Cis/Trans-Fatty Acid Content of Red Meats and the Related Effects on Meat Quality and Human Health

Red meats are often criticized as unhealthy based on their perceived high-fat content and saturated fatty acid composition. Uncertainties about the fatty acid composition and trans-fatty acid contents may discourage consumers to eat red meat, especially those living with non-communicable diseases such as cardiovascular diseases, hypertension and obesity (e.g. the metabolic syndrome). Previous studies have investigated the factors that influence the fat content and fatty acid composition of red meats, including the effects of species, age, nutrition, sex, production systems and growth promotants in animals, but the trans-fatty acid content of red meat has not been well studied to date. The purpose of this chapter is to review the fat content and fatty acid composition of red meats, with specific reference to its cis/trans-fatty acid content. Representative samples of beef sirloin steaks (n = 60) and lamb loin chops (n = 80) (the lumbar part of the longissimus dorsi muscle) were collected from carcasses from several randomly selected abattoirs in the Gauteng region of South Africa for proximate and fatty acid analyses. Results from this study confirm that the intramuscular fat content of red meats is low compared to most fat-containing processed foods. The lean component of beef and lamb contain a trivial proportion of TFA’s, consisting of vaccenic acid, rumenic acid and conjugated linoleic acid (CLA) isomers. The CLA’s in red meat are beneficial due to their antioxidant and anti-carcinogenic properties, so they should not strictly be considered in the TFA definition. This means that the TFA’s in red meats are negligible and pose no harm to human health. Labelling of red meats should be improved to convey this information to consumers.

Comparison of branded and non-branded food samples widely consumed in north India with reference to Trans fatty acid content

Trans fatty acids (TFA) are the geometrical isomers of monounsaturated and polyunsaturated fatty acids that affect the functional and physicochemical properties of these fatty acids, which in turn affect their metabolism in humans. Since the database available for trans fatty acids in food from India is scarce, the research report generates data about trans fatty acid content in selected foods popular in north India. In this report, various food samples like cookies, chocolates, biscuits, pizza, fries, indigenous snacks like samosa, pakora and indigenous sweets like jalebi, gulab jamun, and laddoo were analyzed for the Trans Fatty Acid (TFA) content by gas chromatography. A large variation was found in trans fatty acid content among these food samples. The results also showed that only 4.5% of the samples were found to contain TFA less than 0.5% while approximately 8% of samples having more than 5% TFA (1 branded and 6 non-branded samples). Also, a large variation was found in the trans fatty acid content of branded and non-branded food samples with the mean value of TFA in branded and non-branded food groups as 1.781 and 6.125 respectively and the t-value of 0.852 between the two groups. When regulations are emphasizing on labelling the TFA content on the product, there are arrays of unlabelled products which are not governed under any regulations. Hence there is a need for strong food regulations to bring levels of trans fats in processed foods to negligible levels.