On Wed, 17 Nov 1999, Ray Audette wrote:
> > On Mon, 15 Nov 1999, Erik Hill wrote:
> > > What are some of the bigger antioxidants?
> >
> Stearic acid has been found to be one of the best antioxidants known.
> Stearic acid is found in animal fats.
Since first reading this claim in Neanderthin I have been unable
to find much literature on the antioxidant properties of stearic
acid. However, I don't doubt the claim, since this is apparently
one of the things that makes rendered suet fat (which is
relatively high in stearate) so stable and suitable for making
pemmican. After all, tallow is about 10% PUFA, which is highly
oxidation-prone, but something prevents the pemmican from
becoming rancid, and the stearic acid is a good candidate.
I would be interested to know if there is much stearate in
coconut oil, which is also seemingly very oxidation-resistant.
Stearate is a hard fat. Candle-makers may use it as an additive
to make candles harder.
Another interesting thing that I have in my nutritional x-files
is a number of articles indicating that stearic acid is
relatively difficult to digest, making it a "low-calorie" fat.
The article below is an animal study, but I have found human
studies that make essentially the same point.
Note that the real purpose of the research described is to
produce a shortening for baking that is free of trans-fats.
Todd Moody
[log in to unmask]
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Effect of Shortenings Containing Stearic Acid on Blood Lipids and Fat
Digestibilities in Hamsters
Cereal Chem. 75(4):557-559
Publication no. C-1998-0605-02R
Effect of Shortenings Containing Stearic Acid on Blood Lipids and
Fat Digestibilities in Hamsters.
G. S. Ranhotra (1,2), J. A. Gelroth (1), S. D. Leinen
(1), and T. W. Ricklefs (1).
(1) Nutrition Research Program,
American Institute of Baking, 1213 Bakers Way, P.O. Box 3999,
Manhattan, KS 66505-3999.
(2) Corresponding author. Phone: 785/537-4750. Fax: 785/537-1493.
E-mail: [log in to unmask]
Accepted March 30, 1998.
Copyright 1998 American Association of Cereal Chemists, Inc.
Tristearin (TS), a stearic acid-rich hard fat, and soybean oil
(SO) were blended in different ratios to produce four functional
shortenings (blends) for use in foods. Groups of hamsters were
then fed diets containing TS, SO, and the four blends for four
weeks. After four weeks, serum total cholesterol (CH) levels
were measured: the group fed SO had 219 ± 19 mg/dL, and the
groups fed four blends had a range of 214 ± 14 to 222 ± 15 mg/dL.
Thus, TS in the blends exerted no hypercholesterolemic effect; it
even lowered serum triglycerides (SO vs. blends). Liver CH levels
were significantly lower only in the group fed the blend
containing the highest level (60%) of TS. While SO was nearly
completely digested (97.7%), digestibility of TS in the blends
was low with a range of 10.2-26.3%, which was inversely related
to the level of TS in the blend. Thus, functional shortenings
produced by blending TS with edible oils may not only not raise
blood CH levels, but they would be free of trans fatty acids and
may be classified as reduced-calorie fats.
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