Effect of sex and sub-zero storage temperature on the microbial and oxidative stability of beef packed in a high-oxygen atmosphere after different vacuum ageing times

This study aimed to evaluate the effect of sex and sub-zero storage temperature on the microbial and oxidative stability of Belgian Blue beef packed in a high-oxygen atmosphere after different ageing times. Longissimus thoracis et lumborum from Belgian Blue young bulls and cull cows were aged at -1 or 4 degrees C for 80 days in vacuum. Every 20 days, samples were repackaged in a high-oxygen atmosphere (70/30% O-2/CO2) and stored for 7 days (2 days at 4 degrees C + 5 days at 8 degrees C). Ageing at -1 degrees C had a protective effect against the growth of lactic acid bacteria and Enterobacteriaceae and myoglobin oxidation. Brochothrix thermosphacta was the limiting parameter for ageing longer than 20 days at -1 degrees C, permitting a subsequent 7-day shelf-life in a high-oxygen atmosphere. Meat from young bulls was more sensitive to oxidation than meat from cull cows. Extending Belgian Blue meat ageing for > 20 days had a negative impact on retail shelf-life.