Extension of Shelf Life of Minced Beef by Storage in Vacuum Packages with Carbon Dioxide

Beef intended for production of mince (ground beef) was vacuum packed in minced and unminced form and in the presence and absence of solid CO₂. Subsequently the meat was displayed using overwrap-type packs to assess its shelf-life as beef mince. The total microbial load was reduced by mincing after storage and this also helped maintain the bloom in overwrap packs. Addition of CO₂ markedly reduced growth of aerobic spoilage organisms during storage and during subsequent display. Lactic acid bacteria were affected less than aerobes but levels of CO₂ above 2 g/kg of meat slowed their growth in the vacuum packages but not in overwrap packs. Overall, CO₂ addition helped maintain the bloom of the meat and reduced total microbial numbers. It thus reduced the adverse effects of storage in vacuum packages and could produce a product more stable, during display, than the fresh meat.