Impacts of hanging method and high pre-rigor temperature and duration on quality attributes of ovine muscles

Abstract

This study evaluated effects of high pre-rigor temperature and duration and suspension of lamb sides on quality traits and protein denaturation in two muscles [semimembranosus (SM) and longissimus thoracis et lumborum (LTL)]. Twenty-four lamb carcasses, within each of 3 slaughter days, were used to assign eight carcasses to one of four pre-rigor temperature treatments: chilled at 2°C directly after slaughter, or held at 37°C in water for 1.5, 3.0 or 4.5 h before transfer to a 2°C chiller. At ~15 min post slaughter, one side of each carcass was suspended from the Achilles tendon, whereas the other side was suspended by the aitch bone and the leg tied down to the ribs. The sides subjected to aitch bone hanging had an increased sarcomere length in the SM, but decreased sarcomere length in the LTL. For the LTL, the time of exposure to high pre-rigor temperature had a significant effect on measures of protein denaturation and related meat quality traits such as purge and colour, although tenderness (shear force) after 2 days of aging was not affected. For the SM, the high temperature treatment also resulted in increase in measures of protein denaturation and thus negatively influenced meat quality traits such as purge, colour and shear force after aging. However, these effects on purge and shear force in the SM were significantly mitigated by the aitchbone hanging treatment. The results of the present experiment indicate that pre-rigor aitchbone hanging of muscles can counteract the negative effects of high pre-rigor temperature on both water loss and meat tenderness.