We as Muslims are usually vigilant about checking the ingredient lists of personal care products and food items for (non-kosher) gelatin or alcohol so that we can avoid them but other ingredients are often neglected such as Stearic acid, Palmitic acid or Glycerin. So what exactly are Stearic, Lauric, Myristic, Oleic, and Palmitic acids? They are all names for fatty acids which are produced either from natural fats and oils that are added to soaps, cosmetics, personal care products, and some foods including margarine, shortening and other baking ingredients but very frequently they are obtained from a slaughterhouse by-product known as tallow or animal fat.
Animal waste – the stuff that slaughterhouses can't use, the stuff that's not even good enough to make it in to hot dogs--are sent to places called rendering plants. Sometimes animal shelters will send euthanized dogs and cats to rendering plants. I've even heard of road kills being sent to these rendering plants which is outright disgusting! So what happens to these poor animals in the rendering plants? The dead carcasses and parts are separated meat from fat, bone from skin, and so on. The fat is then used to create cosmetic ingredients such as stearic acid.
PETA states about Stearic acid: "When animal-derived, a fat from cows, pigs, and sheep and from dogs and cats euthanized in animal shelters, etc. May also be of plant origin, including from cocoa butter and shea butter. Can be harsh, irritating." http://www.peta.org/living/vegetarian-living/animal-ingredients-list.aspx
Stearic acid – one of the most common fatty acids, especially in soaps – is a wax-like fatty acid, frequently sourced from tallow, with smaller amounts obtained from herrings and sardines. Almost all stearic acid in the US is made from tallow and coconut oil, with smaller amounts coming from palm oil. In addition to soap making, stearic acid is used to form stable creams, lotions and ointments. It is also frequently used in products such as deodorants and antiperspirants, foundation creams, hand lotions, hair straightening products, and shaving creams.
Glycerin or Glycerol is a byproduct of soap manufacturing, and can be either synthetic, or derived from plants (usually soybeans) or animals (usually tallow). It can also be a blend of both animal and vegetable oils. Glycerides (mono/di/and tri) tend to be derived from animal fats, and are used frequently by the food industry.
A 2010 report from The Vegetarian Resource Group found that glycerin is usually derived from plant materials when used in food. However, especially in the case of cosmetics and in bath and body products, this is not a guarantee, so unless the label lists the ingredient as ‘vegetable glycerin’ it is advisable to contact the company.
In conclusion, if we see any of these terms: Oleic, Palmitic, Stearic, Palmitoleic, Linoleic, Myristic acid or Glycerin in an ingredients list, it might be a substance sourced from animal tallow (or another animal-based source), and it would be wise to contact the company to find out the ingredient’s origin.
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