Detection of Adulterated Foods
Simple household methods to check common food adulteration.
- Water Adulteration: Put a drop of milk on a polished surface. Pure milk flows slowly leaving a white trail; adulterated with water flows quickly without a trace.
- Starch Adulteration: Add 2 drops of iodine solution. Blue color → starch present.
- Detergent Adulteration: Shake milk. Persistent foam indicates detergent.
- Water Test: Add a spoon of honey in a glass of water. Pure honey settles at the bottom, adulterated dissolves quickly.
- Heat Test: Heat a small amount. Pure honey caramelizes but does not foam; adulterated foams strongly.
- Chicory Adulteration: Sprinkle coffee powder in water. Chicory sinks quickly; pure coffee floats.
- Starch Test: Add iodine to a coffee solution. Blue color indicates starch adulteration.
- Argemone Oil: Add a few drops of nitric acid. Reddish-brown color shows adulteration.
- Freezing Test: Pure oils solidify evenly on cooling. Uneven solidification → adulterated.
- Turmeric (lead chromate): Mix turmeric in dilute hydrochloric acid → forms yellow precipitate if adulterated.
- Red chili powder (brick powder): Mix with water → adulterated powder settles quickly.
- Artificial dyes:Dip in alcohol or water → colors dissolve if artificial.
- Exhausted leaves: Brew tea → weak color and taste indicate poor quality.
- Synthetic colors: Boil in water → unnatural color dissolves.
- Foreign leaves: Examine visually → presence of small stems, sticks, or different leaves.
- Dye: Soak in water → Water turns green if dye is present.
- Chemical colors: Rub on paper → Green stains show chemical coloring.
- Papaya Seeds: Put in water → Papaya seeds float; real pepper sinks.
- Chemicals: Artificially ripened fruits are bright yellow outside but raw inside.
- Chemicals: Keep in water → Such fruits float unnaturally.