Vegetable lecithins composition

Table 10.1 Phospholipid composition in % of liquid vegetable lecithins by 31P-NMR...

Table 10.2 Fatty acid composition in % of vegetable lecithins ...

Highly concentrated emulsions are also evident in everyday applications. A classic example is mayonnaise, in which a large volume of vegetable oil is emulsified in a small amount of vinegar, using lecithin from egg-yolk as the emulsifier. In addition, HIPEs are most probably found in many cosmetic products, especially gels and creams. However, little information is available on products of commercial importance, so one can only speculate on their exact nature and composition. 

Triglycerides, lecithin, and ergosterol are the main constituents of yeast lipid (feu. Oleic and palmitic acids predominate in yeast fet. These resemble the composition of common vegetable fats. Ergosterol. the precursor of calciferol (vitamin D2) varies from 1 to 3% of yeast dry matter. 

In a patent obtained by Gautchier and Dyer (221), a fat-sparing composition is described that may be used to extend vegetable fat in cookie filler cremes and other cremes. The patent states that lecithin may be advantageously used in that composition. In a similar patent, Abboud (222) used lecithin in a fat replacement composition for ready-to-spread frosting. 

Glycerophospholipids (PL) are abundant lipid components found in Nature [1]. Most vegetable oils, fish oil and egg yolk are particularly rich in mixtures of phospholipids. They are characterized by the presence of a polar head and two fatty acid chains in the apolar part of the molecule. The two acyl chains mainly consist of saturated fatty acid residues in the snl position and mainly (poly)unsaturated fatty acid chains in the sn2 position. Mixtures of phospholipids at low cost are obtained from the degumming process of vegetable oils. Lecithin, the main component of the mixture, has the polar head characterized by the choline residue. It is usually defined as phosphatidyl choline (PC) and it is understood that the composition of the apolar part is composed of mixtures of fatty acid residues dependent to a large extent on the source of the raw material (fatty acid chains composition of PC from soy beans palmitic 11.6%, stearic 3.4%, oleic 4.6%, linoleic 66.4%, linolenic 8.7%). Scheme 1 shows a PC with two defined acyl chains at the glycerol backbone l-palmitoyl-2-linoleoyl-5n-glycero-3-phosphocholine (PLPC). 

The production of lecithin from soybeans is described in Section 5.4. Lecithin is the commercial name given to a mixture of phospholipids, naturally occurring in animal or vegetable products such as egg yolk (8-10% phospholipids), butter (0.5-1.2%), wheat lipids (approx. 0.5%) soybean (1.5-3%) and other oil seeds. More details on the chemical composition and physical properties of lecithin appear in Sections 2.3,3.11,6.3,8.10 and 11.2. 

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