Question

Adulterated toor dal which is bright yellow in colour is due to the presence of which of the following substances?
A. Beta carotene
B. Metanil yellow
C. Anthocyanin
D. Propylene glycol

Answer 1

Adulteration of food means addition of another inferior substance to a food item in order to increase the quantity or make it more visually appealing in the eyes of the prospective customer. Adulteration degrades the quality of food. Adulterating foods is illegal and an offence punishable by law. Some of the common adulterants are dyes, vegetable waste products, animal carcasses, low quality flours, wood chips, metal particles etc.

Complete answer:
Option A Beta carotene: Beta carotene is an organic, red-orange pigment found in plants, fruits and some fungi. It is a precursor of vitamin A. Beta carotene is essential for good eyesight and overall health of the body. It is not a food adulterant.
Option A is incorrect.
Option B Metanil yellow: Metanil yellow is a non-permitted food colour used extensively as an adulterant in foods. It provides bright yellow colour to the food which makes it more visually appealing. Long term consumption of metanil yellow causes neurotoxicity in the brain. Its presence can be detected by adding a few drops of HCl to a toor dal. The presence of metanil yellow is indicated by the solution turning pink.
Option B is correct.
Option C Anthocyanin: Anthocyanin is a water soluble vacuolar pigment that, depending on its pH, may appear red, purple, blue or black. Anthocyanins are rich in fruits like blueberry, raspberry, black rice and black soybean. They are permitted to be used as a food colour in the food industry.
Option C is incorrect.
Option D Propylene glycol: Propylene glycol is commonly used as a food additive or ingredient in many cosmetic and hygiene products. It is an excellent solvent and also good at retaining moisture. Due to this, it is used in a variety of processed foods and drinks. It is not a food adulterant.
Option D is incorrect.

Hence, option B. Metanil yellow is the correct answer.

Note:
Several food products are adulterated to increase the quantity and make more profit. The practice of adding adulterants to food products is very common in developing countries and other backward countries. It is recommended to follow certain safety tips to avoid buying adulterated food. Avoiding dark coloured junk and processed foods, washing fruits and vegetables thoroughly in water before use, buying only the food products that have FSSAI validated label etc are some of the precautionary methods.