Composition | Source | Production | Types | Uses | Safety | FAQs
Stearic acid or octadecanoic acid, a most common saturated fatty acid (without double bonds) with the chemical formula C₁₇H₃₅COOH. It occurs naturally as a glyceride in both animal fats & oils and vegetable oils. When used in food, it has the European food additives number E570.
Stearic acid and/or its derivatives can be used as a surfactant, emulsifier, and lubricant in food, cosmetics, pharmaceuticals, candles, rubbers, plastics and etc.
What is it Made of?
The main compositions in commercial stearic acid are stearic acid and palmitic acid, although pure stearic acid is also available. Their assays differ based on the purity or grade of stearic acid.
Similar with its food grade, per the USP definition, its USP-NF grades can be divided into three types according to the content of stearic acid as follows ():
- Type 50: stearic acid (40.0%–60.0%), stearic acid + palmitic acids: NLT 90.0%.
- Type 70: stearic acid (60.0%–80.0%), stearic acid + palmitic acids: NLT 90.0%.
- Type 95: stearic acid (NLT 90.0%), stearic acid + palmitic acids: NLT 96.0%.
Foods Rich in Stearic acid?
According to the data of National Health and Nutrition Examination Survey (NHANES) in 2005-2006, the following foods are high in stearic acid ():
- Grain-based desserts
- Regular cheese
- Sausage, franks, bacon, and ribs
- Chicken, beef, pork
- Pizza
- Candy
- Pasta
- Eggs
- Butter
- Milk products
- Nuts/seeds
- Potato/corn/other chips
- Quickbreads, crackers
- Soups
Cocoa butter is also high with it.
How is it Made?
Stearic acid is commercially made from hydrolyzing tallow or hydrogenated vegetable oil from edible sources. And follows the process of acid distillation, steaming and pressing.
Here is the general hydrolysis manufacturing process of the triglycerides (stearic acid naturally exist in this form )
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The following are the common sources of animal fats & oils, and vegetable oils.
Animal fats & oils
- Mutton tallow
- Beef tallow
- Lard
- Butter
Vegetable oils
- Palm oil
- Soybean oil
- Coconut oil
- Olive oil
- Corn oil
Commonly the content of stearic acid derived from animal fat (up to 30%) is higher than that from vegetable oils (typically
