this presentation is in two sections, 1st one is about protein quality estimation and 2nd is about novel protein sources. hope it would be helpful for u guys...

1. A
SEMINAR
ON
PROTEIN QUALITY
and
NOVEL PROTEIN SOURCES
Presented to: Presented By:
Dr. Vibha Bhatnagar Swati Shukla
Dept. of Food and Nutrition Ph.D.
College of Home Science Food & Nutrition

2. Proteins
We are the basis of the
structure and function of life;
composed of twenty amino
acids, the blocks; organized
into primary secondary
tertiary quaternary
structure; classified as
simple, conjugated and
derived proteins
( it speaks…..)

3. Am
I
n
o
A
c
I
d
s

4. Functions of Protein

5. Protein Quality
The nutritive value of the protein
depends to an important degree on
the relation of its amino acids in its
molecule to those required for
building of new tissues. If the amino
acids composition of a substance
meets the amino acid composition
of a tissue, the food protein is of
high quality

6. Methods of Assessing
Protein Quality

7. Digestibility of Protein

8. Protein’s Digestibility
D
E
P
E
N
D
S
O
N
Food ingested
Enzymes involved
Anti-nutrients

9. Nitrogen Factor
Protein = 16 % Nitrogen and for converting Nitrogen content to
protein; formula is :
(PG = NG x 100 = NG x 6.25 )
16
Where PG= grams of protein in 100 g of food and NG = grams
of nitrogen in 100 g of food.
NOTE: This conversion factor is an average factor, conversion factors
for each category are available

10. Methods for assessing
Protein Quality
Rationale of Scoring procedure
Assays Utilizing the Amino Acid Profile Alone
or in Combination with Protein Digestibility
Microbial Assays

11. Rationale of Scoring Procedure
 In 1946 Block and Mitchell introduced the concept of
assessing the nutritional quality of a protein on the basis
of its constituent amino acids and the value obtained was
called chemical score.
 The method consists of calculating, by the use of tables
or from direct analysis, the quantity of each essential
amino acid contained in a protein or mixture of proteins.

12.  The values are expressed individually in proportion to the content of a
corresponding amino acid in a suitable reference protein or amino acid
pattern.
 The amino acid that shows the lowest proportion is called the limiting
amino acid, and the ratio obtained is the score.
 The score for an individual protein food is defined as:
(mg of amino acid per g of test protein)
(mg of amino acid per g protein in reference pattern)
(mg of amino acid per g N in test protein)
(mg of amino acid per g N in reference pattern)

13.  In the 1973 FAO/WHO report on Energy and Protein
Requirements, the scoring pattern for determination of
amino acid score was based on more recent evaluations of
human amino acid requirements.
 The new scoring pattern was considered preferable to the
use of whole egg or milk protein as the optimal pattern
 Although there was no experimental evidence that the
provisional patterns based on what are now known as minimal
requirements were superior to the "patterns found in good
foods such as those of milk and egg.“

14. Assays Utilizing the Amino Acid Profile Alone or
in Combination with Protein Digestibility
These assays were further developed to
improve the accuracy of protein scoring
procedures, so that chemically
determined amino acid content may be
corrected for biological availability by
use of digestibility factors.

15. These are discussed as :
Biological assay
Biological value
Net Protein Utilization
Protein Efficiency Ratio
Net Dietary protein Energy Ratio
Net Protein Ratio

16. Biological assay (dietary coefficient)
The term digestibility coefficient of protein refers to the
percentage of the ingested protein absorbed into the blood
stream after the process of digestion is complete.
D.C. = N Intake-(N in faeces - endogenous faecal N)
Nitrogen intake
= I – (F –Fm)
I
100 x
Where F – Fm is the food nitrogen lost in digestion

17. Biological Value
 The biological value of given protein depends not only on
amino acid content, but also on the needs of the consumer.
 For example: growth carries with it a demands for specific
or particular amino acid as a part of total nitrogen
requirements, whereas maintenance ( as in the adult) has a
total nitrogen requirement with less straight demands for
specific amino acid.
 But using a holistic approach for assessing protein quality two
terms i.e. ‘Endogenous and Exogenous’ Nitrogen as given by
Folin were devised by H.H. Mitchell in 1924.

18.  Hence lastly B.V. was considered as a ratio of the nitrogen
retained to that absorbed multiplied by 100.
 They are very useful in the context of evaluating the
biological usefulness of dietary protein.
N retained
N absorbed
B.V.= 100 x

19. Where,
N1 (NFT-NFF)-(NUT-NUF)
N1-(NFT-NFF)
B.V.= 100 x
B.V.= biological value
N1= Nitrogen intake
NFT= fecal nitrogen during test period
NFF= fecal nitrogen during test period- free period
NUT=Urinary nitrogen during test period
NUF=Urinary nitrogen during test period- free period

20. 1st group= non-protein diet
(10 days)
Two groups of albino rats
(28 days old)
2nd group= 10% protein containing
diet (for 10 days)
Fed
on
 The protein to be tested is fed to the animals as the sole source of
nitrogen in the diet and below the level needed for maintenance.
 The diet, urine, feces were analysed for testing.

21. Net Protein Utilisation
 In 1955 ‘ miller and bender develop more accurate method for
the evaluation of protein quality which actually measures the
retention of nitrogen in carcass, from the ingested protein
nitrogen.
 It is also known as NPU and can be calculated as:
(Body nitrogen of the test group) – ( body nitrogen of the non protein group)
+ nitrogen consumed by non protein group
Nitrogen consumed by test group

22. Where,
Bf - Bk + IK
If
X 100
NPU =
Bf= nitrogen of animals fed test protein diet
BK= nitrogen of animals fed nitrogen free diet
IK= absorbed nitrogen of animals fed nitrogen free diet
IF= absorbed nitrogen of animals fed test protein diet

23. 1st group= non-protein diet
(10 days)
Two groups of albino rats
(28 days old)
2nd group= 10% protein containing
diet (for 10 days)
Fed
on
 The animals were killed on the end of 10 days.
 Body nitrogen is estimated by Kjeldahl method.

24. Protein Efficiency Ratio
 The PER method was developed by Osborne Mendel and Ferry
in 1919 .
 It is based on the growth of young rats.
 Therefore it is defined as weight gain per gram of protein
intake.
Gain in weight (g)
Protein intake (g)
PER =
 Group of albino rats were fed for period of 4 weeks on
different protein diets at 10% protein.
 Records gain in body weight and protein intake were analysed.

25. Net dietary protein Energy ratio
 This method is the modification of PER method.
 Develop to express the protein content of food in terms of
percentage of energy provided by the protein.
Protein energy
Net Dietary Intake
Net Dietary Protein Energy Ratio =
 This method accounts for the maintenance need of the
animals .
 In this method two groups of animals are used.
 One is fed on N-free diet and other on test diet.
 All the pitfalls of using N-free diet are accompanied.

26. Net protein Ratio
 This method of assay was introduced by Bender and Doell in
1957.
 This methods is the modification of PER method.
 an allowance is made for the protein requirements and also for
maintenance.
Gain in wt(g) of the test group +loss in wt(g) of non-protein group
Protein intake (g) of test group
NPR =

27. Two groups of weaning albino
rats
1st group= experimental group 2nd group= control group
diet containing 10% of the
test protein
Non-protein diet
For the period of 10 days
 The NPR is calculated by adding the loss in weight of the test
group and dividing the total weight(g) quantity of protein
consumed by the test group.

28. Microbial Assays
These methods were first used to assay amino acids after acid
hydrolysis of the protein, but they have also been used for
determination of available amino acids and for assay of
protein quality.
The most common used microbes for assessing protein quality are:
a) Streptococcus zymogenes
b) Tetrabymena pyriformis

29. a) Ford in (1962) developed a method using
‘Streptococcus zymogenes’ to measure available:
 Unfortunately, the organism does not require lysine; thus,
neither total nor available lysine could be determined.
 The organism can hydrolyse protein by its own enzymes,
but the process is relatively slow.
 But, the assay can be improved if the protein is
subjected to preliminary treatment with papain.

30. b) Another organism that is currently being used is
‘Tetrabymena pyriformis’, a ciliated protozoan.
 It was first used by the Fernell and Rosen(1956) also
known as Tetrabymena Assay.
 it can ingest particles of food, thereby not having to
rely entirely on soluble nutrients for growth.
 Furthermore, it requires the same ten essential amino
acids as required by the growing rat (i.e., including
lysine), and thus shows an advantage over S. zymogenes.

31.  As an index of growth, the organisms are counted and
compared with those achieved with a protein or amino
acid standard
 It was demonstrated that Tetrabymena growth using
a Coulter counter, was highly correlated to PER values
obtained with rats for selected foods.

32. Advantages
Speed, simplicity and cost effective
 Because animal and clinical facilities are not used
 the procedure for scoring proteins and diets from amino acid
data can be by far the simplest, fastest, and least expensive
of all methods for determination of protein quality.
 The technique can range from the extremely simple, where
literature data for amino acids and digestibility are used, to
the more complex, where these data are obtained by direct
analyses using chemical or microbiological techniques, as have
been described earlier.

33. Identification of the limiting amino acid
 The limiting amino acid for a protein or a diet can readily be
identified by the use of scoring procedures.
 With any animal assay, several trials are necessary wherein
the protein is supplemented with various amino acids before
the actual limiting amino acid can be identified.
 For the identification of the limiting amino acid by an amino
acid score, the 1973 FAD/WHO pattern has been shown to be
superior to several previous patterns.

34. Estimation of complementary value
 Once the amino acid composition of a protein is
established, the complementary effect of that protein in
combination with other proteins in the diet can be
evaluated.
 This technique, together with simple computer
programmes, can be used to develop complementary protein
mixtures of maximum quality and/or maximum utilizable
protein at minimum cost .
 The best mixtures obtained in this way would then be
subjected to biological or clinical evaluation.

35. Drawbacks
Amino acid availability
 As chemical analysis of amino acids is carried out after acid
hydrolysis of the protein, the analysis yields total amino acid
content.
 Some of the amino acids may, however, have been biologically
unavailable. This lowered availability may or may not be
reflected by impaired digestibility.
 The related degree of error varies with the food, but may be
considerable in proteins and processed foods that have been
heated.

36.  For other protein foods that have been extensively processed-for
example, by dehydration-amino acid availability studies are
essential; in these circumstances, scoring without considering
availability data is unrealistic.

37. Amino acid release during digestion
 It has been shown that amino acids are released at different
rates during digestion of proteins and that the protein of the
intestinal contents may originate predominantly from digestive
secretions and sloughed mucosal cells rather than from
dietary protein.
 The rate of digestion may affect protein nutritional value and
there is within the gastrointestinal tract a large pool of labile
protein that plays a part in overall protein metabolism.
 However, how greatly these factors affect nutritive value is
still unclear.

38. Possible different utilization of amino acids and proteins
 Amino acid mixtures or amino acid-supplemented protein
foods may not be utilized as efficiently as proteins of the
same amino acid composition.
 Rose and his associates found that more dietary energy was
needed to maintain nitrogen balance with amino acid mixtures
than with whole protein of the same composition.
 It is postulated that the amino acid mixtures may have been
absorbed more rapidly than the amino acids derived from
protein, and that the rate of supply of energy may not have
been adequate for efficient utilization of the amino acid
mixture.

39.  In practice, however, the protein value of diets fortified
with small quantities of amino acids agrees well with
expectations, indicating that this effect is probably not of
great importance in practical dietary evaluation.

40. Non-agreement for very poor-quality proteins
 Although there is a good correlation between amino acid
score and biological assay for proteins with a BV greater than
about 0.40, the relationship varies with the limiting amino
acid below this level.
 Proteins completely lacking lysine can still have a BV equal to
0.40, and proteins lacking other amino acids can have values
significantly above zero.
 The relationship changes below the value of 0.40 due to
differing needs for maintenance and growth and the capacity
of organisms to adapt to low intakes of lysine.

41. Role of non-specific nitrogen
 Non-specific nitrogen has been defined by ‘Kies’ as nitrogen
that is metabolically available and that can lead to minimal
toxicity in the quantities used.
 It may include nitrogen furnished by the non-essential amino
acids or excess essential amino acids, or by non-protein
sources such as urea or diammonium citrate.
 In most cases, the extra nitrogen would be accounted for as
part of the total nitrogen and the score would be reduced.
 Non-specific nitrogen can affect apparent requirements for
both protein and specific amino acids.

42. Role of toxic materials
 Because amino acid scoring examines only the level of amino
acids in relation to total nitrogen, the presence of toxic
materials in the food, could, if active at the level fed, affect
the relationship between score and BV.
 In this context, the term "toxic" is used in its broadest sense
as any adverse physiological response that detracts from the
nutritive value of a particular foodstuff.
 Toxic materials in a food would be either foreign chemicals
accidentally present or natural components.
 A large discrepancy between score and BV suggests the
presence of either toxic materials or non-available amino
acids.

43. Conclusion
 The concept of a single pattern of amino acids that may be
used as a yardstick in comparing the nutritive value of food
and diets is subject to the same limitations and qualifications
as is the concept of "protein quality."
 The relative proportions in which the essential amino acids are
needed almost certainly depend upon the species, its
physiological state, and interrelationships and interactions
among the amino acids themselves.

44.  The pattern of amino acids required for maintenance may
be quite different from the optimal pattern to support
maximum growth.
 In addition, the limited accuracy of amino determinations in
food and the problem of biological availability of the amino
acids present further complications.
 However, the advantage of a method of dietary assessment
in terms of amino acids is considerable, and is, in many
circumstances, the only practical approach.

45. Novel Protein Sources

46. Introduction
Change is nothing new when it comes to foods.
Just as more than 45 years ago ‘Louis Pasteur’
found a way to kill bacteria in beer by applying
heat. So modern technology keeps coming up with
innovative processes for the preparation of the
foods that we eat.

47. Why Novel foods?
International travel
Globalization
Changing Tastes
Increasing Desire to taste new food instead of
traditional one
Advances in genetics traits
Innovation in field of plant breeding
Rapid increasing population
Increasing demands of food resources
Problem of under-nutrition

48. What are Novel foods?
Novel Foods ,can be defined as:
“Type of food that does not have a significant
history of consumption or it is produced by a
method that has not previously been used for
food.”

49. What are novel protein sources?
It means protein derived from ‘new sources.
Novel protein are either isolated directly from plants, or
obtained by microbial methods such as from fungi or yeast.
Examples: Mushrooms
spirulina
yeast protein
by-products of oil seeds
food analogues
soy products etc

50. Mushroom
It is fungal fruiting body which produces disseminates spores.
Variables shapes-sizes and verities are there.
In India white bottom mushroom is acceptable.
Popular for their delicacy and flavour rather than food value.
They are excellent source of protein as well as vitamins and
minerals also.

51. Cultivation of Mushroom
 Cultivation of mushroom is done indoors.
 They can be grown on substrate or compost based on various
agricultural wastes which in turn are recycled.
 Availability of raw materials in the area and good local
market should be taken into consideration for it’s farm
establishment.

52. Processing of Mushroom
Canning
Dehydration
Freeze drying
freezing
Steeping preservation

53. Protein Content of Mushroom
Most mushrooms have a high protein content, usually around
20-30% by dry weight.
This can be useful for vegetarians or anyone looking to
increase the protein content in their diet.
Per 100 gram mushroom consists of approximately 1.8gm.
Protein.
Above value is more than any other vegetable.

54. Leaf Protein Concentrates
Leaf protein concentrate (LPC) is a concentrated form of
the proteins found in the leaves of plants.
It has been examined as a human or animal food source,
because it is potentially the cheapest, most abundant source of
available protein
The annual yield of leaf protein can be 2 tones/hac. in Britain
and 3 tones in India.

55. Processing/ Isolation of Leaf Protein
Fresh leaves
disintegration
Filtration
Precipitation
filtration
fibre
Canning of wet cake
washing Water soluble
Drying (dried protein concentrate)

56. Protein Content of LPC
 Carefully made dry leaf protein contains 60 to 65% true
protein. Leaf protein isolates consists of 10 to 20 % protein
on dry basis.
 LPC shows considerable differences in their protein
contents, which may range from 13.7 to 88%.
 Leaf protein is a good source of amino-acids,
with methionine being a limiting factor.

57. Single Cell Protein or Protein from
Petroleum Yeast
Micro-organism have high protein content.
Their rate of growth is very rapid .
Protein synthesis rate in micro- organisms have been found very
favorable as compared to that of animals.
They are economic too as they can be grown on industrial
wastes like spent grains, rot vegetables, fruit baggasses of sugar
cane, molasses, unwanted meat, poultry waste and fish.

58. Today food processing industries are using these in field of bio
technology.
The main production center are United kingdom and France.
Commonly used microbes for this purpose are candid yeast,
aspergillus niger, sacchomyces, fusarium, pseudomonas etc.
The process of fermentation is mainly adopted for producing
protein and yeast cell help in producing it.

59. Protein from Petroleum Yeast
Now a days many types of yeast cell are now used to produce
a high quality protein, these increase the protein content by
50-60% and the bioavailability also.
500 kg yeast grown in suitable conditions can produce 50
tones protein in 1 day.
Their nutritional value includes lysine rich protein which is
very useful when it is combined with cereal diet which is
deficient in lysine.

60. Protein content of some micro-organisms
is-
S. No. Microbes
Amt. of
protein/100gm
1. Sacchomyces 50 g
2. Candida 70g.
3. Fussarium 60g.
4. Pseudomonas 80g.

61. Spirulina
Also known as Blue green algae
Nutrient dense food material in nature, used for health food
and for some therapeutic uses.
It is spiral cylindrical filaments with length of about 300 to
500um with width of spirals 6-8mm.
World wide 1200 tones spirulina is produced.
Major centers are Japan, united states, Vietnam, Taiwan and
Thailand.

62. Cultivation of Spirulina
The cultivation of spirulina involves 3 well
defined steps:
Cultivation/production
Harvesting
drying

63. Clean water
Spirulina
drying
 Inoculum
 Nutrients &
bicarbonates
 Sunlight
 Agitation
 pH (8-9)
Processing of Spirulina
Harvesting of biomass
Algal powder
 Specialized feeds
 Food Supplements
 Therapeutic Uses
 Biochemical
production
Other uses:
 Sericulture
 Bio-energy

64. Protein content of Spirulina
 The protein efficiency ratio of spirulina has been reported to be
higher than vegetables, cereals and soy proteins.
 Dried Spirulina contains about 60% (51–71%) protein.
 It has complete protein containing all essential amino acids, though
with reduced amounts of methionine, cysteine and lysine when
compared to the proteins of meat, eggs and milk.
 It is, however, superior to typical plant protein, such as that from
legumes.
 The U.S. National Library of Medicine stated that spirulina was no
better than milk or meat as a protein source, and was approximately
30 times more expensive per gram.

65. Spirulina (dried)
amino acid value per 100 g
Protein 57.47 g
Threonine 2.97 g
Isoleucine 3.209 g
Leucine 4.947 g
Lysine 3.025 g
Methionine 1.149 g
Cystine 0.662 g
Phenylalanine 2.777 g
Tyrosine 2.584 g
Valine 3.512 g
Arginine 4.147 g
Histidine 1.085 g
Alanine 4.515 g

66. Food analogues
Analogues are food product that which is designed as an
alternative to the traditional animal protein foods such as
meat, poultry, seafood or dairy products.”
They are not just merely substitutes for animal protein products
but are an entirely separate class of food.
There are mainly 2 types of analogues:
Meat analogue
Dairy analogues

67. 1.Meat analogues
Meat by analogues were first developed by ‘John Harvey Kellog’
in 1898. Their analogues were based on wheat gluten.
After that in 1955 ‘Hartman and Robert’ blended the proteins
from soy, wheat, yeast and egg albumin.
But in present time there is a great challenge to the food
technologist in the design of these sophisticated food products
is in the areas of taste and texture.
Examples: processed meat such as bologna, salami, precooked
sausages, textured vegetable protein.

68. Textured Vegetable Protein
TVP is the generic name given to a range of different
products from spun fiber to extruded meat analogues.
Texurization involves the conversion of powdered proteins into
cubes, chunks or granules with mouth feel characteristics of
meats.

69. These products are similar to cooked meat and can be frozen,
canned or dehydrated.
Seeds other than soybean used in the preparation of TVP
include sunflower, cotton and groundnut.

70. Artificial Meat analogues
Now there is great innovation is there in this field is the
development of ‘artificial meat’ in the laboratory.
There are number of experiments are going on in this
field and it may be possible in coming future that people
will buy artificial meat from local markets.

71. Dairy Analogues
The most widely known dairy analogue are margarine, whipped
toppings and non dietary coffee whiteners.
These products have world wide success in the world market
from last 30 years.
Now analogues of cheese, ice cream, and other milk based
desserts have also been developed.

72. Protein content of Mararine
Margarine (1 tablespoon) Protein (g)
Margarine, regular 0.13g
Margarine, soft 0.12g
Margarine, butter blend 0.12g
Margarine-like spread,40 percent fat 0.06g
Margarine-like spread, soybean 0.09g
Margarine-like spread, tub 0.09g

73. By-Products of oil seeds
Nuts and oil seeds in general are rich sources of proteins.
Edible oilseeds meals obtained from oilseeds are used in
preparing infant foods and protein foods for feeding infants and
preschool children in developing countries.
Examples: soybean meal, groundnut meal, cotton seed meal,
sesame meal, coconut meal, rapeseed meal etc.

74. Proteins content of By-Products of oil seeds
1-oz. serving of peanuts, the equivalent of about a handful,
provides 7 g of protein and a little more than 2 g of fiber.
Two tbsp. of peanut butter contains 8 g of protein and 2 g of
fiber.
Even though peanuts are not actually in the nut family, they do
contain more protein than any kind of nut, according to the
Peanut Institute.
The high level of protein in peanuts also contributes to
improving satiety so you're less hungry after eating them, which
can help you lose weight.

75. Significance of Peanut Protein
Peanut’s
fibre
Blood
sugar
Bio-activates It converts
Arginine
Nitic Oxide
 Improved blood flow
 Relax the arteries
 Lowers blood pressure
T
o
Eneregy
Results in

76. According to the Institute of Medicine of the National
Academies, the recommended level of daily protein intake for
adults is 0.8 g per kg of body weight, or about 64 g for
someone who weighs 160 lbs. This means that a 2-oz. serving, or
two handfuls, of peanuts provides approximately one-fifth of
your daily protein requirement.

77. Soya-bean meal
Soybean meal is an excellent choice as a supplemental protein
source for a number of reasons including the following:
Soybean meal contains a high level of protein in comparison
to other plant protein sources.
Soybean meal has an excellent profile of essential amino
acids as well as other nutrients also.

78. Protein isolation from oilseeds and nuts
Solvent extraction of edible soybean or peanut meal
Extraction of protein with dilute sodium hydroxide at pH 8
Precipitation of proteins at pH 4.5 from the extract by addition ofHCL
Filtration of protein and washing with water &
Solublizing the wet protein in water by adjusting pH 7.0
and spray drying

80. The 1973 report states:
 Provided that the lowest score obtained for any of the essential
amino acids is used (i.e., the most limiting amino acid) the score
may be taken as a first approximation to the probable efficiency
of utilization of the test protein or mixture by children, and may
permit a rough correction of protein requirements for the quality
of dietary protein.
 This score may under estimate the quality of protein for adults,
who’s essential amino acid needs per gram protein are lower.
Although certain proteins may yield an apparent score above 100,
the value cannot be used to adjust dietary protein requirements
since N intakes would then be less than required to meet N
requirements.(14)

81.  Scrimshaw et al. found that in adult subjects, milk protein could be
diluted 20 to 25 per cent with nonspecific nitrogen before the
protein nutrition, as indicated by nitrogen balance, was adversely
affected.
 The dilution would have reduced the score for milk from 82 to
67;yet, protein needs were still being met.
 It should be emphasized that these data applied to adults and so
the extent to which they are applicable to children needs further
study.
 The role of non-specific nitrogen in the nutrition of humans is still
uncertain.
 Anomalies between score and biological determination of quality can
occur despite the inclusion of added nitrogen as part of total
nitrogen in the calculation of score.(44)

82.  The concept of scoring has been criticized on this basis.
 It has been stated that if mixtures with a score of zero can
have a BV of 0.40, one or the other method is invalid.
 Poor agreement can also occur at low levels of protein.
 In practice, however, very few proteins or actual dietaries
have these very low levels of essential amino acids, and
consequently more are in the range of good agreement
between score and BV.(42)