Influence of carcass suspension on meat quality of Charolais heifers from two sustainable feeding regimes

摘要

This study investigated the effects of pelvic suspension on the meat quality of M. longissimus dorsi, M. semimembranosus and M. adductor from 35 heifers with at least 75% Charolais breeding. Two-thirds of the heifers were slaughtered directly from pasture at 18 months of age and one-third was finished indoors and slaughtered at 22 months. After slaughter and electrical stimulation one side of each carcass was re-suspended by either the achilles tendon or the pelvic bone. Longissimus muscles were aged 7 or 14 days and were then evaluated for drip loss, colour, shear force and sensory analysis. As compared to 18-month-old heifers, 22-month-old heifers were heavier, more muscular and fatter (P < 0.05). Intramuscular fat content increased with slaughter age (P < 0.003). Pelvic suspension reduced longissimus peak force values, total energy, pH and thawing losses (P < 0.05) in heifers slaughtered at 18 months. Semimembranosus showed the largest response to pelvic suspension with significantly lower peak force and total energy values. Finishing for 4 months did not affect longissimus shear forces. Achilles-suspended samples had lower shear force values after 14 v. 7 days of ageing. Pelvic-suspended samples aged 7 days were, however, just as tender as those aged 14 days. Sensory analysis of longissimus samples aged 14 days showed that samples from pelvic-suspended sides had higher tenderness, lower bite resistance, more meaty taste and less visible marbling compared with samples from achilles-suspended carcasses.