What is Riboflavin?
Riboflavin is a nutrient necessary for maintaining good health in humans and animals. It is also commonly refered to as vitamin B2.
As a food additive, it is used as an deep yellow – orange – red food colouring. Note that “flavin” comes from the Latin word for yellow, “flavus”.
Riboflavin is a water soluble vitamin produced by plants and many micro-organisms. Humans cannot produce riboflavin even though it is essential to life. Insufficient riboflavin (called Ariboflavinosis) can result in loss of hair, inflammation of the skin, vision deterioration, and growth failure.
Industrially, it can be produced by a variety of bio-technologies using fungus or bacteria. Some types of bacteria (Bacillus subtilis) have actually been genetically modified to increase their riboflavin production.1
Riboflavin can be difficult to incorporate into most foods due to poor solubility and because it degrades quickly when exposed to sunlight.
When used to fortify foods, typical products include cereals, sauces, vitamin supplements, soups.
As a food colouring, it is commonly found in candy.
Health Issues / Side Effects:
We need riboflavin to survive, so it is probably quite safe as a food additive, especially in the small quantities required for food colouring.
In some people, riboflavin may cause urine to turn a darker yellow-orange colour. When consumed in high amounts, it may cause diarrhea and/or an increase in urine.2
There are actually two types of riboflavin used as colouring agent. The E Numbers are 101 and 106.
Riboflavin 5′-phosphate has an E Number of 101a. It is sometimes used because it is more soluble.
Riboflavin 5′-sodium phosphate has an E Number of 106.
I have not been able to find any product that lists riboflavin as an ingredient specifically added to provide colour. It is hard, because Canada does not require product labels to specifically state what kind of food colouring is used.
If anybody knows of such a product (in any country) please leave a comment.