The Microbiome Characterization of Edible Visceral Organs and Fresh Meat During Production in a Pig Processing Facility in Thailand

Besides meat, pig organs are traditionally consumed in Asia. However, they can be a source of food poisoning. Less is known about the microbiome associated with different organ meats and the inter-animal variation in the microbiomes of organs. The aim of this pilot study was to characterize and compare the bacterial composition in fresh pig meat and organs (i.e., tonsils, lungs, and spleen) and blood from several carcasses using 16S rRNA amplicon sequencing as a screening method. We also investigated how closely the bacterial composition of the meat and organ samples was related to the gut bacterial community and the bacterial communities on the hands of the workers at different positions during meat processing. Meat, organ, blood, and gut (cecum and feces) samples were collected from 12 carcasses in two batches (<i>n</i> = 6/batch), along with swab samples (<i>n</i> = 4/batch) from the hands of the workers at different positions along the processing chain, from which DNA was extracted. The results for the bacterial diversity showed that each sample type (meat, organ, and blood) comprised a unique taxonomic composition (<i>p</i> < 0.05). Moreover, the data confirmed great inter-animal and batch variation for the meat, organs, and blood, which is helpful information for implementing strategies to enhance hygiene measures at pig farms and slaughterhouses, and hence food safety and quality. The genera associated with food safety and spoilage, such as <i>Anoxybacillus</i>, <i>Acinetobacter</i>, <i>Pseudomonas</i>, <i>Campylobacter</i>, and <i>Streptococcus</i>, were also different between the meat, organs, and blood. The bacterial communities in the gut samples distinctly clustered from communities in the pig organs and meat, whereas some overlaps in community clusters between lung, meat, and hand samples existed. This study demonstrates that the spleen, tonsils, and lungs contained more bacterial genera that comprise pathogenic strains than meat cuts, supporting the need to monitor their microbiome composition as potential contamination sources for food safety and spoilage reasons.