A QIM-based evaluation of sensory quality of frozen–thawed roundnose grenadier (Coryphaenoides rupestris) and its applications

Abstract

The quality index method (QIM) is widely used for fish sensory assessment, but there are hardly any studies on quality changes in fish that have been previously frozen. A QIM scheme was developed for frozen Roundnose grenadier once thawed and stored at refrigerated temperatures (4 ± 1 °C). Next, this scheme was applied to determine the shelf life and evaluate the influence of frozen storage time on fish quality. The developed QIM scheme includes six descriptors. The quality index (QI) varies from 0 to 13 points. The maximum QI was reached 16 days after thawing. A strong linear correlation between QI and storage time was achieved (r = 0.9896), the least squares regression line being QI = 0.71 · (days after thawing) + 1.51. Using inverse prediction, the shelf life was estimated to be 5 days from the beginning of thawing. Statistical evidence of the negative effect of previous freezing time on the QI was found in a year-long study