EXTENSION OF THE CHILLED STORAGE LIFE OF SMOKED BLUE COD (PARAPERCIS-COLIAS) BY CARBON-DIOXIDE PACKAGING

Commercially prepared smoked blue cod (Parapercis colias), packaged ae robically, under vacuum and in carbon dioxide controlled atmosphere pa cks, was stored at +3-degrees-C and -1.5-degrees-C. Product stored aer obically on overwrapped polystyrene trays spoiled by 14 and 28 days re spectively, and that in vacuum packs spoiled by 14 and 35 days respect ively, when held at 3-degrees-C and -1.5-degrees-C. In contrast, produ ct in carbon dioxide packs remained acceptable until the 3-degrees-C a nd -1.5-degrees-C storage trials ended after 49 and 113 days respectiv ely. Microbial spoilage was first evident in overwrapped product store d aerobically and in vacuum-packed product as offensive putrid amine-l ike odours on pack opening. These odours were associated with the deve lopment of a predominantly Gram-negative spoilage microflora. Extensio n of product life afforded by the use of carbon dioxide controlled atm osphere packaging is attributable to a significant extension of the la g phase before spoilage microflora proliferation commenced and to the selection of a low-spoilage-potential lactic-acid-bacteria-dominated f lora. Although the use of carbon dioxide packaging offers an export po tential for chilled smoked blue cod, caution must be advocated until p roduct safety, in respect to the growth of cold tolerant pathogens in the case of temperature abuse (>3-degrees-C), can be more fully evalua ted.