Adulteration of Food
Adulteration of Food
Meaning
“Adulterant” means any material which is or could be employed for making the food unsafe or sub-standard or misbranded or containing extraneous matter.
Food Adulteration is an act of intentionally debasing the quality of food offered for sale either by the admixture or substitution of inferior substances or by the removal of some valuable ingredient.
Food is declared adulterated if :
- A substance is added which depreciates or injuriously affects it.
- Cheaper or inferior substances are substituted wholly or in part.
- Any valuable or necessary constituent has been wholly or in part abstracted.
- It is an imitation.
- It is coloured or otherwise treated to improve its appearance or if it contains any added substance injurious to health.
- For whatever reasons its quality is below the Standard.
Adulterated food is dangerous because it may be toxic and can affect health and it could deprive nutrients essential for proper growth and development.
Adulteration in Milk
The list of common adulterants and their method of detection is given below:
- Water
Method of Detection:
- The presence of water can be detected by putting a drop of milk on a polished slanting surface. The drop of pure milk flows slowly leaving a white trail behind it whereas milk adulterated with water will flow immediately without leaving a mark.
- Starch
Method of detection
- Add a few drops of 1% Iodine solution. Formation of blue colour indicates the presence of starch.
- Urea
Urea is generally added in the preparation of synthetic milk to raise the SNF (Solid not Fat) value.
Method of Detection
- Five ml of milk is mixed well with 5 ml paradimethyl amino benzaldehyde (16%). If the solution turns yellow in colour, then the given sample of milk is added with urea.
- Take 5 ml of milk in a test tube and add 0.2 ml of urease (20 mg / ml). Shake well at room temperature and then add 0.1 ml of bromothymol blue solution (0.5%). Appearance of blue colour after 10-15 min indicates the adulterationmilk with urea.
- Vanaspati
Method of detection
- Take 3 ml of milk in a test tube. Add 10 drops of hydrochloric acid. Mix up one teaspoonful of sugar. After 5 minutes, examine the mixture. The red colouration indicates the presence of vanaspati in the milk.
- Formalin
Formalin (40%) is poisonous though it can preserve milk for a long time.
Method of detection
- Take 10 ml of milk in test tube and 5 ml of conc. sulphuric acid is added on the sides of the test tube with out shaking. If a violet or blue ring appears at the intersection of the two layers, then it shows the presence of formalin.
