The impact of ultrasound treatment on glycolytic enzymes when applied to crude extracts from early post-mortem bovine muscle

The rate of pH decline post - mortem and its interaction with temperature influences the final tenderness of meat, and therefore, the manipulation of the rate of pH decline is a strategy of interest in order to obtain consistent high quality meat. Ultrasound is a potential early post - mortem carcass intervention, which may alter the rate of glycolysis based on its ability to alter enzyme activity. In this study, homogenates (prepared from early post-mortem Longissimus thoracis et lumborum muscle) were subjected to different ultrasound intensities (0 %/60 %/100 % amp) and treatment durations (15/ 30 min). The effect of these treatments on the inherent activity of the glycolytic enzymes was investigated using an in vitro glycolytic buffer model system. It was found that ultrasound treatment intensity and duration had a significant interactive effect on the rate of pH decline, and on reducing sugars and lactic acid concentrations, specifically following the 100 % amp ultrasound for 30 min treatment and between 30 and 240 min incubation. No significant differences in pH or metabolites content were observed between treatments after 1440 min of incubation. No effect of ultrasound intensity or treatment duration was observed on the degradation of glycogen. Under the reported conditions of this trial, it can be concluded that the application of ultrasound has limited potential to have an impact on the glycolytic pathways in bovine muscle.