Quality characterization of farmed Atlantic halibut during ice storage

Summary

A quality index method (QIM) was developed for farmed Atlantic halibut, and together with instrumental, chemical, sensory, and bacteriological analysis, quality changes of halibut stored on ice for 26 d was evaluated. Two groups of fish were fed diets that differed only in the source of lipid, where 1 diet contained only marine oil sources and the other a 50/50 mixture of marine and soybean oil. Fish were slaughtered after 1 y and then stored on ice for 26 d. The fish were sampled on day 1, day 2, and every 2nd day after that. Dietary lipid sources had no effect on freshness, (ATP) degradation (K-value), texture, color, or liquid-holding capacity. The QIM scores increased with storage time, in particular the appearance and eyes parameters. The QIM is a good freshness indicator for halibut. The K-value was strongly correlated with storage time (r = 0.99), while total bacterial counts increased after 7 to 8 d of ice storage. The texture, liquid-holding capacity, and color were significantly affected by storage time during the early period of storage, probably due to rigor stiffness and rigor resolution. The texture, liquid-holding capacity, and color did not change significantly from approximately day 8 of storage until the end of the experiment at day 26.