Behenic acid: structure, properties, and food sources

Behenic acid (22 carbon atoms) is a major component of Ben oil, also known as behen oil or Moringa oil (first reported by Voelcker A. in 1848), which is extracted from the seeds of Moringa oleifera and is used in cosmetics.
The name “behenic” derives from the Persian mount Bahman, where the seeds of this tree were harvested.
It belongs to the group of saturated fatty acids (no double bond, so its shorthand notation is 22:0). It is also a member of the group called very long chain fatty acids (VLCFA), from 20 carbon atoms onwards.

PROPERTIES
Molecular weight: 340.58356 g/mol
Molecular formula: C22H44O2
IUPAC name: docosanoic acid
CAS registry number: 112-85-6
PubChem: 8215

Skeletal formula of behenic acid, a saturated fatty acid
Behenic Acid

In purified form it is a white to yellowish waxy solid, with melting point at 79.95 °C (175.91 °F; 353.1 K) and boiling point at 306 °C (582.8 °F; 579.15 K) at 60 mm Hg.
A curiosity: it is often used to give hair conditioners and moisturizers their smoothing properties.

OTHER NAMES
docosoic acid
1-docosanoic acid
N-docosanoic acid
22:0

Food sources of behenic acid

It occurs in small quantities, as ester of glycerol, only in some fats and oils.
It is not found in fresh red and white meat.
It is absent in processed and preserved meats, except some kinds of ham, where it is found in very small quantities, such as in San Daniele ham, 0.01 g/100 g of edible portion, or in trace, such as in Parma ham.
It is absent in milk and dairy products, including butter.
It is not present in eggs.
In fishery products, it is present in very small amounts only in belly of tuna in brine, 0.01 g/100 g of edible portion.
On the contrary, it is present in appreciable quantities in a few vegetable fats and oils:

  • the highest amount is found in peanut oil, 3.25 g/100 of edible portion; small amounts are present in wheat germ oil and olive oil, 0.1 and 0.09 g/100 g of edible portion, respectively;
  • peanut butter contains 1.28 g/100 g of edible portion; it is absent in margarine.

It is not found in cereals and cereal products.
It is absent in fruit, even in dried oily ones.
It is not found in fresh and dried legumes, but it is present in small amounts in soy meal, 0.02 g/100g of edible portion.

References

  1. Akoh C.C. and Min D.B. “Food lipids: chemistry, nutrition, and biotechnology” 3th ed. 2008
  2. Chow Ching K. “Fatty acids in foods and their health implication” 3th ed. 2008