Aging is a popular method used by meat industry for improving the sensory attributes of meat. Despite the advent of many novel technologies, aging has not lost its charm and is still widely used commercially as a post-mortem intervention for tenderization. Aging improves the tenderness of meat through disruption of the muscle structure by intracellular proteolytic systems. Muscles undergo various molecular changes that cause proteolysis of key myofibrillar and cytoskeletal proteins, disrupting the overall integrity of muscle cells. Although several endogenous proteolytic systems are capable of post-mortem proteolysis, a great body of scientific evidence supports a major role for the calpain system. Calpains are intracellular calcium-dependent cysteine proteases found in most eukaryotes. At least three calpains (μ- and m-calpains and calpain 3) and calpastatin, their specific endogenous inhibitor, are found in muscle. They are known to be involved in the proteolysis of functionally relevant structural proteins such as the myofibrillar proteins and cytoskeletal anchorage complexes. These ubiquitous proteases are also present in mitochondria and play important roles in a variety of pathophysiological conditions including apoptotic and necrotic cell death phenomena. This review discusses the role and contribution of the calpain system and the factors that influence calpain activity during aging.

The study was conducted to explore the possibility of utilization of Terminalia arjuna as a novel natural preservative in meat products by using chevon sausages as a model system. Chevon sausages were prepared by incorporating different levels of T. arjuna viz. T₁ (0.25%), T₂ (0.50%) and T₃ (0.75%) and were assessed for various lipid oxidative stability and storage quality parameters under refrigerated (4 ± 1 °C) conditions. T. arjuna showed a significant (p<0.05) effect on the lipid oxidative stability as the treated products exhibited significantly (p<0.05) lower TBARS (mg malonaldehyde/kg) values in comparison to control. A significant (p<0.05) effect was also observed on the microbial stability as T. arjuna incorporated products showed significantly (p<0.05) lower values for total plate count (log cfu/g), psychrophilic count (log cfu/g), yeast and mould count (log cfu/g) and FFA (% oleic acid) values. Significantly (p<0.05) higher scores were observed for various sensory parameters of the products incorporated with T. arjuna during refrigerated storage. T. arjuna successfully improved the lipid oxidative stability and storage quality of the model meat product and may be commercially exploited as a novel preservative in muscle foods.