Release of free amino-acids during ageing in bovine meat.

The amounts of free amino-acids in Longissimus dorsi (LD), Triceps brachii (TB) and Rectus femoris (RF) from 8 Friesian 20-month old bulls were determinated using gas chromatography. The amounts of free amino-acids released during storage from 3 to 14 days post mortem at 4 °C depended on the muscle. Total free hydroxyproline in LD increased from 3% at 3 days to 11% at 14 days post mortem. Free amino-acids seemed to increase more after 10 days than between 3 and 10 days post mortem. The myofibrillar fragmentation index was highly correlated with leucine, isoleucine, threonine and methionine contents in TB and RF. MFI was correlated with hydroxyproline, leucine and isoleucine in LD.