Food additives can refer to a lot of things – flavours, colours, emulsifiers, preservatives… these can be known by their chemical name or their E-number.
For example – E120 is cochineal, E901 is beeswax, E621 is MSG (for a full list http://en.wikipedia.org/wiki/E_number), and vegans get into the habit of scanning food labels to find those additives that are animal derived.
However, there is one additive that is derived from humans, E920 (L-Cysteine) which is produced from human hair.
E920 is an amino acid and is used as an improving agent in flour-based products.
It is used as a ‘dough improver’ or ‘bread improver’. The L-Cysteine is added to the ingredients during the mixing process prior to baking. During mixing, it reacts with a protein in wheat. As the original L-Cysteine amino acid is not present in the final product, by law there is no requirement to list it as an ingredient.
Vegetarian Network Victoria
It is also used in the manufacture of cigarettes, as well as the pharmaceutical and cosmetics industries (one of its names is Keratin)
Traditionally L-Cysteine has been sourced from feathers, pig bristles, but one of the richest sources is Human Hair.
And China, has an entire industry devoted to producing L-Cysteine from human hair.
The amino acid is extracted from the hair and feathers using a fermentation process involving a mutant strain of Escherichia coli (E.coli).
So while VEGANs are very conscious about avoid animal products, the manufacturing industries continue to find new ways to put animal derived ingredients in products, and now, there are human-byproducts to be aware of.