Enhancing the nutritional and health value of beef lipids and their relationship with meat quality

This paper focusses on dietary approaches to control intramuscular fat deposition to increase beneficial omega-3 polyunsaturated fatty acids (PUFA) and conjugated linoleic acid content, and reduce saturated fatty acids in beef. Trans-fatty acids in beef lipids are considered, along with relationships between lipids in beef and colour shelf-life and sensory attributes. Ruminal lipolysis and biohydrogenation limit the ability to improve beef lipids. Feeding omega-3 rich forage increases linolenic acid and long-chain PUFA in beef lipids, an effect increased by ruminally-protecting lipids. Increasing beef PUFA can alter flavour characteristics and shelf-life. Antioxidants, particularly α-tocopherol, stabilise high concentrations of muscle PUFA; however, additional antioxidants are required. Currently, the concentration of long-chain omega-3 PUFA achieved in beef lipids (except animals fed ruminally-protected lipids) falls below the limit considered by some authorities to be labelled as a source of n-3 PUFA. The mechanisms regulating fatty acid isomer distribution in bovine tissues remain unclear. Further enhancement of beef lipids requires greater understanding of ruminal biohydrogenation.