Analysis of the Physico-Chemical Characteristics and Content of Selected Bioactive Components in Lamb Meat, Depending on the Type of Muscle and Vacuum Aging Time

The impact of processes related to meat aging on physico-chemical characteristics and biologically active compound content remain in the minority. Thus, the aim of the study was to analyze the physico-chemical traits (pH, meat color, expressed juice, moisture content, protein, fat, total collagen, and fatty acids) and carnosine, taurine, and L-carnitine content for fresh meat and vacuum-packaged meat aged for 7 and 14 days at temperature of 2°C, from the longissimus lumborum (LL) and gluteus medius (GM) muscles. This was carried out using 66 Polish Merino heavy lambs. In both muscles, the L* parameter decreased in aged meat, however, the differences with respect to fresh meat were not statistically confirmed. In the gluteus medius muscle, a higher (P<0.05) redness value (a*) and lower yellowness (b*) were recorded in meat after aging. A lower (P<0.05) expressed juice value was found in both LL and GM after 7 days of aging. An increase (P<0.05) in protein and fat content in both muscles, and collagen content in LL was observed in aging meat. There was no difference in fatty acid groups or C18:2 c9, t11 content between the GM and LL muscles, or fresh and aging meat. A higher TBARS (thiobarbituric acid reactive substances) content (P<0.05) was recorded in meat after aging for both GM and LL. The meat aging process increased (P<0.05) the carnitine and taurine content, while the carnosine content decreased. Apart from carnosine, the aging process did not significantly reduce the content of bioactive ingredients, which are important in the human diet. This process also did not negatively affect the physico-chemical characteristics determining consumers’ evaluation of the meat.