The microbiology of beef from carcass chilling through primal storage to retail steaks

The primary objective of this study was to investigate if alternative time-temperature carcass chilling combinations resulted in lower microbial (TVC, Enterobacteriaceae, Lactic Acid Bacteria, Pseudomonas spp. And Brochothrix thermosphacta) counts and, if achieved, would reduced levels remain throughout the beef chain. Physicochemical (temperature, pH, water activity) characteristics were also recorded. A secondary objective was to investigate the effect of primal maturation periods (2 versus 5 weeks) on the sensory properties of steaks by a trained panel for colour, odour, tenderness, and flavour. While microbial populations reduced by over 1 log₁₀ ​cfu/cm² by fast carcass chilling, these reductions were lost due to cross contamination in the boning hall and cutting room. The pH and water activity remained stable throughout the study and there was no significant difference for colour or sensory characteristics in retail steaks from the different treatment groups. It was concluded that there was no improvement to the microbial shelf-life of retail steaks from modified chilled carcasses or in the sensory shelf-life of primals which were aged for an extended period.