A survey of the microbial communities of commercial pre-sliced, packaged deli-style ham throughout storage

Abstract

The goal of this study was to evaluate the variation in spoilage microbiota associated with sliced, pre-packaged, deli-style ham from varying processing environments available in the retail market in the United States.  Three different brands of pre-sliced ham, water added were purchased at local markets and evaluated every two weeks beginning four weeks prior to the sell-by date until four weeks beyond the sell-by date.  Analysis of 16S rRNA genes using operational taxonomic units (OTUs) showed that brand A had a different bacterial community structure compared to brands B and C, according to unweighted(P = 0.006) and weighted (P < 0.001) UniFrac distance matrices.  Brand A had a greater proportion of sequence reads mapping to Carnobacterium, Bacillus, and Prevotella, while B and C had greater proportions of Pseudomonas, Photobacterium, and Lactococcus.  Brand A also had a lower salt concentration(P < 0.007), greater moisture percentage and less fat percentage (P< 0.012) and increased aerobic plate count (APC) (P = 0.017).  Differences in spoilage microbiota can in part be attributed to the factors involved with different processing locations, as shown by three different brands of ham, as well as slight differences in formulation including salt concentration and organic acid use.