Page 105 - Natural Antioxidants, Applications in Foods of Animal Origin

84 Natural Antioxidants: Applications in Foods of Animal Origin
VetBooks.ir “Dietary Supplement Health and Education Act of 1994” and are considered

to be one (or more) of several defined dietary ingredients a vitamin, a mineral,
an herb or other botanical, amino acid, a dietary substance for use by man to
supplement the diet by increasing the total dietary intake, or a concentrate,
metabolite, constituent, extract, or combination of any ingredient described
in clause (A), (B), (C), (D), or (E) and is excluded from regulation as a food
additive. Extracts, concentrates, and resins are also regulated under the Food
Labeling Regulation, Amendments; Food Regulation Uniform Compliance
Date; and New Dietary Ingredient Premarket Notification Final Rule (1997).
If they are added to cause flavor or color changes, they are regulated as such
and specific quantities allowable for use in various foods are set forth. Based
on the number of various classifications under which an extract, concentrate,
or resin could be covered, allowable use levels vary widely (Brewer, 2011).

2.18 CONCLUSION
Plant and animal tissues contain unsaturated fatty acids, primarily in the
PL fraction of cell membranes. These lipids are especially susceptible to
oxidation because of their electron deficient double bonds. The breakdown
products of oxidation can produce off-odors, new flavors, loss of nutrient
content, and color deterioration. To manufacture high-quality, stable food
products, the most effective solution is often the addition of antioxidants,
either synthetic or natural, which can serve as “chain breakers,” by inter-
cepting the free radicals generated during various stages of oxidation or to
chelate metals. Chain-breaking antioxidants are generally the most effec-
tive. A common feature of these compounds is that they have one or more
aromatic rings (often phenolic) with one or more −OH groups capable of
donating H to the oxidizing lipid. Synthetic antioxidants, such as BHA,
·
BHT, and PG, have one aromatic ring. The natural antioxidants AA and α-T
each have one aromatic ring as well. However, many of the natural anti-
oxidants (flavonoids and anthocyanins) have more than one aromatic ring.
The effectiveness of these aromatic antioxidants is generally proportional
to the number of −OH groups present on the aromatic ring(s). Depending
on the arrangement of the −OH groups, these compounds may also chelate
pro-oxidative metals. The facts that they are natural, and have antioxidative
activity that is as good or better than the synthetic antioxidants, make them
particularly attractive for commercial food processors because of consumer
demand for natural ingredients.