Index
1.Introduction
2.About Adulterants
3.Aim – 1
4.Aim – 2
5.Aim – 3
6.Results
7.Bibliography
INTRODUCTION
Adulteration in food is normally present in its most crude
form. Prohibited substances are either added or partly or wholly substituted.
Normally the contamination/adulteration in food is done either for financial
gain or due to carelessness and lack in proper hygienic condition of
processing, storing, transportation and marketing. This ultimately results that
the consumer is either cheated or often become victim of diseases. Such types
of adulteration are quite common in developing countries or backward countries.
It is equally important for the consumer to know the common adulterants and
their effect on health.
ABOUT ADULTERANTS
The increasing number of food producers and the outstanding amount of
import foodstuffs enables the producers to mislead and cheat consumers. To
differentiate those who take advantage of legal rules from the ones who commit
food adulteration is very difficult. The consciousness of consumers would be
crucial. Ignorance and unfair market behavior may endanger consumer health and
misleading can lead to poisoning. So we need simple screening, tests for their
detection. In the past few decades, adulteration of food has become one of the
serious problems. Consumption of adulterated food causes serious diseases like
cancer, diarrhoea, asthma, ulcers, etc. Majority of fats, oils and butter are
paraffin wax, castor oil and hydrocarbons. Red chilli powder is mixed with
brick powder and pepper is mixed with dried papaya seeds. These adulterants can
be easily identified by simple chemical tests. Several agencies .have been set
up by the Government of India to remove adulterants from food stuffs. AGMARK –
acronym for agricultural marketing this organization certifies food
products for their quality. Its objective is to promote the Grading and
Standardization of agricultural and allied commodities.
AIM -1
To detect the presence of adulterants in fat, oil and butter.
REQUIREMENTS : Test-tube, acetic
anhydride, conc. H2SO4, acetic acid, conc. HNO3.
PROCEDURE: Common adulterants present
in ghee and oil are paraffin wax, hydrocarbons, dyes and argemone oil. These
are detected as follows :
(i) Adulteration of paraffin wax and hydrocarbon in vegetable
ghee
Heat small amount of vegetable ghee with acetic anhydride. Droplets
of oil floating on the surface of unused acetic anhydride indicates the
presence of wax or hydrocarbons.
(ii) Adulteration of dyes in fat
Heat 1mL of fat with a mixture of. 1mL of concsulphuric acid and 4mL of
acetic acid. Appearance of pink or red colour indicates presence of dye in fat.
(iii) Adulteration of argemone oil in edible oils
To small amount of oil in a test-tube, add few drops of conc. HNO3and
shake. Appearance of red colour in the acid layer indicates presence of
argemone oil.
AIM - 2
To detect the presence of adulterants in sugar
REQUIREMENTS: Test-tubes, dil. HCl.
PROCEDURE: Sugar is usually
contaminated with washing soda and other insoluble substances which are
detected as follows :
(i) Adulteration of various insoluble substances in sugar
Take small amount of sugar in a test-tube and shake it with little water.
Pure sugar dissolves in water but insoluble impurities do not dissolve.
(ii) Adulteration of chalk powder, washing soda in sugar
To small amount of sugar in a test-tube, add few drops of dil. HCl. Brisk
effervescence of CO2 shows the presence of chalk powder or washing soda in
the given sample of sugar.
AIM - 3
To detect the presence of
adulterants in samples of chilli powder, turmeric powder and pepper
REQUIREMENTS: Test-tubes, conc.HCL , dil. HNO3,
KI solution.
PROCEDURE: Common adulterants present in
chilli powder , turmeric powder and pepper are red coloured lead
salts, yellow lead salts and Dried
papaya seeds respectively. They are detected as follows .
(i) Adulteration of red lead salts in chilli powder
To a sample of chilli powder, add dil. HNO3. Filter the solution and add 2
drops of potassium iodide solution to the filtrate. Yellow ppt. indicates the
presence of lead salts in chilli powder.
(ii) Adulteration of yellow lead salts to turmeric
powder
To a sample of turmeric powder add conc. HCl. Appearance of magenta colour
shows the presence of yellow oxides of lead in turmeric powder.
(iii) Adulteration of brick powder in red chilli powder
Add small amount of given red chilli powder in beaker containing water.
Brick powder settles at the bottom while pure chilli powder floats over water.
(iv) Adulteration of dried papaya seeds in pepper
Add small amount of sample of pepper to a beaker containing water and stir
with a glass rod. Dried papaya seeds being lighter float over water while pure
pepper settles at the bottom.
RESULTS
Selection of wholesome and non-adulterated food is essential for daily life
to make sure that such foods do not cause any health hazard. It is not possible
to ensure wholesome food only on visual examination when the toxic contaminants
are present in ppm level. However, visual examination of the food before
purchase makes sure to ensure absence of insects, visual fungus, foreign
matters, etc. Therefore, due care taken by the consumer at the time of purchase
of food after thoroughly examining can be of great help. Secondly, label
declaration on packed food is very important for knowing the ingredients and
nutritional value. It also helps in checking the freshness of the food and the
period of best before use. The consumer should avoid taking food from an
unhygienic place and food being prepared under unhygienic conditions. Such
types of food may cause various diseases. Consumption of cut fruits being sold
in unhygienic conditions should be avoided. It is always better to buy
certified food from reputed shop.
BIBLIOGRAPHY
Books used :-
Chemistry Lab manual
Source used:-
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