APPLICATION OF METABOLOMICS TECHNIQUE TO DETERMINE METABOLITE PROFILES IN DARK-CUTTING BEEF LONGISSIMUS AND PSOAS MUSCLES

The visual perception of meat color results from incident light properties. A greater-than-normal pH (5.6) can influence both muscle structural and biochemical properties. More specifically, a greater than normal pH promotes muscle fibers to hold water, leading to less reflectance and more absorption. In postmortem muscle, mitochondria remain active and influence meat color by oxygen consumption via utilization of tricarboxylic acid (TCA) cycle- and glycolytic-substrates/metabolites (Tang et al., 2005). In dark-cutting conditions, a greater than normal pH favors mitochondrial respiration. Dark-cutting beef has a greater mitochondrial number and oxygen consumption than normal-pH muscles (Ramanathan et al., 2020). The important role played by metabolites in meat color development has been well characterized. Previous research noted that dark-cutting and normal-pH longissimus lumborum muscles have different metabolite profiles (Ramanathan et al., 2020). Meat discoloration is muscle-specific. For example, muscles predominant in Type I fibers are oxidative in nature and discolor faster than muscle predominant in glycolytic fiber types (Ke et al., 2017). Metabolite profiles of longissimus and psoas muscles are different in normal-pH muscles (Abraham et al., 2017). However, no information is currently available on the metabolite profile differences between longissimus and psoas muscles from dark-cutting beef. The specific goals are:Determine color and biochemical properties of longissimus and psoas muscles from dark-cutting carcasses.Characterize metabolite profiles using non-targeted gas chromatography-based mass spectrometry.