Know What You Eat: How to Detect Adulterated Food at Home

You don’t need a laboratory to know whether your food has been adulterated. FSSAI has published a free resource — the DART (Detect Adulteration with Rapid Test) book — that documents simple home tests using water, milk, vinegar, and other household items to detect the most common adulterants in Indian foods. Every Indian household that cooks should know these tests. Here are the most important ones.

Before You Start: The Label Check

Before testing, check the label. Under the Food Safety and Standards (Labelling and Display) Regulations 2020, every packaged food product in India must display:

• FSSAI licence number of the manufacturer (14 digits) — absence is a red flag for unverified product
• Complete ingredient list — if you see ‘colour’ listed without a specific permitted colour code (e.g., E102, E110), question it
• Best before / expiry date — both must be clearly printed; avoid products where the date is stamped differently from the printed text (may indicate restamping)
• Country of origin (mandatory under Consumer Protection E-Commerce Rules 2020)
• Veg / Non-veg indicator — green dot for vegetarian, red dot for non-vegetarian (mandatory under FSSAI)

Test 1: Turmeric (Haldi)

Testing for Metanil Yellow (synthetic dye): Add a small amount of turmeric powder (half a teaspoon) to a glass of water. Add a few drops of hydrochloric acid (not available at home — substitute with lime juice or vinegar as an approximate test). Stir. If the colour turns distinctly pink or magenta, Metanil Yellow is likely present. Pure turmeric will not turn pink.

Testing for Lead Chromate: Rub a small amount of turmeric between two wet fingers. Lead chromate will leave a distinct yellow streak on the skin that does not wash off easily with water. Pure turmeric washes off cleanly. A more definitive test: dissolve in water and observe — lead chromate settles as a yellow sediment, while pure curcumin dissolves and gives a uniform colour.

Test 2: Red Chilli Powder

Testing for Brick Dust / Artificial Colour: Add a tablespoon of chilli powder to a glass of water and stir well. Let it stand for a few minutes without disturbing. Pure chilli powder will make the water uniformly red-orange. Brick dust will sink to the bottom as a visible reddish-brown sediment. Artificial dyes (including Sudan Red) will dissolve and turn the water unusually bright red — an intense colour unnatural for chilli.

Test 3: Milk

Testing for Water: Place a drop of milk on a tilted polished surface (glass or a smooth tilted tile). Pure, full-fat milk will flow slowly, leaving a white trail. Watered-down milk will flow fast and leave little to no trace.

Testing for Detergent / Urea: Take 5–10 mL of milk in a tube or glass. Shake vigorously for 30 seconds. Pure milk produces small, quickly dissipating bubbles. If the foam is dense, persists for several minutes, or appears frothy like soap lather, detergent is likely present. For urea: add a soybean powder solution or litmus paper — urea-adulterated milk will turn litmus blue (alkaline).

Test 4: Dal and Pulses

Testing for Artificial Colour: Soak a few dal grains in water for 20–30 minutes. If the water takes on a distinctly coloured tinge — yellow, orange, or pink — artificial colour has likely been added. Pure dal will not significantly colour the soaking water. Another quick test: rub wet dal between your fingers — artificial colour will leave a coloured stain on your fingertips.

Testing for Kesari Dal (Lathyrus sativus): Kesari dal seeds are smaller, flatter, and more irregular in shape than toor dal. Under good lighting, look at a handful of dal — Kesari dal has a distinctly angled, asymmetric shape compared to the rounder, more uniform toor dal. This is a visual test only; confirm through FSSAI’s more detailed kit test if concerned.

Test 5: Honey & Test 6: Ghee

Testing Honey: Add a tablespoon of honey to a glass of water. Do not stir. Pure honey will sink to the bottom as a lump and dissolve slowly when stirred. Adulterated honey (with sugar syrup) will dissolve immediately and cloud the water. Another method is the flame test: dip a matchstick in honey and light it. Pure honey is flammable, but moisture/syrup-adulterated honey will not ignite.

Testing Ghee: Melt the ghee. Good quality pure cow ghee is granular at room temperature and melts into a clear golden liquid. Ghee adulterated with vegetable oils (including palm oil, vanaspati, or partially hydrogenated oils) will appear more uniform in texture, less granular, and may have a slightly different aroma.

The FSSAI DART Book

FSSAI’s DART (Detect Adulteration with Rapid Test) resource covers over 40 common food items with home testing methods. Download it free at: fssai.gov.in. It is available in Hindi, English, and multiple regional languages. Share it with your family — it is one of the most practically useful consumer safety tools ever published in India.