9In this study, coagulase positive staphylococci (CPS) were detected in 45% of the 69 bovine 10 milk, whey and cheese samples from five farm dairies, and all raw milk samples were 11 contaminated. Genetic diversity, staphylococcal enterotoxin genes and antimicrobial 12 susceptibility in putative Staphylococcus aureus isolates were investigated. Sixty-one percent 13 of the 72 isolates analysed belonged to the same PFGE group. The spa-typing revealed seven 14 different spa types, t2678 being the most prevalent, but t127 and t197 were also detected. 15Sixteen different toxin gene profiles were identified in 87.5% of the isolates with sec and tst 16 being the most frequent (52.5%), followed by seg and seh. All isolates were MSSA 17 (methicillin-sensitive S. aureus), and sensitive to the 12 antibiotics tested. The prevalence of 18 S. aureus, and the high diversity of isolates carrying enterotoxin genes, constitute grounds for 19 food safety concern in artisanal cheese making, whether pasteurized or not.

The experimental design was set up to study the effect of different modified atmospheres (CO2 (67 or 33%) balanced with either O2 or N2) on autolytic-and microbiological deterioration of chilled saithe (Pollachius virens). As controls, vacuum packaged saithe was used. The results showed a positive effect of gas mixtures containing O2 on physiochemical and microbial product quality. Discriminating factors were; lower psychrotrophic count, slower breakdown of ATP, lower contents of certain biogenic amines (e.g. cadaverine) and reduced drip loss during storage. A high CO2 concentration (67%) in the packaging atmosphere was moreover found to inhibit microbial proliferation. Vacuumpackaged saithe stand out negatively with highest DL and reduced sensory shelf life and physiochemical and microbial quality. It was moreover found that increased drip loss, and higher contents of hypoxanthine and cadaverine in the muscle tissue was related to the microbiological ecology (i.e. increased growth of Shewanella spp. and Photobacterium spp.).

Continuous monitoring of antimicrobial resistance in bacteria along the food chain is crucial for the assessment of human health risks. Uncritical use of antibiotics in farming over years can be one of the main reasons for increased antibiotic resistance in bacteria. In this study, we aimed to classify 222 presumptive Pseudomonas isolates originating from a salmon processing environment, and to examine the phenotypic and genotypic antibiotic resistance profiles of these isolates. Of all the analyzed isolates 68% belonged to Pseudomonas, and the most abundant species were Pseudomonas fluorescens, Pseudomonas azotoformans, Pseudomonas gessardii, Pseudomonas libanesis, Pseudomonas lundensis, Pseudomonas cedrina and Pseudomonas extremaustralis based on sequencing of the rpoD gene. As many as 27% of Pseudomonas isolates could not be classified to species level. Phenotypic susceptibility analysis by disc diffusion method revealed a high level of resistance towards the antibiotics ampicillin, amoxicillin, cefotaxime, ceftriaxone, imipenem, and the fish farming relevant antibiotics florfenicol and oxolinic acid among the Pseudomonas isolates. Whole genome sequencing and subsequent analysis of AMR determinants by ResFinder and CARD revealed that no isolates harbored any acquired resistance determinants, but all isolates carried variants of genes known from P. aeruginosa to be involved in multidrug efflux pump systems.

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