SPOILAGE BACTERIA AND QUALITY INDEX METHOD SCORE IN REARED GILTHEAD SEABREAM

Abstract

A model to predict the Quality Index Method (QIM) score increase during the storage was set for Sparus aurata. In this regard, 126 specimens were analysed during the storage in ice, enumerating the spoilage bacteria in Iron Agar as well as evaluating the QIM. The growth curves and the observed QIM scores were used to calculate (fitting method) the terms a and b which relate the bacterial growth to the predicted QIM values. The presumptive Pseudomonas better explains the QIM trends; furthermore the model was validated with regard to other QIM curves obtained during a temperature fluctuating storage, introducing into the predictive system the secondary model for Shewanella spp. (Dalgard, 1995) and Rasmussen et al. (2002). In this case, the model produced a good estimation of the observed QIM.

Keywords

• Sparus aurata
• Quality Index Method
• spoilage bacteria
• predictive model.