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Aims:  To evaluate some physiological characteristics of the Enterobacteriaceae isolated from Pecorino cheese. Methods and Results:  The production of organic acids, secondary volatile compounds, biogenic amines (BA) and the lipolytic and proteolytic activities of Citrobacter braakii, Enterobacter sakazakii, Escherichia coli, Kluyvera spp., Salmonella enterica ssp. arizonae and Serratia odorifera strains were determined in skim milk after 48 h of fermentation at 30°C. The proteolytic activity observed only in Ser. odorifera and Kluyvera spp. was confirmed by the peptide profiles of the pH 4·6‐insoluble fraction using RP‐HPLC; however, the lipase activity was evidenced in all the isolates of E. coli, Kluyvera spp. and Salm. enterica ssp. arizonae. During fermentation, all the strains utilized citric acid and produced significant quantities of putrescine followed by histamine, spermine and spermidine as well as acetic and lactic acid. Moreover, the major volatile compounds produced were ethanol, 2,3‐butanedione, 3‐hydroxy‐2‐butanone, 2‐heptanone and acetone. Conclusions:  The Enterobacteriaceae of dairy origin possess many metabolic activities that could affect the sensory quality of the cheese in which they grow during ripening. Significance and Impact of the Study:  The important physiological characteristics possessed by Enterobacteriaceae confirm the complexity of the microbiota of Pecorino Abruzzese cheese, which influences the typical sensory properties of this product.

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The occurrence of biogenic amines in fish is directly associated with microorganisms with decarboxylase activity. These compounds are generally detoxified by oxidases in the intestinal tract of humans, but some conditions, such as alcohol consumption, enzyme deficiency, or monoamino-oxidase antidepressant use, can make their intake by food dangerous. Due to its toxicity, histamine is a unique biogenic amine with regulatory limits for fishery products. This review focuses on biogenic amines in fish, with a detailed picture of the number of alert notifications or intoxication events reported in the last years. The favoring conditions for their formation, as well as the main preventive and control measures to ensure public health, are also reviewed.

VOCs produced by Bacillus from cooked food can be considered as promising antifungal compounds useful in the control of fungal plant pathogens. This study investigates for the first time the correlation between mycelia inhibition of M. perniciosa and F. oxysporum f. sp. lactucae and the VOCs emitted by the Bacillus species.

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