Altered post-mortem metabolism identified in very fast chilled lamb M. longissimus thoracis et lumborum using metabolomic analysis

Metabolite Profile Differences between Beef Longissimus and Psoas Muscles during Display

“…The application of metabolomics has been applied in diverse research areas such as human medicine, drug discovery, plant science, human nutrition, and food science (Kaddurah-Daouk and Krishnan, 2008;Wishart, 2008;Cevallos-Cevallos et al, 2009). Few studies have utilized metabolomics techniques to characterize the role of metabolites in meat tenderness and water-holding capacity (Bertram et al, 2010;Graham et al, 2010;D´Alessandro et al, 2011;Warner et al, 2015).…”

Very fast chilling modifies the structure of muscle fibres in hot-boned beef loin

“…Bendall (1973) reported that a slower rate of fall in pH occurs during the early stages of post-mortem metabolism when ATP is being resynthesised from creatine phosphate, and a noticeable increase in the rate of pH fall when resynthesis through this mechanism failed. Changes in metabolism occurred within 1.5 and 5.5 h postmortem with VFC, with higher levels of glycolytic intermediate metabolites being measured (Warner et al, 2015); therefore the effects of VFC on pH decline, Ca 2+ flux and metabolism warrants further investigation.…”

“…Several mechanisms have been suggested for the tenderisation of meat as a direct result of VFC applied to pre-rigor meat, including; prevention of sarcomere shortening by physical restraint provided by a hard crust on the outer surface, accelerated protease activity due to early release of calcium from the sarcoplasmic reticulum (SR) (Davey & Garnett, 1980;Jaime et al, 1992;Joseph, 1996), and rapid metabolism interfering with the actomyosin rigor bond (Warner et al, 2015). Sheridan (1990) showed that VFC resulted in a fast glycolysis rate that led to a rapid pH decline, while Roncales (1998) hypothesised that VFC caused physical damage to the myofibrillar structure resulting in increased tenderness.…”

“…showed that sarcomere shortening is prevented independently of external restraint when temperature and time specifications were optimised for VFC. Warner et al (2015) suggested that the increased production of inosine 5-monophosphate (IMP) in VFC muscle caused a weakening of the actin-myosin bridge, affecting the tenderness. In spite of these suggested hypotheses, the mechanism of tenderisation involved when using VFC is still not fully understood, although it is unlikely to be due to acceleration of the protease activity seen with conventional chilling.…”

“…One hypothesis proposed by Warner et al (2015), is that IMP is in higher concentration in pre-rigor VFC muscle, so may substitute for ATP on the myosin head and allow the myosin head to dissociate from actin, thus breaking the cross-bridge. Bendall (1973) reported that a slower rate of fall in pH occurs during the early stages of post-mortem metabolism when ATP is being resynthesised from creatine phosphate, and a noticeable increase in the rate of pH fall when resynthesis through this mechanism failed.…”