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Lecithins play
an important role in animal nutrition, too. Also classified as “secondary plant metabolites”, these
substances are known to have a positive effect in the nutrition of pigs and poultry, and especially in
fish farming. And there are indications that lecithin produces good results in cattle feeding, too.
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Improving digestibility
In animal nutrition lecithins are used as
emulsifiers. They improve the digestibility
of the feed fats and fat-soluble vitamins.
The substances used are either “crude
lecithins” obtained directly from vegetable
fats, for example soybean oil, or “deoiled
lecithins” produced by means of extraction.
With an oil content of 35 – 40%,
crude lecithins” have a rather viscous
consistency, whereas “deoiled lecithin”,
which contains a very high proportion of
phospholipids (at least 95%), is available
in powder form. Being highly concentrated
it is also highly effective. This has
been documented in numerous scientific
studies.
Liquid or powder?
Deoiled lecithin is the most economical
dosage form for feed. Liquid crude lecithin
is used mainly as a raw material for
other lecithin powders on carriers. These
powders are made up on the basis of various
carriers for different technical appli-
cations. In this consistency they are easier
to transport and dose. For technical reasons
the phospholipid content in these
lecithin powders on carriers is reduced to
about one-third.
The chemical background
From the chemical point of view, lecithins
belong to the phospholipids with the
groups of substances important for metabolism.
The latter include phosphoric acid,
glycerol, choline, inositol and also unsaturated
fatty acids such as linoleic and
linolenic acid. They have a characteristic
structure with a hydrophilic or polar group
and a hydrophobic or non-polar group.
The former includes choline, inositol, glycerol
and phosphoric acid, while the latter
comprises unsaturated fatty acids. This
polar structure makes lecithins excellent
emulsifiers which can be used for stabilizing
both oil-in-water and water-in-oil
emulsions.
A diversity of effects
The effects of lecithin fall into both physical-
technical and biochemical-physiological
fields. The physical-technical effects
can be described by the terms emulsifier,
dispersant, releasing agent and waterbinding
capacity. The physiological effects
are concerned with the metabolism of
lipoproteins, phospholipids, triglycerides
and cholesterol of various densities (HDL,
LDL, VLDL) for the intermediate trans-
portation of fats. When added to fattening
feed for pigs, lecithin permits much better
conversion of fat and thus improved fattening performance. But lecithin is not only
beneficial in pig fattening. In milk substitutes it facilitates the feeding of calves
and piglets, and it produces good results in broiler
fattening and fish farming.
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