Groundnut Oil (Peanut Oil) Safety Inspection

Groundnut oil is often adulterated with toxic Argemone oil or cheaper oils like cotton seed and rice bran oil to increase profit margins. 1. The Nitric Acid Test (Argemone Detection): In a test tube, take 5ml of groundnut oil and add a few drops of concentrated nitric acid. Shake gently and warm the mixture for 2-3 minutes. If the oil layer turns reddish-brown or orange, it is contaminated with Argemone oil. Pure groundnut oil will not change color. 2. The Refrigeration Test: Place a small bottle of groundnut oil in the refrigerator for 3-4 hours. Pure groundnut oil has a very low freezing point and remains liquid. If you see significant white solidification or "clouding" at the bottom, it indicates adulteration with palm oil or cotton seed oil. 3. The Rub and Smell Test: Rub a few drops of oil on your palms for 30 seconds until they get warm. Pure groundnut oil has a distinct, nutty, and pleasant aroma. If the smell is neutral or feels "fatty" like vegetable ghee, it is adulterated. 4. The Transparency Check: Pure groundnut oil is light golden-yellow and crystal clear. If the oil looks murky, "fluorescent," or has a chemical, sharp smell, suspect industrial dyes or mineral oil treatment.