Microbiota on vacuum-packaged chilled beef steaks inoculated with a Carnobacterium maltaromaticum strain

A Carnobacterium maltaromaticum strain, A5, was associated with a very long storage life of vacuum packaged beef and was able to inhibit the growth of multiple strains of spoilage associated and pathogenic bacteria that are of importance to beef under lab conditions. The present study investigated whether the inhibitory effect of this strain at very low numbers can be reproduced in vivo, i.e. on chilled vacuum packaged beef. C. maltaromaticum A5 up to 2 log CFU per cm2 was spiked onto beef steaks. The steaks were vacuum packaged and stored at 2oC for up to 12 weeks. The dynamics of the microbiota were determined by both conventional plating and 16S rRNA gene amplicon sequencing methods. The predominant bacterial species at the end of storage were determined using both whole metagenome sequencing and whole genome sequencing.