The aim of this thesis is to determine the oxidative stability of proteins (formation of carbonyls), lipids and colour of vacuum packed lamb and veal at a constant temperature of 2 °C ± 1 °C up to 15 days or 21 days. The suitability of veal and lamb loin (longissimus lumborum) for ageing and optimal ageing time to achieve optimum sensory properties, tenderness and aroma has been determined. A sample of 100 g of lamb meat contains 23.48 g of protein, 69.66 g of water and 5.48 g of fat. Lamb samples were the most tender after 11 days (both the sensory assessed property and the instrumentally measured share force that decreased by 61%) and the best aroma after 15 days of ageing. In the meantime, the lamb became significantly brighter and more saturated (higher L*, a* and b* values), the content of secondary lipid oxidation products increased (1.7 times higher amount of malondialdehyde), and the content of protein carbonyls decreased to the initial value, despite an initial increase after 7 days of ageing. A sample of 100 g veal contains 22.47 g of protein, 70.27 g of water and 5.32 g of fat. Veal samples were the most tender (both the sensory assessed property and the instrumentally measured share force that decreased by 33%), juiciest and best in odour and aroma after 21 days of ageing. During this period, the colour did not change significantly (except for an increase in the b* value), nor did the amount of oxidation products of the lipids change, but the protein carbonyl content increased (after 14 days of ageing). For a realistic evaluation of the protein oxidation rate in lamb and veal, it should be noted that a 7-day freezing of the sample before analysis significantly reduces the protein carbonyl content (32%) We found that lamb and veal loins with loin are suitable pieces for maturation; the optimal ageing time is 15 days for lamb and 21 days for veal.
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