Riboflavin (Vitamin B2)

Riboflavin (E101), also known as Vitamin B2, is a naturally occurring water-soluble vitamin used in food manufacturing as a yellow colourant. It is found abundantly in milk, eggs, liver, and green leafy vegetables, and its presence in food as an additive is chemically identical to its dietary form. It produces a characteristic greenish-yellow fluorescence in solution, making it suitable for colouring certain beverages, dairy products, infant formula, and some processed foods.

JECFA evaluated riboflavin in 1974 and assigned an ADI designated as "not specified" — meaning the committee found no evidence of harm at any level of intake achievable through food additive use. This classification is reserved for substances with a long history of safe use and a toxicological profile that gives no cause for concern. No numerical upper limit was considered necessary. EFSA OpenFoodTox 3.0 does not list riboflavin in its reference value database for food additive use.

Riboflavin is permitted as a food colour in the EU, United States, Japan, South Korea, and most global food systems. Because it is an essential nutrient, there is no practical concern about overconsumption from food colouring applications; intakes from additive use are modest relative to normal dietary exposure. Consumers with riboflavin-fortified foods in their diet effectively receive an added nutritional benefit alongside any colouring function, making it one of the more benign entries in the food additive lexicon.