Daily Milk and Product Test Reports

We Strictly follows FSSAI regulations and Process.

Test 1: Added Sugar

Principle: Resorcinol reacts with sugar to produce a distinct color change.
Procedure:
1. Take 5 ml of the milk sample.
2. Add 2 ml of Resorcinol.
3. Place the mixture in a boiling water bath for 5 minutes.

Results:
- Positive: A brick-red color indicates the presence of added sugar.
- Negative: The solution remains a milky white color.

Test 2: Added Starch

Principle: Iodine solution reacts with starch to form a blue-black color.
Procedure:
1. Take 3 ml of milk.
2. Bring it to a boil and cool it down to tap water temperature.
3. Add 3 drops of a 10% acetic acid solution.
4. Add 0.2 ml of iodine solution.

Results:
- Positive: A blue or dark blue color indicates the presence of added starch.
- Negative: The solution remains a milky white color.

Test 3: Added Salt (Sodium Chloride)

Principle: Silver nitrate reacts with chloride ions to form a precipitate, which is then visualized with potassium chromate.
Procedure:
1. Take 5 ml of the milk sample.
2. Add 2 ml of a 0.1N silver nitrate solution.
3. Add 0.5 ml of a 10% potassium chromate solution.

Results:
- Positive: A yellow color indicates the presence of added salt.
- Negative: The solution remains a brown-red color.

Test 4: Neutralizers

Principle: Phenolphthalein is an indicator that changes color in the presence of alkaline substances (neutralizers).
Procedure:
1. Take 4 ml of milk in a test tube.
2. Add 1 ml of a phenol red solution.

Results:
- Positive: A pinkish-orange color indicates the presence of neutralizers.
- Negative: The solution remains a yellow color.

Test 5: Maltodextrin

Principle: Maltodextrin breaks down, and the resulting components react with iodine to show a color change.
Procedure:
1. Take 20 ml of the milk sample and boil it between 70-80°C.
2. Add a few drops (1.5 to 2 ml) of a 5% citric acid solution, cool, and filter the mixture.
3. Take 5 ml of the filtrate.
4. Add 0.25 ml of iodine solution.

Results:
- Positive: A red-brown color indicates the presence of maltodextrin.
- Negative: The solution remains a pure yellow color.

Test 6: Added Urea

Principle: A DMAB reagent reacts with urea to produce a yellow color.
Procedure:
1. Take 5 ml of the milk sample.
2. Add 2 ml of a 1.6% DMAB reagent solution.
3. Mix well.

Results:
- Positive: A dark yellow color indicates the presence of added urea.
- Negative: The solution is only a slight yellow color.

Test 7: Detergent

Principle: Detergent separates from milk fat and reacts with other chemicals to produce a blue color.
Procedure:
1. Take 2.5 ml of the milk sample.
2. Add 7.5 ml of methanol.
3. Filter the contents using Whatman No. 1 filter paper.
4. Add 2 ml of the filtrate to a test tube, then add 2 ml of a methylene blue solution and shake well.
5. Add 4 ml of chloroform and mix gently 5 times.
6. Allow the mixture to settle for 10 minutes.

Results:
- Positive: A dark blue color indicates the presence of detergent.
- Negative: The solution is a light blue color.

Test 8: Hydrogen Peroxide (H₂O₂)

Principle: Hydrogen peroxide reacts with paraphenylenediamine to produce a blue-gray color.
Procedure:
1. Take 2 ml of milk.
2. Add 2 drops of a 2% paraphenylenediamine solution.
3. Mix well.

Results:
- Positive: A blue or gray color indicates the presence of hydrogen peroxide.
- Negative: The solution remains a milky white color.

Test 9: Formaldehyde

Principle: Ferric chloride and sulfuric acid react with formaldehyde to produce a distinct violet ring.
Procedure:
1. Take 5 ml of milk and 5 ml of distilled water.
2. Add 0.1 ml of a 10% ferric chloride solution.
3. Add 3 ml of an 80% sulfuric acid (H₂SO₄) solution. Keep the tube sideways and add the acid slowly down the side.
4. Wait for 5 minutes.

Results:
- Positive: A violet ring indicates the presence of formaldehyde.
- Negative: The solution remains a milky white color.

Test 10: Foreign Fat

Principle: The refractive index of milk fat is different from that of vegetable oils or other foreign fats.
Procedure:
1. Extract ghee from the milk sample.
2. Put the ghee on the prism of a butyro-refractometer at 40°C.
3. Correct the reading using the formula: Corrected B.R. = Observed B.R. Reading × 1.08.

Results:
- Positive: A corrected B.R. reading of 43 or less indicates the presence of foreign fats.