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1. Food Analysis
Lecture 1

2. Introduction
Food products are analyzed for a variety of
reasons, e.g.,
 Compliance with legal and labeling
requirements,
 Assessment of product quality,
 Determination of nutritive value,
 Detection of adulteration,
 Research and development.
Mengapa produk makanan perlu
dianalisis., beri 5 alasan.

3.  Food is a mixture of chemicals.
 Usually, food components are
distinguished in four categories:
nutrients, toxins of natural origin,
contaminants, and additives.
 The nutritients account for more than
99.9% of the food.
 The main classes of nutrients are
carbohydrates, proteins, fats, vitamins,
and minerals, and all of them may pose
toxicological risks to the consumer.

4.  Most of the food is treated in some
way to improve its shelf
life, texture, palatability or
appearance.
 So, it is important to know what
happens to the various food
components on the way from raw
material to consumer.
 The food industry is a
large, continuously expanding

5.  Although there are people who would
like to do without industrially
processed food and go back to
nature, this is not possible on a large
scale from a socio-economical point of
view.
 The majority of the population depend
on the food manufacturing industry for
their daily food supply.

6. From raw materials to
consumer
 Food processing can be regarded as
the conversion of raw agricultural
material into a form suitable for eating.
 The first step is collecting or
harvesting the raw material. This is
primarily carried out by the producer.
 The second step is often separating
the actual foodstuff from the bulky and
indigestible material.

7.  In the third step from raw materials to
consumer, the raw materials and
purified components are converted to
palatable food products.

8. Natural toxins
 A number of toxic components of natural
origin have been identified, and the
mechanisms underlying their toxicities
elucidated.
 For example, the potato contains more
than 250 substances including
solanine, which is known to cause
neurotoxic effects in animals and man.
 Usually, natural toxins are not acutely
toxic, except in a few cases in animals.

9.  An example is tetrodotoxin, a neurotoxin
first identified in puffer fish, a Japanese
delicacy.
 Expert cleaning of the fish prevents
transmission of the toxin to the edible
parts of the fish.
 Yet, accidents happen each year.
 Most of the natural toxins, particularly
those occurring in plant-derived foods,
induce adverse effects only after
chronic ingestion or by allergic
reactions.

10.  Many minor plant food components
have not been chemically identified yet
and, consequently, have not been
evaluated for any toxic properties.
 Indications of their presence have been
obtained from chromatographic and
spectroscopic studies.
 It may even be expected that with the
further development of analytical
techniques still more components will
be found, and of these more may
appear to be toxic.

11. Endogenous toxins of plant
origin
 There is no simple way of classifying
toxic food components of plant
origin, since this category comprises
many different types of substances.
 These are classified on the basis of:
◦ Common functional groups
◦ Physiological action
◦ Type of effect

12. Antinutritives
 Food components can also cause
toxic effects without being the active
agents themselves.
 The substances in question are known
as antinutritives.
 They induce their toxic effects
indirectly, by causing nutritional
deficiencies or by interference with the
functioning and utilization of nutrients.

13.  Antinutritives can interfere with food
components before intake, during
digestion in the gastrointestinal
tract, and after absorption in the body.
 The adverse effects of antinutritives
usually do not manifest themselves as
readily as those of the directly acting
toxic food components.
 The conditions under which
antinutritives may have important
implications are malnutrition or a
marginal nutritional state.

14. Contaminants
 Food contaminants are substances that
are included unintentionally in foods.
 Some are harmless and others are
hazardous because of the toxicological
risks from their intake to the consumer.
 Harmless contaminants may still have
the disadvantage of interfering with food
processing and causing interactions
during storage.
 Examples are metal ions and plant
pigments.

15.  Contamination can occur at every step
on the way from raw material to
consumer.
 Raw material of plant origin can be
contaminated with environmental
pollutants, such as heavy
metals, pesticide residues, industrial
chemicals, and products from fossil
fuels (in the exhaust gases of
combustion engines).

16.  The sources of contaminants in raw
materials of animal origin — mainly
fish and milk — are to a large extent
comparable to those of raw materials
originating from plants.
 In animal products also, residues of
veterinary drugs and growth promoting
substances may be present.

17.  During processing, food can be
contaminated with processing
aids, such as filtering and cleaning
agents, and with metals coming from
the equipment.
 Finally, contaminants can be included
in foods during packaging and
storage.
 These can originate from
plastics, coatings, and tins.

18. Food additives
 Food additives are those substances
that are intentionally added to food for
maintaining or improving its
appearance, texture, flavor, and
nutritional value, as well as for the
prevention of microbial spoilage.

19.  This includes any substance intended
for use in
manufacturing, processing, preparing,
packaging, transporting, or keeping
food.
 Evaluation of the safety of the
intended use of additives in food is
extensively provided for by regulation
and legislation.

20. Five main categories of additives
are distinguished:
 Texturizing agents: gelling agents,
thickeners and emulsifiers;
 colorings;
 Flavoring agents: flavors, flavor
enhancers and non-nutritive sweeteners;
 Preservatives: antioxidants and
antimicrobials;
 Miscellaneous additives, such as
anticaking agents, catalysts, clarifying
agents, filter aids, and solvents.