Title: Development of a Quality Index Method (QIM) scheme for farmed Senegalese sole (Solea senegalensis) and its application in a shelf life study.

Temperature is one of the most important factors determining the shelf life of fish. Sensory evaluation is the most important method to assess the freshness quality of seafood. The Quality Index Method (QIM) is a sensory method that can be applied to evaluate fish freshness. The objective of the project was to develop QIM for Senegalese sole and to study the influence of temperature abuse on the freshness and quality of Senegalese sole in a shelf life study. During the shelf life study, one group of fresh farmed Senegalese sole was stored in ice for 16 days (Control group) and a second group was stored at room temperature (20°C) for 16 hours followed by iced storage up to 16 days (T-abused group). Quality changes during storage were observed with sensory evaluation using the Quality Index Method (QIM), Torry freshness scoresheet for cooked fatty fish, chemical and microbial analysis of total viable counts (TVC), hydrogen sulfide (H2S) producing bacteria, and total volatile basic nitrogen (TVB-N). The QIM developed for whole fresh Senegalese sole consisted of 10 quality parameters, and different freshness categories, resulting in a total of 26 demerit points. A high correlation between QI and storage time in ice was observed (R2 = 0,9816). A shelf life of 12-16 days was observed for both groups (Control and T-abused), based on sensory evaluation of cooked Senegalese sole. After 16 days of storage, Total viable microbial counts had reached 7 log10 cfu/g in both groups. The H2S – producing bacteria values were higher in T-abused group, 6 log10 cfu/g compared to 5 log 10 cfu/g in the Control group. Low levels of TVB-N were found during the storage time, ranging between 16.3 and 18.05 mgN/100g.