard or which are aesthetically unacceptable
2. Control of microbiological loads and biochemical reactions which impair subsequent process
effectiveness and product quality.
The chosen cleaning process must satisfy the following requirements in order to achieve the aforesaid
objective:-
1. The separation efficiency of the process must be high and consistent and should produce minimum
wastage of good material
2. Damage of cleaned raw material must be avoided.
3. Recontamination of the cleaned food should be avoided by complete removal of the contaminants.
4. The design of the process equipment should be such that recontamination of the cleaned food due to
flying dust or wash water is prevented.
5. The cleaning process must leave the cleaned surface in acceptable condition,
6. The volume and concentration of liquid effluents must be kept be minimum and the effluents should
be disposed off effectively Complete cleaning of a raw material is not possible and in practice, a
balanced approach, considering the economic aspects of cleaning and the need to produce good
quality food, is usually adopted,
Cleaning Methods
The cleaning methods can be classified into two groups, namely

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 Dry cleaning methods which include screening, brushing, aspiration, abrasion and magnetic
separation
 Wet cleaning methods which include soaking, spraying, flotation, ultrasonic cleaning, filtration and
settling.
Dry cleaning methods
These methods are relatively cheap and convenient as the cleaned surface is dry However, a major drawback
is the spread of dust.
Screening-Screens are primarily size separators or sorting machines but may be used as cleaning
equipment for removing contaminants of different size from that of the raw material. These machines are
useful in cleaning fine materials such as flour and ground
spices but must be frequently cleaned to remove oversized
contaminants which may otherwise get pulverized due to
abrasion and spread contamination of the raw material.
Abrasion cleaning- Abrasion between food
particles or between the food and moving parts of cleaning
machinery is used to loosen and remove adhering
contaminants. Tumblers, vibrators, abrasive discs and
rotating brushes are used for this purpose.
Aspiration cleaning- Aspiration (or
winnowing) is based on the differences in the
aerodynamic properties of materials. The raw
material to be cleaned is fed into a stream of air
flowing at controlled velocity to separate the raw
materials into two or more streams (e.g. light and
heavy streams). The cleaned products are usually
discharged as the middle stream leaving the heavy
debris (stones, pieces of metal or wood) behind
while floating off the light debris such as stalks,
husks and hairs. This method is used in cleaning
cereals, nuts, beans, onions, melon, eggs and other
foods which are not amenable to wetting.
The method cannot be used with
oxidation-sensitive materials.
Magnetic cleaning- This type of
cleaning involves where the food
contaminated with high amount of
metallic material. Magnetic separators
used for this type of cleaning include

101
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rotating or stationary magnetic drums, magnetized belts, magnets located over belts carrying the food or
staggered magnetized grids through which the food is passed.
Miscellaneous dry cleaning methods- Such cleaning methods include:
1. Electrostatic cleaning
2. radio isotope separation
3. X-ray separation.
Electrostatic cleaning- Electrostatic cleaning can be used in a limited number of cases where the
surface charge on raw materials differs from contaminating particles. The principle can be used to
distinguish grains from other seeds of similar geometry but differences in electrostatic charging of materials
under controlled humidity conditions, charged particles being removed by oppositely charged or earthed
rollers, grids, etc. and it has also been described for cleaning tea. The feed is conveyed on a charged belt and
charged particles are attracted to an oppositely charged electrode according to their surface charge.
Radio isotope separation- Clods of earths and stones may be separated from the potatoes.
X-ray separation- Stones, gloss and metal fragments in foods such as confectionery can be
separated by this method.
Wet cleaning methods-
Wet cleaning has the advantage of removing firmly adherent soils and owing the use of detergents
and sanitizers. However, wet methods have a number of disadvantages such as the use of large amounts of
high quality water and generation of large volume of effluent (about 15,000 liters per ton of canned food).
Wet cleaning methods include soaking, spray washing, flotation washing and ultrasonic cleaning methods.
Soaking- This is the simplest method and is often used as preliminary stage in the cleaning of heavily
contaminated root vegetables and other foods. Soaking softens adhering soil and also facilitates the removal
of sand, stone, and ether abrasive material. The use of warm water and detergents increase the efficiency but the
use of chemicals may affect the texture of the food, e.g, sodium hexametaphosphate softens peas while some metal ions
toughen peas and peaches destined for canning, Chlorination is used to decrease bacterial load of water in the soak
tank.

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Spray washing. This is the most widely used method for wet cleaning of fruits and vegetables.
The surface of the food is subjected to water sprays, The efficiency of spray washing depends on
several parameters such as water pressure, volume of water, temperature, the distance of the food from
jets, the time of spraying and number of spray jets used. A small volume of water at high pressure is the
most effective combination. High pressure sprays may be used to cut out parts of peaches and tomatoes
and to remove adherent soil and black moulds on citrus fruits. It may damage ripe fruits and vegetables
such as straw berries and tomatoes and delicate vegetables such as asparagus.
The washer is equipped with a central spray rod which is fitted with jets for spraying water.
A rubber disc cleaner requires less amount of water for cleaning. It uses soft rubber discs
spinning axially at about 500 rpm. The soil is collected into the base of the channel. The disc cleaner
uses only about 20 liters of water per ton of fruit while other washers use 1500-5000 litres.
Flotation washing- The method depends on the differences in buoyancy of the desired and
undesired parts of the food raw material to be cleaned. For example, bruised or rotten apples sink in
water and can be removed at the base of tank and the good fruit can be collected as overflow. The
flotation washer effectively removes stones, dirt and plant debris from peas, beans, dried fruits and
similar materials. Water requirement is about 4,000-10,000 liters per ton of raw material to be
cleaned.
Froth flotation has been used to separate peas from weed seeds by immersing the peas in dilute
mineral oil-detergent emulsion through which air is blown, the contaminants float on foam and are
removed. The cleaned peas are given a final wash to remove the emulsion.

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Dewatering- Wet cleaning results in a cleaned product that may have some excess water adhering
to it. Dewatering may be effected by passing the food over vibratory screens or specially designed
rotary screens. In the case of cleaned peas for freezing, or washed wheat for milling, centrifuges may
be used. Occasionally it may be necessary to resort to drying procedures, as in the case of cereals or
fruits, which arc to be stored or sold as fresh.
SORTING OF FOODS
Sorting and grading are terms which are frequently used interchangeably in the food
processing industry, but strictly speaking they are distinct operations.
Sorting is a separation based cm a single measurable property of raw material units,
while grading is the assessment of the overall quality of a food using a number of attributes".
Sorting may be regarded as a separation operation based on the differences in physical properties of
the food raw materials or products such as colour, size, shape or weights of the food raw material.
Sorting is an important operation in controlling the effectiveness of many processes in food
industry. For example, sorted vegetables and fruits are better suited for mechanized operations of
peeling, pitting and coring or blanching. Similarly, food materials of uniform size or shape are better
suited for efficient heat transfer during sterilization, pasteurization, dehydration or freezing.
Sorting and grading can both damage the food raw material or product because of improper
handling by human operators (operator damage), dumping (dumping damage) or dropping of material
(drop damage). Such damages can be eliminated or minimized by choosing effective food process.
Sorting Methods
Sorting methods include weight sorting, shape sorting, size sorting and photometric or colour sorting.
Weight sorting- Weight is usually the most precise method of sorting. The weight of a food
unit is proportional to the cube of its characteristic dimension and hence weight sorting is more
precise compared to dimensional sorting. Meat cuts, fish fillets, fruits such as apples, pears and citrus
fruits, vegetables such as potatoes, carrots and onions and eggs are sorted by weight using spring-
loaded, strain gauge, or electronic weighing devices incorporated into conveying systems.. An
alternative system is to use the "catapult' principle where units are thrown into different collecting
section, depending on their weight. A disadvantage of weight sorting is the relatively long time
required per unit and other methods are more appropriate with smaller items such as legumes or
cereals, or if faster throughput is required.
.

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Size sorting- Different types of screens are used for size separation of foods, The screen
designs commonly used in food industry may be grouped into two types: (i) variable aperture screens
using cable, belt, roller or screw sorters and (ii) fixed aperture screens using stationary, vibratory,
rotary, gyratory or reciprocating screens. Fixed
aperture screens of flat-bed type are used in
preliminary sorting of potatoes, carrots and
turnips. Multi-deck screens are used in size
sorting of cereals, nuts and also partly
processed and finished foods such as flour,
sugar, salt, ground spices and herbs. Drum
screens are used for sorting peas, beans and
other similar foods capable of withstanding
tumbling action in a rotating drum screen.
Variable aperture screens with continuously
variable apertures of roller, belt or screw type find use in size sorting of fruits and vegetables.

101
Shape sorting- Shape sorting is adopted when food raw materials contain undesirable material even
after size or weight sorting and cleaning. For example, cleaned and size or weight sorted wheat may
still contain weed seeds of similar size and weight compared to wheat. Shape sorting on the basis of a
combination of length and diameter is useful under such circumstances. A disc sorter is used for
shape sorting wheat, rice, oats and barley. The principle is that disks or cylinders with accurately
shaped indentations will pick up seeds of the correct shape when rotated through the stock, while
other shapes will remain in the feed.
Photometric/Color sorting- Photometric sorting uses optical properties of foods to effect
separation of desired material from contaminants. The goal is the separation of items that are
discolored, toxic, not as ripe as required, or still with hull. The color separator separates the fruits,
vegetables or grains due to difference in color or brightness. The color separators are generally used
for larger crop seeds like peas and beans. These seeds differ in color because of varietal differences
and also due to immaturity or disease. Color sorters are also used for color sorting harvested
foodstuffs, such as coffee, nuts, rice, and other cereals such as wheat or rye and pulses.
Two photocells are fixed at a particular angle, which direct both beams to one point of the
parabolic trajectory of the grains. A needle is placed on the other side, which is connected to a high
voltage source. When a beam falls on a dark object through photoelectric cells, current is generated
on the needle. The needle end receives a charge and imparts it to the dark seeds. The grains are then
passed between two electrodes with a high potential difference between them. The seed is compared
with a selected background or color range, and is separated into two fractions according to difference
in color. Since this machine views each produce individually, the capacity is low.
Reflectance properties are used to indicate:
1. Raw material maturity (e.g. color of fruit, vegetables and meat indicates ripeness and
freshness characterize ;)
2. the presence of surface defects (e.g. worm holed cereals or nuts and bruised fruits)

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3. The extent of heat processing (e.g. in manufacture of bread and potato chips or crisps).
Other sorting methods- Sorting on the basis of surface roughness or stickiness may be used for
separating seeds. In Surface Texture/Roughness Separator the mixture to be separated is fed over the centre
of an inclined draper belt moving in upward direction. The round and smooth grains roll or slide down the
draper at faster rate than the upward motion of the belt, and these are discharged in a hopper. The flat shape
or rough surfaced particles are carried to the top of the inclined draper and dropped off into another hopper.
GRADING OF FOODS
Grading is quality separation on the basis of an overall assessment of those properties, which affect the
acceptance of the food raw material for processing, and finished food product for consumer acceptance and
safety. The grading factors which determine the quality of the food include:
1. Process suitability
2. consumer safety
3. Consumer acceptance.
The grading parameters commonly used in food industry include the following:
 size and shape as functional and acceptability factors,
 maturity to describe the freshness of eggs, ripeness of fruits and aging of meat,
 texture to grade the crumb structure in bread and cakes, crispness in apples and viscosity of
creams
 flavour and aroma as indicators of ripeness of fruits as well as effectiveness of processing
conditions,
 colour as indicator for consumer acceptability and effectiveness of process,

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 Blemishes such as cloudy yolk, blood spot and shell cracks in eggs, bruises in fruits and insect
holes in coffee beans and cereals to indicate their defect and impurity.
Contaminants and undesired parts such as rodent hair and insect parts in flour, soil and spray residues on
fruits and vegetables, microorganisms and their metabolites on meat, toxic metals in shell fish, hone
fragments in meat products, pod residues in peas and beans and stalks and stones in fruits all these are the
adverse qualities of the raw food materials.
Grading Methods
Grading methods may be classified into two types:
 Quality control procedures in which the quality of the food is determined by laboratory tests on
samples drawn statistically from a batch of food.
 Procedures in which the total quantity of food is subjected to physical separation in quality
categories. This grading may be carried out manually or by specialized machines.
For proper grading, the food unit must be presented singly before the human grader or machine for
assessment. These devices may be roller or vibratory tables or rotating wheels equipped peripherally with
pneumatic devices which pick up food pieces, rotate them for viewing and then release them at a given
signal.
Manual grading is done by trained operators who are able to assess a number of grading parameters
simultaneously. For example, eggs are graded manually by candling.
. Machine grading is only feasible where quality of a food is linked to a single physical property, and
hence a sorting operation leads to different grades of material. But can be carried out by combining a group
of sorting operations so as to separate the food units on quill it basis. Thus wheat of a particular variety may
be graded by a combination of cleaning and sorting operations. Sometimes a single property may be helpful
in grading the food. Thus peas of small size are recognized to be most tender and of highest quality so that
size sorting of cleaned peas results in quality grading. Peas may also be graded on the basis of their density
using flotation in brines of varying densities. Similarly, potatoes or high density, desirable for manufacturing
French fries, potato crisps and dehydrated mashed potato, may be graded using Rotation in brines.
Mechanical grading is cost effective and efficient.
Peeling
Peeling is used in the processing of many fruits and vegetables to remove unwanted or inedible material, and
to improve the appearance of the final product. The main consideration is to minimise costs by removing as
little of the underlying food as possible and reducing energy, labour and material costs to a minimum. The
peeled surface should be clean and undamaged. There are five main methods of peeling:
1. flash steam peeling
2. knife peeling
3. abrasion peeling
4. caustic peeling
5. flame peeling.
Flash steam peeling

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Foods (for example root crops) are fed in batches into a pressure vessel which is rotated at 4–6 rpm.
High-pressure steam is introduced and all food surfaces are exposed to the steam by the rotation of the
vessel for a predetermined time, which differs according to the type of food. The high temperatures cause
rapid heating of the surface layer (within 15–30 s) but the low thermal conductivity of the product prevents
further heat penetration, and the product is not cooked. Texture and colour are therefore preserved. The
pressure is then instantly released which causes steam to form under the skin, and the surface of the food
‘flashes off’. Most of the peeled material is discharged with the steam, and water sprays are needed only to
remove any remaining traces. This type of peeler is gaining in popularity owing to the lower water
consumption, minimum product loss, good appearance of the peeled surfaces, a high throughput (up to 4500
kg h_1) with automatic control of the peeling cycle, and the production of a more easily disposable
concentrated waste.
Knife peeling
Stationary blades are pressed against the surface of rotating fruits or vegetables to remove the skin.
Alternatively the blades may rotate against stationary foods. This method is particularly suitable for citrus
fruits where the skin is easily removed and there is little damage or loss of fruit.
Abrasion peeling
Food is fed onto carborundum rollers or placed into a rotating bowl which is lined with
carborundum. The abrasive surface removes the skin and it is washed away by a copious supply of water.
The advantages of the method include low energy costs as the process operates at room temperature, low
capital costs, no heat damage and a good surface appearance of the food. Irregular product surfaces (for
example ‘eyes’ on potatoes) may mar the appearance of the peeled product and require hand finishing. The
limitations of the method are:
• a higher product loss than flash peeling (25% compared with 8–18% losses, for vegetables)
• the production of large volumes of dilute waste which are difficult and expensive to dispose of
• relatively low throughputs as all pieces of food need to contact the abrasive surfaces.
An exception is the peeling of onions where the skin is easily removed by abrasive rollers at production rates
of up to 2500 kg h_1.

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Caustic peeling
A dilute solution of sodium hydroxide (named lye) is heated to 100–120ºC. In the older method of
lye peeling, food is passed through a bath of 1–2% lye which softens the skin and the skin is then removed
by high-pressure water sprays. Product losses are of the order of 17%. Although once popular for root crops,
this method causes changes in the colour of some products and incurs higher costs. It is now largely replaced
by steam or flash peeling. A development of lye peeling is named dry caustic peeling. Food is dipped in
10% sodium hydroxide and the softened skin is removed with rubber discs or rollers. This both reduces
water consumption and product losses and gives a concentrated skin ‘paste’ which is more easily disposed
of.
Flame peeling
Developed for onions, this peeler consists of a conveyor belt which carries and rotates the food through a
furnace heated to 1000ºC. The outer ‘paper shell’ and root hairs are burned off, and the charred skin is
removed by high-pressure water sprays. Average product losses are 9%.
Blanching
Partial pre-treatment in which fruits or vegetables are heated in water or in steam to
inactivate enzyme before processing.
Blanching is done by immersing fruits and vegetables in hot water or by exposing to steam
followed by cooling.
Blanching is a partial pre-cooking treatment in which vegetables/ fruits are usually
heated in water or in live steam to inactivate the enzymes before processing.
Blanching is a unit operation applied to fruits and vegetables prior to canning, drying or
freezing. Blanching is a mild type of heat processing. It involves heating food to preset temperature
for preset time. It is usually done in water or steam at a temperature less than 100°C. Prepared fruits
and vegetables is kept in hot water or exposed to steam and then cool rapidly to ambient temperature.
Blanching is used to destroy microorganism and enzymatic activity in fruits and vegetables.
Blanching caused inactivation of enzymes in canning, freezing and dehydration, because freezing and
dehydration are insufficient to inactivate enzymes. Sometimes canning process may allow sufficient
time for enzymatic activity. And under blanching may increase the enzymatic activity.
There are four types of enzymes such as lipoxygenase, polyphenololase, polygalacturonase and
chlorophyllase, which causes loss of quality in fruits and vegetables, must be inactivated. Because at
lower temperature time the enzyme chlorophyllase remains active for little time and convert
chlorophyll to a phyllin, which retain green colour. The enzymes such as catalase and peroxidase are
heat resistant, which need appropriate time and temperature to inactivate them.
Blanching also reduces the number of microorganisms..
Purpose of blanching
• Reduces drying time

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• Removes intercellular air from the tissues
• Causes softening of texture
• Retards the development of objectionable odour and flavour during storage by enzyme inactivation
• Retain carotene and ascorbic acid during storage
• Removes pungency (onion)
• Impart desired translucent appearance to the product.
Different blanching methods:
Blanching can significantly reduce the nutrient content of foods. The extent of losses of nutrient is
dependent on the blanching method and the product.
1. Immersion
2. Steaming
Immersion
Immersion blanching refers to blanching by directly immersing the food particles in boiling
water. This treatment has number of advantages and disadvantages. In water blanching the loss of
water –soluble vitamins increases with contact time, and fat – soluble vitamins are relatively
unaffected and also risk of contamination and higher cost of water and disposal of effluent than
steam blanchers. Sometimes certain additives may be used in blanching water to complement
blanching. For instances, addition of citric acid (0.5%) to immersion bath decreases pH. Addition of
bisulfite (0.5%) prevents mushroom browning and yellowing of cauliflower. Blanching is quickly
followed by a cooling stage. This is done by cooling the product under cool water to bring down its
temperature. Rapid cooling avoids microbial growth on the exposed surfaces..
Steaming
Blanching by steaming has the advantage of minimizing the leaching out of soluble materials,
less volume of waste, easy to clean and sterilize. Steam Blanching results in greater retention of
water – soluble nutrients than water blanching. But it has some disadvantages i.e. higher capital
costs, uneven blanching, and low efficiency However, at the same operating temperature, steam
blanching takes 20-40% longer than immersion blanching because of poor thermal exchange.

101
(d) it has adverse environmental impacts, such as large water and energy use and problems of
effluent disposal.
Process Equipment
Rotary hot water and steam blanchers are common process equipment and are respectively. They are
available with variable speed drive.
The rotary hot water blancher receives the product through a valve just above the drive end.
The product is conducted into a spiral unit which conveys it to the opposite end.
In the case of the hooded live steam blancher which has a perforated wire belt, the blancher
serves as a conveyor making it very adoptable to the system. The steam blancher consists of a metal
frame with galvanized sheet metal forming the steam chamber. The unit is frequently equipped with
both water and steam sprays to increase its versatility as a scolder/blancher. The lower belt of the
hooded chamber is pitched to a separate drain outlet for removal of condensate.
A typical commercial steam blancher is approximately 20 ft. long, 4 ft. wide and 4 ft. high. A
typical water blancher would be around 6 ft. in height with an overall length of 21 ft. In general
Disadvantages of Blanching
The disadvantages of blanching are that
(a) it may change texture, color, and flavor because of the heating process,
(b) it increases the loss of soluble solids, especially in the case of water blanching,
(c) it may change the chemical and physical state of nutrients and vitamins,

101
steam blanching results in greater retention of water-soluble nutrients due to less leaching loss.
The advantages of steam blanchers are: smaller loss of water soluble components, smaller
volume of waste, lower disposal charges and easy to clean and sterilize.
The disadvantages associated with a steam blanchers are: limited cleaning of food, higher
capital cost, uneven blanching, some mass loss in food and poor energy efficiency.
At the same time, the advantages of hot water blanchers are lower capital cost and better
energy efficiency. The disadvantages are loss of water soluble components, higher cost of water
and disposal of effluent and risk of contamination. A thermal screw may also be used to steam blanch
products. Here, the product is conveyed in a trough by a closely fitting helical screw. Steam injected
at regular interval is used to heat the product. Similar designs use hot water as the transfer medium,
and this reduces abrasion and damage to sensitive products such as mushroom.
We should select a size of blancher which will handle the line capacity without being over crowded.
As an operator, we have to ensure maintenance of the unit on a regular basis and check that
automatic controls are performing well. The use of a check thermometer to ascertain the accuracy of
the one installed on the unit is a good practice..

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Ingredients and processesfor the manufacture of: i) jam, jellies, marmalade, preserves,
(ii) pickles and chutneys b) Defects and factors affecting the quality of above
FRUIT JAM
Jam: Jam is prepared by boiling whole fruit pulp with cane sugar (sucrose) to a moderately thick
consistency with out retaining the shape of the fruit. As per FPO specification 45 parts of fruit to each 55
parts of sugar and contain 0.5-0.6% acid and invert sugar should not be more than 40%. is used for
preparation of jam.
Or
Jam is a product with reasonably thick consistency, firm enough to hold the fruit tissues in position,
and is made by boiling fruit pulp with sufficient sugar.
Preparation of Jam
Jam can be prepared from one kind of fruit or from two or more kinds. It may be made from
practically all varieties of fruit. Apple, papaya, carrot, strawberry, mango, grapes, pineapple, etc. are used
for the preparation of jams. Various combinations of different varieties of fruit can be often made to
advantage, pineapple being one of the best for blending purposes because of its pronounced flavour and
acidity.
1. Selection of fruit: Fruit should be in right proportion which gives good quantity of pectin and also
natural flavour. For this fully ripped and ripped fruit are used in right proportion.
2. Preparation of fruit pulp: Sound fruit is sorted, washed in running water or, preferably, brush-
washed and prepared. The mode of preparation varies with the nature of the fruit. For example,
mangoes are peeled, steamed and pulped; apples are peeled, cored, sliced, heated with water and
pulped; plums are scalded and pulped; peaches are peeled and pulped; apricots are halved, steamed
and pulped; berries are heated with water and pulped or cooked as such.
3. Addition of sugar: To make jams and jellies, up to a maximum of 25% of corn syrup for sweetness
can be utilized. Generally, cane sugar of good quality is used in the preparation of jams. The
proportion of sugar to fruit varies with type and variety of fruit, its stage of ripeness and acidity. A
fruit pulp to sugar ratio of 1:1 is generally followed. This ratio is usually suited to fruits viz., berries,
currants, plums, apricots, pineapple and other tart fruits.
4. Addition of acid: Citric, malic or tartaric acids are present naturally in different fruits. These acids
are also added to supplement the acidity of the fruits deficient in natural acids during jam making.
Addition of acid becomes necessary as adequate proportion of sugar- pectin- acid is required to give
good set to the jam. The recommended pH for the mixture of fruit juice and pectin is 3.1. The acidity
of finished jam varies between 0.5 to 0.7 % depending on the type of the jam. It is often advisable to
add acid at the end of cooking which leads to more inversion of sugar. When acid is added in the
beginning, it will result in poor set.

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5. Processing/boiling: Fruit pulp is cooked with the requisite quantities of sugar and pectin, and
finished to 69% Total Soluble Solids (TSS). Permitted food colours, requisite amount of citric acid
and flavourings are added at this stage. The boiling process, in addition to excess water removal, also
partially inverts the sugar, develops the flavour and texture. During jam boiling, all microorganisms
are destroyed within the product. When this is filled hot into clean receptacles which are
subsequently sealed, and then inverted the hot jam contacts the lid surface, thus prevents the spoilage
by micro-organisms during storage.
6. Judging of End Point
Concentration of jam is finished at an optimum point avoiding over cooking which leads to
economic losses due to less yield. But under cooking will result in the spoilage of jam during storage
due to fermentation. The finishing or end point of jam can be determined by the following methods.
 Drop test: This method is the simplest way and commonly
used by housewives where no other facilities are available. In this method, a
little quantity of jam is taken from the boiling pan in a tea spoon and allowed
to air cool before putting a drop of it in a glass filled with water. Settling
down of the drop without disintegration
denotes the end point
 By sheet test: In this test, a
small portion of jam is taken with a large
spoon or wooden ladle, cooled slightly and then allow to
drop off keeping the spoon or ladle in horizontally inclined
position. If the jam drops like syrup, further concentration
is needed. If it is in the form of flake or forms a sheet, the
finishing point is attained
 Refractometer method: This is the most common
method used by small and large scale fruit
processing industries for jam making. The cooking
is stopped when the refractometer shows 69 oBrix.
 Boiling point method: Jam containing 69% TSS
boils at 106 oC at sea level. This method is simplest and best to determine the finishing point
of jam.
 By weighing method: Weighing method is more laborious and time consuming. Here the
boiling pan is weighed before and again after transferring the extract and sugar in to it. The
end point is attained when the net jam weight is one and a half times of the quantity of sugar
added.
 Packaging The product is packed in cans or glass jars, and cooled, followed by labeling and
packaging. Containers including can or jar gets sterilized when hot jam (not less than 85oC)
is poured in them. Boiling the containers in hot water can also effect sterilization.
Special Care/ Problems in Jam Production
1. Crystallization: The final product should contain 30–40% invert sugar. If the
percentage is less than 30, cane sugar may crystallize out on storage and if it is more
than 50 the jam will become a honey-like mass due to high inversion of 40 % sugar
into glucose. Corn syrup or glucose may be added along with cane sugar to avoid
crystallization.

101
2. Sticky or gummy jam: Because of high percentage of total soluble solids, jams tend
to become gummy or sticky. This problem can be solved by addition of pectin or
citric acid, or both.
3. Premature setting: This is due to low total soluble solids and high pectin content in
the jam and can be prevented by adding more sugar. If this cannot be done a small
quantity of sodium bicarbonate is added to reduce the acidity and thus prevent pre-
coagulation.
4. Surface graining and shrinkage: This is caused by evaporation of moisture during
storage of jam. Storing in a cool place can reduce it.
5. Microbial spoilage: The mould attack on jam can be eliminated by storing them at
less than 90% RH (Preferably at 80% RH). It is also advisable to add 40 ppm
sulphur dioxide in the form of KMS. In the case of cans, sulphur dioxide should not
be added to the jam as it causes blackening of the internal surface of the can.
FRUIT JELLY
Jelly: Jellies are gellified products obtained by boiling fruit juices with sugar, with or without the addition of
pectin and food acids.
OR
Jelly is a semi solid product prepared by boiling a clear, strained solution of pectin containing fruit extract,
free from pulp, after addition of sugar and acid.

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A jelly is a semisolid product prepared by boiling fruit with water, expressing as water (pectin) extract),
adding sugar, and concentrating to such consistency that gelatinization takes place on cooling. A perfect
jelly should be transparent, well set, but not too stiff, and should have the original flavour of the fruit. It
should be of attractive colour and keep its shape when removed from the mould. It should not be gummy,
sticky, or syrupy or have crystallized sugar.
Preparation of Jelly
Selection of fruits: Guava, sour apple, plum, papaya, certain varieties of banana and gooseberry are
generally used for preparation of jelly. Other fruits can also be used but only after addition of pectin powder,
since these fruits are low in pectin content. Fruits can be divided into four groups according to their pectin
contents. This classification is highly useful in preparation of jelly, because pectin is the important
component, which is responsible for the texture of the jelly. The classification is as follows.
1. Rich in pectin and acid: sour apple, grape, lemon, sour oranges, jamun, sour plum.
2. Rich in pectin but low in acid: apple, unripe banana, pear, ripe guava, etc.
3. Low in pectin but rich in acid: sour apricot, sweet cherry, sour peach, pineapple and strawberry.
4. Low in pectin and acid: ripe apricot, peach, pomegranate, strawberry and other over ripe fruits.
Extraction of pectin/boiling: After selection, the fruits are washed thoroughly. Most of the fruits are boiled
for extraction of the juice in order to obtain maximum yield of juice and pectin. Boiling converts protopectin
into pectin and softens fruit tissues. Very juicy fruits do not require the addition of water and are crushed
and heated to boiling only for 5 min. Firm fruits are cut or crushed and boiled with water for 5 min. The
length of boiling will vary according to the type and texture of fruit. The amount of water added to the fruit
must be sufficient to give a high yield of pectin e.g. apples require one half to an equal volume of water,
where as citrus fruits require 2-3 volumes of water for each volume of sliced fruits.
Straining and clarification: Pectin extract is obtained by straining the boiled fruit mass through bags made
of linen, flannel, or cheese cloth folded several times. For large scale production, the fruit extract is made to
pass through filter presses for clarity.
Analysis of extract: Clarified extract is analysed for pH, acidity, soluble solids and pectin content by
common laboratory methods.
 For determining pectin content the easiest way adopted is precipitating the pectin with alcohol. A
rapid test for evaluation of juice pectin content is by mixing a small sample of juice with an equal
volume of 96% alcohol in a tube. The mixture from the tube is then emptied on a plate. The
appearance of a compact gelatinous precipitate indicates sufficient pectin content for jellification
(Figure J-1). Insufficient pectin will remain in numerous small granular lumps

101
.
Figure J-1 .4: Pectin test for jelly extract. a) Low pectin extract; b) High pectin extract
Addition of sugar and pectin: Based on the pectin test of the fruit extract, quantity of sugar to be added is
worked out. For the extract rich in pectin, sugar equal to the quantity of the extract is added. To the extract
with moderate pectin 650 – 750 g of sugar should be added to each kg of extract. For juices rich in pectin,
jellification will occur without pectin addition. If pectin content is less, 1-2% powder pectin will be added to
the juice.
Addition of acid: Jelly strength increases with increasing hydrogen ion concentration until an optimum pH
is reached which is generally 3.2 at 65%sugar concentration. Jellying strength depends on the quantity of
pectin and the acid present in the original fruit extract.
Processing/boiling: The juice is boiled up to remove about half of the water that has to be evaporated. Then
the calculated sugar quantity is added gradually. The remainder of the water is evaporated until a TSS
(refractometric extract) of 65% is reached. During boiling it is necessary to remove foam / scum formed.
Product acidity must be brought to about 1% (malic acid) corresponding to pH > 3. Any acid addition is
performed always at the end of boiling. Boiling of jellies is performed in small batches (25-75 kg) in order
to avoid excessively long boiling time which brings about pectin degradation.
Judging of End Point
Boiling of jelly should not be prolonged, because excessive boiling results in greater inversion of sugar and
destruction of pectin. The end point can be judged by sheet test, drop test, refractometry, thermometer, and
by weighing the boiling mass. Methods like sheet test, drop test, and weighing of the boiling mass can be
done in the similar way as in the case of jam preparation.
 Refractometer method: This is the most common method used in fruit processing industries for jelly
making. The cooking is stopped when the refractometer shows 65o Brix.
 Temperature test: A solution containing 65% TSS boils at 105oC. Heating of the jelly to this
temperature would automatically bring the concentration of solids to 65%. Endpoint of finishing
jelly should be 4.5-5oC higher than that of the boiling point of water at that place.
Packaging
After jelly is ready, it is skimmed to remove foam. It is cooled slightly before pouring into dry and hot glass
jars. Cooling is optional and is carried out up to 85oC, in double wall baths with water circulation. Filling is
performed at a temperature not below 85oC in receptacles (glass jars, etc.), which must be maintained still
for about 24 hours to allow cooling and product jellification.

101
Problems in Jelly Making
The most important difficulties that are
experienced are as follows:
• Failure to set: This may be due to the addition
of too much sugar, lack of acid or pectin,
cooking below/ beyond the end-point.
• Colour changes: Darkening at the top of the
jars can be caused by storing them in too warm
place or by an imperfect jar seal.
• Gummy jelly: It is the result of prolonged or
over cooking in which more than desired
inversion of sugar occurs
• Stiff jelly: Over cooking or using too much
pectin makes too tough jelly which fails to
spread when applied on bread.
• Cloudy or foggy jellies: It is due to the use of
non-clarified juice or extract, use of immature
fruits, over-cooking, over-cooling, non-removal
of scum, faulty pouring, and premature gelation.
• Formation of crystals: It is due to addition of
excess sugar and also due to the over-
concentration of jelly. This excess sugar comes
from over cooking, too little acid or from under
cooking.
• Syneresis or weeping of jelly: The
phenomenon of exudation of fluid from a gel is
called syneresis or weeping and is caused by several factors. The factors include; excess of acid, too low
concentration of sugar, insufficient pectin, premature gelation, and fermentation
• Presence of mold: Due to imperfect sealing and insufficient sugar.
• Colour fading: This is due to high temperature and bright light in storage room. Another possible cause
could be the insufficient processing to destroy the enzymes affecting colour or the elevated processing
temperature, which might cause colour fading. Trapped air bubbles can also contribute to the chemical
changes by oxidation.

101
MARMALADE
Marmalade is a fruit jelly in which slices of the fruit or its peel are suspended.
OR
Marmalade is a clear jelly in which shreds of peel are suspended. It is generally prepared from citrus fruits
Marmalade preparation is similar to jelly with the difference that it contains citrus fruits like oranges and
lemons in which shredded peel is used as the suspended material. In the preparation of marmalade bitterness
is regarded as desirable characteristic of product. The principles of jelly making, apply also to the
preparation of marmalade Marmalades are classified into two:
1. jelly marmalade
2. jam marmalade
Jelly Marmalade
Good quality jelly marmalade can be prepared from a combination of Sweet orange/ Mandarin
orange and sour orange in a 2:1 proportion. Shreds of sweet orange (Malta) peel are used in the
preparation.
1. Selection of fruit-Sound, ripened fruit is sorted, washed, and prepared. The mode of preparation
varies with the nature of the fruit. The fruits are then cut in to slices and are boiled for the
preparation of extract.
2. Extraction of pectin/boiling: After selection, the fruits are washed thoroughly. Most of the fruits are
boiled for extraction of the juice in order to obtain maximum yield of juice and pectin. Boiling
converts protopectin into pectin and softens fruit tissues. The amount of water added to the fruit must
be sufficient to give a high yield of pectin e.g. apples require one half to an equal volume of water,
where as citrus fruits require 2-3 volumes of water for each volume of sliced fruits.
3. Straining and clarification: Pectin extract is obtained by straining the boiled fruit mass through bags
made of linen, flannel, or cheese cloth folded several times. For large scale production, the fruit
extract is made to pass through filter presses for clarity
4. Analysis of extract: As like Jelly.
5. Preparation of peel shreds: The outer layer of yellow portion of citrus fruits is peeled off carefully.
The stripped-off peel is cut into slices of about 2-2.5 cm long and 1-1.2 mm thick. Boiling in water
with 0.25% sodium bicarbonate or 0.1% ammonia solution can soften the shreds. Before addition to
the jelly, the shreds may be kept in heavy syrup for some time to increase their bulk density to avoid
floating on the surface when it is mixed with jelly.
6. Addition of sugar and pectin: Based on the pectin test of the fruit extract, quantity of sugar to be
added is worked out. For the extract rich in pectin, sugar equal to the quantity of the extract is added.
To the extract with moderate pectin 650 – 750 g of sugar should be added to each kg of extract. For
juices rich in pectin, jellification will occur without pectin addition. If pectin content is less, 1-2%
powder pectin will be added to the juice.
7. Addition of acid: Jelly strength increases with increasing hydrogen ion concentration until an
optimum pH is reached which is generally 3.2 at 65%sugar concentration. Jellying strength depends
on the quantity of pectin and the acid present in the original fruit extract.
8. Processing: During boiling, the impurities in the form of scum are occasionally removed. When the
temperature of the mixture reaches 103oC, the prepared shreds of peel are mixed in it at the rate of 5-
7% of the original extract. Boiling is continued till the end point is reached. The end point is judged

101
in the same way as in the case of jelly. Like jelly, marmalade also contains 65% TSS at 105oC.
Boiling should not prolong for more than 20 min, after the addition of sugar to get bright and
sparkling marmalade.
9. Cooling: The marmalade is cooled to permit the absorption of sugar by the shreds from the
surrounding syrup. If the marmalade is filled in hot, the shreds may come to the surface instead of
remaining in suspension. During cooling, the product is gently stirred occasionally for uniform
distribution of shreds. When marmalade temperature reaches around 85oC, viscosity of syrup
increases and a thin film begins to form on surface, which prevents shreds from coming to surface.
10. Flavouring: This is done by adding some flavour or orange oil to the product near the end of boiling
to supplement the flavour lost during boiling. Generally, a few drops of orange oil are mixed in
marmalade before filling into containers.
11. Packaging and Storage: Like jams and jellies, marmalade is also filled into jars and cans at a
temperature around 850C. Storage of marmalade must be done in dry rooms (relative humidity at
about 75%), well ventilated, medium cool places (temperature 10-20oC), disinfected and away from
direct sunlight and heat. These measures are necessary because marmalade is a hydroscopic product
and, by water absorption, favorable conditions for mould development are created.
Jam Marmalade
Jam marmalade is practically made by the method used for preparation of jelly marmalade except that the
pectin extract is not clarified. The orange peel after removing albedo portion is sliced into 0.3 cm thick
pieces and treated in the same way as recommended for jelly marmalade. The sliced fruit of orange, lemon,
or grape fruit after removing peel is mixed with little quantity of water and boiled to soften. The boiled
mixture is pressed through coarse pulper to remove seed and to get thick pulp. The pulp is mixed with equal
quantity of sugar and cooked to a consistency of 65o Brix or consistency of jam. The treated shreds are
mixed in the jam when it is slightly cool. Some orange oil is also mixed in the marmalade before filling into
containers. Filling and packaging is done in the similar way as adopted for packaging of jelly and jelly
marmalade.
Problems in Marmalade Making
Browning during storage is very common which can be prevented by the addition of 0.09g of potassium
metabi-sulphite (KMS) per kg of marmalade and not using tin containers. KMS dissolved in a small quantity
of water is added to the marmalade while it is cooling. KMS also eliminates the possibility of spoilage due
to moulds.

101
PICKLES
Pickle is an edible product preserved in a solution of common salt and vinegar. It is one of the
most ancient method of preserving fruits and vegetables. Pickles are good appetizers and add to the
palatability of meal. They stimulate the flow of gastric juice and thus help in digestion. Several kinds
of pickles are sold in Indian market. Mango pickle ranks first. Pickles can also be prepared from
fruits and vegetables like lemon, amla, onion, cauliflower, cabbage, beans, cucumber, bitter gourd,
jackfruit, turnip etc. Fruits are generally preserved in sweetened and spiced vinegar, while vegetables
in salt.
Pickling Process
The preservation of food in common salt or in vinegar is called pickling. Pickling may also be
the result of fermentation by lactic acid forming bacteria, which are naturally present in large
numbers on the surface of fresh vegetables and fruits. These bacteria can grow in acid medium and in
the presence of 8- 10% salt solution, whereas the growth of majority of undesirable organisms is
inhibited. Lactic acid bacteria are most active at 30oC, so this temperature should be maintained, as
far as possible, in the process of pickling. Pickling is done in two stages.
Stage I can be done by any of the three following methods :
i) Fermentation with dry salting,
ii) Fermentation in brine, or
iii) Salting without fermentation.
Stage II is finishing and packing.
Fermentation with Dry Salting
In this method, the vegetable is treated with dry salt. The salt extracts the juice from the vegetables
and forms the brine, which is fermented by lactic acid bacteria. The method of dry salting in general
is as follows:
1. The vegetable is washed, drained, weighed for preparing pickles.
2. Several alternate layers of the prepared vegetable and salt (20-30 g of dry salt/ kg vegetables)
are kept in a vessel which is covered with a cloth and a wooden board and allowed to stand for
24 hrs. During this period brine is formed by osmosis. As soon as the brine is formed, the
fermentation process starts and the CO2 begins to evolve.
3. When fermentation is over, gas formation stops. Under favorable conditions fermentation is
completed in 8-10 days, however in cold weather it may take 2 to 4 weeks. When sufficient
lactic acid has been formed, lactic acid bacteria stop to grow and no further change takes
place in vegetables.

101
4. Precaution should be taken against spoilage by aerobic microbes, because in the presence of
air “pickles scum”, a kind of wild yeast, is formed which brings about putrefaction and
destroys the lactic acid.
5. The product may be preserved and kept by excluding air.
Fermentation in Brine
In this method steeping of the vegetables in brine, it penetrates in the tissues of the vegetables
and soluble material present in vegetable diffuses into the brine by osmosis. The soluble material
includes fermentable sugars and minerals. The sugars serve as food for lactic acid bacteria, which
convert them into lactic and other acids. The acid brine thus formed acts upon vegetable tissues to
produce characteristic taste and aroma of pickle. The amount of brine required is usually half the
volume of vegetables. Brining is the most important step in pickling. The growth of the majority of
spoilage organisms is inhibited by brine containing 15% salt. Lactic acid bacteria are salt-tolerant
and can grow in brine of 8-10% strength. In a brine containing 10
% salt, fermentation precedes somewhat slowly so 5 % brine used for fair fermentation. Fermentation
takes place to some extent up to 15 % but stops at 20% brine strength. After fermentation process,
the salt content is now increased gradually, so that by the time pickle is ready, salt concentration
reaches 15%.
Salting Without Fermentation
In this type of process vegetables are washed, prepared and is mixed with salt (250 g/kg of prepared
material). This high salt concentration will inhibit the fermentation. After curing of Vegetables with
large amount of salt they are drained and excess of salt is removed by soaking them in cold or warm
water. Thereafter, the vegetables are stored in plain vinegar of 10% strength for several weeks.
Vegetables can also be stored in sweetened and spiced vinegar. The spices can be added in the
ground form or essential oil of spices may be added to impart the spice flavour.
VARIOUS PICKLES
At present, pickles are prepared with salt, vinegar, oil or with a combination of above ingredients
with spices. These methods are discussed below:
Preservation with Salt

101
Salt improves the taste and flavour and hardens the tissue of vegetables and controls fermentation.
Salt content of 15% or above prevents microbial spoilage. This method of preservation is generally
used only for vegetables, which contains very little sugar. Since the sugar content is less, sufficient
lactic acid cannot be formed by fermentation to act as preservative. However, some fruits viz.,
mango, lemon, etc. are also preserved with salt. An example for pickle preparation with salt is shown
Mangoes (Matured green)
↓
Washing
↓
Peeling
↓
Slicing
↓
Putting slices in jar
↓
Sprinkling salt
↓
Putting in sun for one week
(shaking jar at least twice a day to mix the salt)
↓
Mixing spices
↓
Storage at ambient temperature
(In cool dry place)
Flow chart of mango pickle
Preservation with Vinegar

101
This technology is based on the addition of food grade vinegar which has a bacteriostatic
action in concentrations up to 4% acetic acid and bactericidal action in higher concentrations.
Vegetables preserved in vinegar need to reach a final concentration of 2-3% acetic acid in order to
assure their preservation.
To achieve this final concentration, 6-9% acetic acid vinegar is used, as related to the specific ratio
of vinegar: vegetable. This higher concentration treatment helps to expel the gases present in the
intercellular spaces of vegetable tissue.
In vinegar pickles, salt (2-3%) and sometimes sugar (2-5%) are also added. If the vinegar
concentration is lower than 2%, vinegar pickles need to be submitted to pasteurization in order to
assure their preservation. Mango, garlic, chilies, etc. are preserved as such in vinegar. Vinegar
pickles are the most important pickles consumed in other countries.
Onion (small)
↓
Peeling
↓
Blanching for 5 minutes
↓
Filling blanched onions in jar
↓
Addition of salt
↓
Keeping for 1-2 days
↓
Draining off water
↓
Addition of vinegar and Spices
↓
Storage
Flow chart of onion pickle

101
Preservation with Oil
Oil pickles are highly popular in India. They are highly spiced. In India, mustard oil, rapeseed oil,
sesame oil are generally used. The fruits or vegetables should be completely immersed in the edible
oil. Cauliflower, lime, mango and turnip pickles are the most important oil pickles. The pickle
remains in good condition for one to two years if handled properly. A schematic flow chart of lemon
pickle by using oil as preservative is shown in
Lemon
↓
Washing
↓
Cutting into 4 pieces
↓
Squeezing out juice from 1/4th amount of fruit
↓
Mixing spices and salt with juice
↓
Mixing with pieces
↓
Filling in jar
↓
Keeping in sun for 4-6 days
↓
Addition of oil after heating
↓
Cooling it
↓
Storage
Flow chart of lemon pickle

101
Preservation with Salt, Vinegar, Oil and Spices
This method combines the advantages of fermentation action of salt and the preservation action of
both vinegar and oil. The flavouring property of spices is also made use of. The spices are usually
fried in oil and mixed to the prepared fruit/ vegetable before the addition of vinegar. The spices can
be added separately or in the form of spice vinegar. A schematic flow chart of tomato pickle by using
salt, vinegar, oil and spices as preservative is shown
Tomatoes
↓
Washing
↓
Blanching for 5 minutes
↓
Cooling immediately in water
↓
Peeling & Cutting into 4-6pieces
↓
Frying all ingredients in a little oil (except vinegar)
↓
Mixing with pieces
↓
Heating for 2 minutes & Cooling
↓
Addition of vinegar & remaining oil
↓
Filling in jars & storage
Flow chart of tomato pickle

101
Problems in pickle making
 Bitter taste: Use of strong vinegar or excess spice or prolonged cooking of spices imparts a
bitter taste to the pickle.
 Dull and faded product: This is due to use of inferior quality materials or insufficient curing.
 Shriveling: It occurs when vegetables (e.g., cucumber) are placed directly in a very strong
solution of salt or sugar or vinegar. Hence, a dilute solution should be used initially and its
strength gradually increased.
 Scum formation: When vegetables are cured in brine, a white scum always forms on the
surface due to the growth of wild yeast. This delays the formation of lactic acid and also helps
the growth of putrefactive bacteria which cause softness and slipperiness. Hence, it is
advisable to remove scum as soon as it is formed. Addition of one per cent acetic acid helps to
prevent the growth of wild yeast in brine, without affecting lactic acid formation.
 Softness and slipperiness: This very common problem is due to inadequate covering with
brine or the use of weak brine: The problem can be solved by using a brine of proper strength
and keeping the pickles well below the surface of the brine.
 Cloudiness: When the structure of the vegetable used in pickling, e.g., onion, is such that the
acetic acid (vinegar) cannot penetrate deep enough into its tissues to inhibit the activity of
bacteria and other microorganisms present in them, fermentation starts from inside the tissues;
rendering the vinegar cloudy. This microbial activity can only be checked by proper brining.
Cloudiness may also be caused by use of inferior quality vinegar or chemical reaction between
vinegar and minerals.
 Blackening: It is due to the iron in the brine or in the process equipment reacting with the
ingredients used in pickling. Certain microorganisms also cause blackening.
Chutneys-
Good quality chutney should be palatable and appetizing. Mango chutney is an important food
product exported from India to many countries. Apple and apricot chutneys are also very popular in
the country. The method of preparation of chutney is similar to that for jam except that spices,
vinegar and salt are added.
Preparation of Chutney
Ripe fruit or vegetable is selected, cut into slices or pieces of suitable size and are softened by
boiling in water. These are then, slowly cooked at a temperature below boiling point. Onion and
garlic are added at the start to mellow their strong flavours. Spices are coarsely powdered before they
are added to the product. Whole spices, if used, are bruised and tide loosely in muslin cloth before
adding to the mixture and removed before bottling. Vinegar, sugar, and spices are added just a little
before the final stage of boiling. This prevents the loss of some essential oils of spices and vinegar

101
due to volatilization. Long cooking of sugar darkens the colour of the chutney. For the preparation of
dark colour chutney brown sugar is usually preferred, where as, white sugar is preferred for white
colour chutneys. Spiced vinegar gives high quality product. Chutneys usually get thickened on
cooling. The chutneys are bottled, while hot, in clean and warm jars which are then, adequately
sealed and sterilized.
Fruit/Vegetable
↓
Grading for Ripeness & Freshness
↓
Washing
↓
Peeling, Slicing/Crown Removing/Coring
↓
Boiling
↓
Cooking with Onion and Garlic and/or Ginger
↓
Adding Coarsely Powdered Spices/ Spiced Vinegar & vinegar
↓
Coking till required consistency obtained
↓
Boiling hot and sealing
↓
Sterilizing
↓
Cooling
↓
Labeling & Storage
Flow chart of chutney production

101
Chutney and its Method of Preparation
 The method of preparation of chutney is similar to that for jam except that spices, vinegar and
salt are added.
 The fruits/vegetables are peeled, sliced or grated, or cut into small pieces and cooked in water
until they become sufficiently soft.
 The quality of chutney depends to a large extent on its cooking which should be done for a
long time at a temperature below the boiling point.
 To ensure proper thickening, cooking is done without a lid even though this results in some
loss of volatile oils from the spices.
 Chopped onion and garlic are added at the start to mellow their strong flavours. Spices are
coarsely powdered before adding.
 Vinegar extract of spices may be used instead of whole spices. Spice and vinegar are added
just before the final stage of cooking, because prolonged boiling causes loss of some of the
essential oils of spices and of vinegar by volatilization. In mango and apricot sweet chutneys,
where vinegar is used in large quantity, the amount of sugar added may be reduced because
vinegar itself acts as a preservative.
 The chutneys are cooked to the consistency of jam to avoid fermentation.
Some of the common recipes for preparation of chutney are given below
Sweet mango chutney
Mango slices or shreds 1 kg, sugar 1 kg, salt to taste, onions (chopped) 50g, garlic (chopped) 15g,
ginger (chopped) 15g, red chilli powder 10g, black pepper, cardamom (large), cinnamon, cumin,
aniseed (powdered) 10g each, clove (headless) 5 numbers and vinegar 170 ml.

101
Apple chutney
Apple slices 1 kg, sugar 750 g, dried dates (chopped) 100g, salt to taste, raisins 50g, ginger
(chopped) 15g, red chilli powder 10g, black pepper, cardamom (large), cinnamon, cumin, aniseed
(powdered) 10g each, clove (headless) 5 numbers, onions (chopped) 250g, garlic (chopped) 15g, and
vinegar 200 ml.

101
Tomato Chutney
Tomato chutney is produced from tomato pulp, and other ingredients like sugar, salt, vinegar, spices,
onion, ginger, garlic, etc. The preparation of tomato chutney is similar to that of the chutney
produced from other fruits and vegetables.
QUALITY STANDARDS
FPO specifications for the
products discussed in the
present unit. FPO
specifications for tomato
products, pickles, chutneys
and sauces are as follows:

101
Some important considerations:
 In case of oil pickles the name of the fruit or vegetable used shall be declared on the label.
 When more than one vegetable is used in vinegar pickle the product shall be labeled as ‘mixed
pickles’.
 In case of sauces other than tomato and soybean, the names of fruits, vegetables or dried fruits
used shall be declared on the label.
 In case of fruit chutney, the names of fruits may not be declared on the label, However, in
case of mango chutney or other chutneys the content shall be declared on the label.
 Permissible limit of Copper (a toxic element) in tomato ketchup is 50 ppm, whereas the same
can be up to 100 ppm in tomato puree, paste, juice powder and cocktails.
KEY WORDS
Brine: Solution of common salt.
Brining: Steeping of the vegetables in a salt solution of pre determined concentration for a certain
length of time.
Vinegar: It is a liquid obtained by alcoholic and acetic fermentation of material containing sugar. It
contains about 4% acetic acid.
Chutney: It is an unstrained, concentrated product, which contains a mixture of fruit or vegetable,
spices, salt and/ or sugar, vinegar.
Sauce: It is a strained, concentrated product, which contains a mixture of fruit or vegetable, spices,
salt and/ or sugar, vinegar. These are thinner and smoother in consistency than chutneys.
Tomato paste: It is a concentrated and strained tomato product and contains not less than 25%
tomato solids.

101
Tomato puree: It is a concentrated and strained tomato product but thinner than the paste and
containing not less than 9.0 % of salt free tomato solids.
Spice bag: Bruised spices tide loosely in muslin cloth
Ketchup: Thick sauces made from tomato

101
Tomato Products -Ingredients and their role, process for the manufacture of tomato
ketchup, sauce, puree and paste
Tomato is grown in our country in abundance, in all seasons. The farmer will get a very low profit
during the peak-harvesting season and nearly 25% of the produce is spoiled due to improper post
harvest practices. Such losses can be avoided by converting tomatoes into delicious products. Tomato
can be processed to a variety of products like; canned tomato, paste, puree, juice, ketchup and sauce.
In India tomato sauce and ketchup are very popular and are being manufactured on an increasingly
large scale.
Tomato ketchup: – Tomato ketchup (catsup, catchup) can be defined that it is a clean, sound product
made from strained tomato juice, with spices, sugar, salt, vinegar, onion and garlic etc.
Ketchup is a condiment, usually made from tomatoes. It should contain not less than 12 percent
tomato solids and 28 percent total solids. Ketchup with a 28-30% TSS has a better flavour. Tomato
ketchup is similar to tomato sauce except that it is thick in consistency.
Raw Materials
The main ingredients of ketchup are tomatoes, sweeteners, vinegar, salt, spices, flavorings, onion,
and/or garlic.
 The types of sweetener used are usually granulated cane sugar or beet sugar. Other
sweeteners include dextrose or liquid sugar in the form of corn or glucose syrup. About one
third of the sugar required is added at the time of commencement of boiling to intensify and
fix the red tomato colour. If the whole quantity of sugar is added initially, the cooking time
will be longer and the quality of pulp will be adversely affected. Generally the sugar content
in sauces/ ketchups varies from 10- 26 %.
 Good quality vinegar is essential for the preparation of high quality sauce/ketchup. Vinegar
helps to preserve the ketchup. It should contain 5.0-5.5% acetic acid and should be added
when the product has thickened sufficiently, so that the acid is not lost by volatilization.
Tomato sauce/ ketchup generally contain 1.25-1.5% acetic acid. Sometimes glacial acetic acid
(100% acetic acid) is used which is colorless and cheaper than vinegar.
 Salt is used as a main flavouring ingredient in ketchup but slat also bleaches the colour of the
tomato product. It is therefore desirable to add towards the end of cooking process.
 The spices commonly used to enhance the flavor of the tomatoes are all spice, cassia,
cinnamon, cayenne, cloves, pepper, ginger, mustard, and paprika. Pepper is widely used as a
condiment, preferred for its characteristic aroma, pungency and biting taste. It is used to
garnish culinary preparations, ketchups, sauces
Thicker consistencies require a greater ratio of sugar and spices relative to the tomato juice.

101
The Manufacturing Process
1. Selection of Tomatoes: - Tomato which are superior in color, flavor, texture, and yield.
Consistency is an important factor, as slight variations in tomato characteristics could alter the
flavor and color of the finished product.
2. Pre-washing and washing: Pre-washing is carried out by immersion in water, cold or heated
up to 50°C (possibly with detergents to eliminate traces of pesticides). Then washing is
performed with water sprays.
3. Sorting: Only sound ripe red coloured tomatoes are used for the juice preparation. This is
done on rolling sorting tables. This enables the removal of non-standard tomatoes − with
green parts, yellow coloured, etc.
4. The tomatoes are cut and chopped.
5. Now chopped tomatoes are precooked at 70 to 900 C in stainless steel vats to preserves the
tomatoes and destroy bacteria.
6. Crushing and pulping: Crushing is carried out in special equipment. Fluted wooden roller
crushers are utilized for this purpose. The crushed tomatoes can be pulped by the hot process
or by the cold process.
a) In hot pulping, crushed tomatoes are boiled in their own juice in steam jacketed stainless
steel pans or in aluminum pans for 3 to 5 minutes. Heat treatment yield higher juice
recovery than cold method. Because heat treatment inactivates/destroy the pectate enzymes
due to this pectin present in the skin and seeds separate into liquid and pulp easily. This
process also contributes to the maintaining of vitamins and natural pigments.
b) In cold pulping, the tomatoes are crushed in cold and as such passed through a pulper.
Here the extraction of juice is difficult and yield will be less compared to hot process.
7. Extraction: Extraction of juice and part of pulp (maximum 80%) is performed in special
equipment / tomato extractors with the care to avoid excessive air incorporation. In some
installations, as an additional special care, a part of pulp is removed with continuous
centrifugal separators.
8. Adding ingredients and cooking: - The pulp is pumped into cooking tanks or kettles and
heated to boiling. Foaming may occur if fresh tomato pulp is used, but can be corrected with
anti-foaming compounds or compressed air.
Precise amounts of sweeteners, vinegar, salt, spices, and flavorings are added to the
tomato pulp. Most spices are added early in the cooking process. To avoid excessive
evaporation, volatile spice oils and vinegar must be mixed in later. Onions and garlic can be
mixed in with the spices, placed in a separate bag, or chopped and added to the pulp.

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