ADULTERATION

WHAT IS MEANT BY FOOD ADULTERATION?

The contamination of food materials with low quality, cheap, toxic substances is called food adulteration.

What are the ways by which adulteration is affected?

Adulteration is done in the following ways:

a) Addition of inferior substances and poisonous substances
b) Insect infestation
c) Extraction of superior ingredients from the food
d) Addition of coloring matter not permitted by regulations.

What is an Adulterant?
The substance which degrades(or lowers) the quality of a food material is called an adulterant. The adulterants are much cheaper than the concerned foodstuffs. So, selling adulterated food materials can bring a lot of easy money for the dishonest trader, but at the cost of many lives.

Test to detect adulteration in food

Since food adulteration is a serious matter and concerns us all, so we should know how to detect adulteration in the commonly used food items like butter, ghee, edible oil, dals(pulses) and milk. This is discussed below.

1. To detect the presence of vanaspati in ghee or butter

Take 5ml of ghee or butter in a test tube and add 5 ml of conc. HCL and a small amount of sugar. Shake the test tube well. Appearance of a deep red colour in the lower layer shows the presence of vanaspati in ghee.

2. To detect the presence of starch in milk and butter

A small amount of iodine is added to the adulterated sample. The appearance of the colour shows the presence of starch in the sample.

3. To detect the presence of chicory powder in coffee powder

Take equal volumes of conc. HCl and coffee decotion in a test tube and heat for few minutes. Then, add small quantity of seliwonoff reagent. The red colour formed shows the concentration of chicory powder mixed.

4. To detect the presence of argemone oil in edible oil

Take 5 ml of edible oil in a test tube and add some conc. HNO3 to it. Shake the test tube carefully and observe the colour of the lower layer(the acid layer). Appearance of a reddish-brown in the acid layer shows the presence of argemone oil in the edible oil.

5. To detect the presence of metanil yellow in dal

Take about 5 grams of dal in a test tube and then add about 5 ml of water. Shake the test tube well. Then add a few drops of conc. HCl to the test tube. Appearance of a pink colour in the solution shows the presence of metanil yellow in dal.

6. To test the presence of water in milk

VISCOSITY TEST:
When pure milk is adulterated by mixing water, then its viscosity decreasing that is, it becomes very thin and flows easily on a surface. This fact can be used in testing the presence of water in milk, as follows:

Take a drop of the milk sample on a glass plate and hold the glass plate vertically.

a) If the drop if milk either keeps sticking to the glass plate or flows down slowly, leaving behind a white trail, then the milk sample is pure.
b) If the milk drop run down quickly on the glass plate, leaving no white trail, then the milk has been diluted with water.


-Surenthiran