Agriculture Reference
In-Depth Information
Omega-3 fatty acids have clearly been associated with lower rates of chronic
inflammation, reduced risk and treatment of heart disease, lower levels of arthritis,
lower autoimmune disease, and reduced cancer risk (Simopoulos, 1999). Simopoulos
discussed how the expression of multiple genes is influenced by higher ratios of N-3
fatty acids in the diet. The benefits of N-3 fatty acids are further supported by the
observation that reduced cardiovascular risk is observed in populations who con-
sume high levels of N-3 fatty acids. Lack of N-3 fatty acids in the diet can increase
lipogenesis, leading to obesity, and is associated with increased risk of type 2 diabe-
tes, high triglycerides, low HDL, and resultant higher risk of coronary heart disease.
Clearly, increasing the levels of N-3 fatty acids in the diet has enormous potential for
health improvement. One barrier is that because they are highly unsaturated, they
are easily oxidized, resulting in off flavors and exposure to oxidation products that
have negative health implications. Consuming more oily fish is one way to include
these important fatty acids in the diet. Unfortunately, our food system and choices
do not provide enough fish at a reasonable cost, and many consumers reject regular
fish consumption. We are left with attempts to deliver N-3 fatty acids in formulated
foods, which is a challenge for food technologists. One highly successful approach
has been to add N-3-rich oil to poultry feed so the resulting eggs are rich in N-3 fatty
acids. Technologists have developed several approaches to microencapsulation to
deliver the N-3 oils in foods. Although expensive, the technology shows great prom-
ise for a new generation of healthier functional foods. Additional protection with
antioxidants is also essential.
a
n t i o x i D a n t s
Antioxidants represent a broad group of compounds that stretch across several chem-
ical classes of compounds found in foods and in traditional medicines. Oxidation of
lipids in foods results in off flavors . If high levels of these oxidized materials are con-
sumed over an extended period of time, they can be detrimental to health. Typically,
oxidized foods have strong off flavors and are rejected. Examples of oxidation in
foods in which off flavor occurs are in fish, which develops strong off flavors from
the oxidation of the lipids. Another example is “warmed over” flavor in turkey. When
cooked turkey is reheated, an off flavor is observed. In this case, many consum-
ers either do not recognize the off flavor, and some actually prefer it. Crackers are
another class of food that can develop rancid or oxidized off flavors. This flavor typi-
cally occurs when crackers sprayed with oils rich in unsaturated fats are stored too
long, and the lipids become oxidized. Essentially, lipid oxidation proceeds through a
chain reaction and continues until the chain is broken by an antioxidant. There is an
increasing body of literature demonstrating that the breakdown products from lipid
oxidation are detrimental and are correlated with conditions such as atherosclerosis
(Kubow, 1993; Jessup et al., 2004).
Addition of antioxidants to foods prevents lipid oxidation or breaks the oxidative
chain reaction before the food becomes inedible. Typically, vitamin E or C is used as
a common antioxidant in foods. Other antioxidants are also available for foods, such
as the synthetic phenolic antioxidants BHA and BHT. In recent years, there has been
