Packaging conditions for extended storage of chilled dark, firm, dry beef

Bacterial fermentation of meats

“…During storage at 1 oc, vacuum-packaged beef cuts developed spoilage floras of lactobacilli and enterobacteria. Cuts stored under C02 developed floras of lactobacilli alone (Gill and Penney, 1986). LAB capable of producing hydrogen sulphide have been isolated from a variety of vacuum-packaged meats (Shay et al, 1988).…”

“…Leuconostoc mesenteroides appeared to be associated with the deterioration in lean colour of vacuum-packaged beef knuckles (Savell et al, 1986). Vacuum-packaged high pH meat will usually be spoiled relatively rapidly by the activities of enterobacteria and associated pH-sensitive facultative anaerobes such as Alteromonas putrefaciens and Brochothrix thermosphacta (Gill and Penney, 1986). Maximum viable numbers on vacuum-packaged meat are typically below 10 8 /cm 2 and remain at this level for several weeks.…”

Microbiological, physical and chemical studies on fresh red meats packaged under different modified gas atmospheres

“…found that in aerobic systems, such as those used for display packs, increasing the CO2 concentration beyond 20 to 30%C02 had little additional inhibitory effect on Pseudomonas-6om\na\eô spoilage flora. On the other hand, in anaerobic systems used to extend the storage life before meat is prepared for display, Gill and Penny (1986) recommended that atmospheres of 100%C02 may be used, as the inhibitory effects of CO2 on both lactobacilli and Enterobacteriaceae components of anoxic floras increase with increasing CO2 concentration. The effect of CO2 on spoilage bacteria differs with the medium.…”

“…Gill (1988b) reported that when CO2 was added in excess of that required to saturate the meat at atmospheric pressure, growth of lactobacilli, the predominant organisms in the spoilage flora of anoxically packaged meat, was retarded. The same condition also imposed an extensive lag on enterobacteria that ultimately caused putrid spoilage of high-pH red meats in CO2 packaging ; and could extend the storage life of chilled red meat over 24 weeks (Gill, 1986).…”

“…High concentrations of CO2 may discolor meat or denature certain meat proteins (Clark and Lentz, 1969;Gill, 1986); low levels of O2 also accelerate the formation of brown metmyoglobin , while high levels of O2 may catalyze oxidative rancidity (Watts, 1954). Therefore, the second objective of this project was to determine the effect of different ratios of CO2 and O2 on the physical and chemical properties such as color, purge loss and fat oxidation in fresh pork.…”