ABSTRACT
Predictive microbiology has been suggested as a possible alternative to traditional microbiological assessment of food safety and quality. The effect of various environmental factors on growth of microorganisms has since been quantified in laboratory media and kinetic models have been developed. For most fish products the microorganisms responsible for spoilage, however, are not known and the spoilage microflora are also likely to change when storage conditions (e.g. temperature and atmosphere) are changed over wide ranges. This dynamic nature of the microbial spoilage process indicate that the spoilage domains of specific spoilage organisms must be determined before kinetic models can be developed. The present paper shows how quantitative comparisons of results from product and model system experiments have led to the conclusion that Photobacterium phosphoreum is responsible for spoilage of chilled packed cod. A simple model for the effect of CO, on this organism has been developed and found valid for accurate prediction of microbial spoilage. The square root model was found to be appropriate for predicting the effect of temperature on shelf life of superchilled and packed fresh fish and a new empirical model has been developed for the effect of temperature (O°C to 30°C) on the shelf life of fish from warm tropical waters.
