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Aims: To relate sensory shelf-life of iced whole and gutted squid to bacterial growth and chemical changes. Methods and Results: Cooked mantles from whole and gutted individuals were rejected after 10 and 12 days of storage, respectively, due to ammoniacal off-odours. Rate of production of both ammonia and trimethylamine was highest in the whole lot. Agmatine, which was only present in trace amounts in freshly-caught squid, increased rapidly in both lots. The main microflora at the time of sensory rejection of iced whole squid included Gram-negative, motile and non-fermentative rods, which were psychrophilic and had a requirement for NaCl. 16S rDNA sequence analyses identified the strains as belonging to the genus Pseudoalteromonas . Shewanella putrefaciens , Pseudoalteromonas sp. and Pseudomonas sp. dominated in spoiled gutted squid. Identification of strains from the stomach and digestive gland of recently-captured squid showed that the main flora consisted of Photobacterium phosphoreum. Conclusions: Spoilage of iced squid is likely to result from a combination of autolytic and bacterial changes. Agmatine seems to be an excellent freshness indicator. Photobacterium phosphoreum may contribute to spoilage through activity in the digestive gland, followed by diffusion of volatile compounds and amines to the mantle. Significance and Impact of the Study: Due to the psychrophilic nature of P. phosphoreum and Pseudoalteromonas sp., spread-plating and low temperature incubation are recommended for bacteriological evaluation of iced squid. [ABSTRACT FROM AUTHOR]

The microbiological and physico-chemical characteristics of dry-cured Spanish "serrano" hams with deep spoilage were compared to unspoiled hams, and the evolution of similar characteristics was studied during the early curing stages of previously refrigerated or frozen hams. The results suggest a relationship between deep spoilage and the presence of Enterobacteriaceae, caused by insufficient NaCl concentrations during curing. Strains of Serratia liquefaciens, Enterobacter cloacae and Proteus vulgaris, which comprised the most frequently isolated species of enterobacteria from spoiled hams, were therefore characterised in a model system in order to examine their ability to grow in different NaCl concentrations at different temperatures. Strains isolated from normal hams during early curing stages and from the production environment were included for comparison. The results showed that all strains were able to grow in 7% NaCl at 5 °C, and that strains isolated from spoiled hams did not differ from those isolated from normal hams and from the environment. The NaCl tolerance of strains isolated from spoiled hams was closely linked to incubation temperature, and a reduction in temperature from 5 °C to 2 °C reduced the tolerance significantly. [ABSTRACT FROM AUTHOR]