Effect of finishing and ageing time on quality attributes of loin from the meat of Holstein-Fresian cull cows.

The effects of finishing time, (T0=0, T1=30 and T2=60days), on Holstein-Friesian cull cows (n=18) and post-mortem ageing, (1, 7, 14, 21, 35 and 42days), under vacuum conditions of Longissimus thoracis (LT) muscles were investigated. The objective of this research was to study how finishing feeding (based on a commercial concentrate and corn silage), following a pasture period of 90days, affected carcass and meat quality. Ageing time effect was also evaluated on the main quality attribute of added value pieces, such as "striploin of ox" from cull cows. Finishing treatment affected intramuscular fat content (IMF), moisture percentage, water-holding capacity (WHC), colour parameters and shear force of meat at 24h post-mortem, whereas ageing time enhanced meat tenderness, when this was measured by two textural tests, Warner-Braztler (WB) and textural profile analysis (TPA). A minimum shear force was achieved at 7 and 14days of ageing for T1 and T2, respectively. No differences (P>0.05) could be found in colour parameters from 7 to 42days. The results show that a finishing time of two months is very beneficial, due to the increase in meat fatness, improved overall carcass quality and luminosity (L*). Furthermore, 14 ageing days were sufficient to improved tenderness. Ageing time did not have an effect on lipid oxidation (P>0.05) and this leads us to conclude that meat shelf life exceeded 42days under vacuum conditions'.