Purpose: The purpose of this study is to analyze the dominant spoilage flora in several meat product segments.
Methods: We have applied metagenomics to several spoiled samples of vacuum packaged cooked meat, vacuum packaged fresh meat and vacuum and MAP packaged minced meat as well as roast beef. The V1-V4 region of the 16S rDNA gene was amplified, and high throughput sequencing was conducted with the Illumina Myseq. Typically 2000-3000 reads per sample were obtained.
Results: Vacuum packaged hot dogs (3 samples) contained a dominant flora of LAB like L. sakei and Lc. mesenteroides and was consistent with a previously established list of top 5 spoiling bacteria by culture dependent methods. Aerobically packaged hotdogs contained 70% of Brochotrix. Four vacuum packaged fresh beef pieces slaughtered in different countries and a piece of lamb meat, were invariably dominated by only L. piscium and Lc. inhae, not found in cooked meat. Both species contributed to 70% or more of the total flora. In the case of minced beef, the type of packaging seemed some but limited importance. This may be because the minced meat samples showed high bacterial counts from the start. Apart from four different species of LAB present above 10% in different samples, many samples contained at least 20% of Photobacteria and occasionally up to 70%, making it an important spoiler of minced beef.
Significance: A better understanding of the dominant spoilage flora will lead to better and specific interventions to elongate shelf life.