L-Cysteine (E920) from human air

Here's some findings about what L-Cysteine is produced from.

What is it and where is it used?
L-Cysteine is a non essential amino acid used in bakery products as dough conditioner. It helps keep the dough from shrinking in case of pizza crust and pita breads. It is also used in bagels. It also reduced mixing time. L-Cysteine is made from either human hair, chicken feathers and synthetic material.

One leading amino acid supplier reported to us in February 2011 that "duck feathers or human hair" were the sources, based on an official statement received from its Chinese supplier.
A product manager with another food ingredients company reported to The VRG in August 2010 that "it’s not human hair, not duck feathers, that’s the major source of L-cysteine today; it’s hog hair." He estimated hog hair to be the source of 90% of the Chinese L-cysteine supply.
A manager of company that produces non-animal L-cysteine stated in September 2010 that the major animal source of L-cysteine today was "human hair mostly" followed by "duck feathers or hog hair when the human hair supply was low." According to this source, feathers and hog hair "are reportedly inefficient compared to [human] hair [in yielding great quantities of L-cysteine]. So if there is a problem with hair [supply], then hog hair or feathers may be a backup."

- March 09, 2011 vrg.org

And more...

We reported the human and animal origins of L-cysteine in The Vegetarian Resource Group's Dictionary of Food Ingredients ten years ago. Then, the most common source was human hair found on the floors of Chinese barbershops. Today, it is derived from Chinese duck feathers approximately 80% of the time (estimation based on values given by several companies that manufacture and sell L-cysteine).
L-cysteine is considered a substance that is generally recognized as safe by the Food and Drug Administration. It must be labeled by its "common and usual name," (i.e., "L-cysteine"), on food packages, even if present in very small amounts, as long as it has a functional effect in foods. In other cases, such as when it is used to make flavors that are in foods, it does not have to be labeled. When L-cysteine does have to be labeled, its source does not have to be specified according to the FDA. While researching L-cysteine, The VRG asked several fast food chains and a major vegetarian food company about the sources of L-cysteine in their products. McDonald's told us that L-cysteine derived from duck feathers is in their Honey Wheat Roll, the Deluxe Warm Cinnamon Roll, and the Baked Apple Pie. The L-cysteine in several items offered at Dunkin' Donuts is also derived from duck feathers. Burger King told us in June 2007 that it "could not guarantee" the source of L-cysteine in its products.
On the other hand, Subway recently announced in March 2007 that it has removed the L-cysteine from its otherwise animal product-free Carb Conscious Wrap. When asked about the source of L-cysteine in several of its products, Domino's Pizza told us that L-cysteine is "microbially derived" in its Hand-Tossed Crust and informed us that the L-cysteine in Domino's Breadsticks, Cheesy Bread, and Cinna Stix is "vegetable-derived."
The public relations firm for Morningstar Farms told us that the L-cysteine in their Veggie Bites Country Scramble, Veggie Bites Spinach Artichoke, and Veggie Bites Eggs Florentine was a "microbial fermentation product."
2007 - vrg.org

And more...

The possibility that human hair may be used in bread relates to the existence of an
animal-based flour additive called L-Cysteine. It is an amino acid which is used as a
flour improver. It is known as E920 and is permitted for use in all biscuits, breads
and cakes except those that claim to be wholemeal. 

The problem with E920 is that even when it is used it doesn’t have to be listed in the ingredients that’s because it is broken down in the baking process so the manufacturers argue that doesn’t constitute an ingredient. The Food Standards Agency denies this, It says that L-Cysteine must always be labelled. Indeed, the industry says the reason you so rarely see E920 on labels is that these days it is very rarely used (apparently it was much more common fifteen years ago).and that the only L-Cysteine their members would use is the synthetic variety. However the European regulation specifies that only L-Cysteine produced from duck and chicken feathers or from pig bristles can be used. That means that, so long as your daily bread was baked in Europe, it almost certainly does not include human hair but the question is that not suitale for the Muslim consumer unless duck and chicken feathers are from animals Halal slaughtered in accordance with the Islamic Shariah Law.  

(ref)

L-Cysteine in Domino’s Pizza: “Non-Animal” According to Domino’s. (ref)

And more fastfood details. (ref)

Your pizza might have human hair without you realizing it. The consumption of human hair comes in the form of L-cysteine an additive that is cheaper than other forms such as petroleum. This ingredient makes dough softer, stronger, and faster to bake. L-cysteine is found in an innumerable amount of products ranging from pizza dough to supplements. "L-cysteine may be present in a number of foods, but it is not always listed on the ingredients," says Richard Ratcliffe, the executive secretary of the British Food Additives and Ingredients Associations. (ref)

From a 2010 article on BBC News:


The thought may be an appetite killer, but human hair can be used to make an additive that is found in foods such as the dough for pizza crusts and bagels.
Your mop top is a rich source of L-cysteine, an amino acid that can be extracted from hair and used as a flavour enhancer or flour improver. It is sometimes listed as E920 on food packaging. As well as being found in dough it can be used to give food a meat-like flavour, especially in dog food.
Ten to 15 years ago human hair was a main source of L-cysteine. Producers, mainly based in China, extracted it from hair clippings from salons, even strands collected from hairbrushes.

But as people became more aware of what was in their food, they simply didn't like the thought of human hair having anything to do with what they ate. More Chinese people also started perming their hair, which made extracting the amino acid more difficult.
"As more people found out where L-cysteine came from they thought 'yuck, human hair, don't fancy that'," says a spokesman for Premium Ingredients, a major distributor of ingredients for the food, fragrance and pharmaceutical industries.
"It was also extracted from mainly Chinese hair because it is straight, making the process much easier and cheaper. But more and more people started using perm lotions which made the process more complicated and costly."
Now L-cysteine comes mainly from chicken and duck feathers, which can be collected in larger quantities than hair. In recent years it has also started to be manufactured synthetically. Premium Ingredients, for one, no longer uses human hair.
"People find this more palatable," says the spokesman. The synthetic stuff can also be eaten by vegans and is considered by most to be halal and kosher.



On wikipedia. (ref)