Assessment of European cuttlefish (Sepia officinalis, L.) nutritional value and freshness under ice storage using a developed Quality Index Method (QIM) and biochemical methods

Abstract: The aim of this study was to determine the nutritional value of adult commercial cuttlefish, to develop a Quality Index Method (QIM) scheme, and to evaluate the application of some biochemical methods commonly used for freshness assessment of fish under ice storage. Additionally, shelf-life was to be determined based on both QIM and suitable biochemical methods. The nutritional value of the cuttlefish mantle in the first 24h and after 13 days was determined. Captured cuttlefish was composed (g/100g) by 16.60±0.10g protein, 0.09±0.01g fat, 79.55±0.14g moisture and 1.39±0.03g of ash. After 13 days of ice storage, cuttlefish was composed (g/100g) of 11.90±0.28g protein, 0.17±0.09g fat, 87.04±0.13g moisture and 0.52±0.01g of ash. Differences (p <0.001) were found in protein, ash and moisture but not in fat (p >0.05). These results seem to indicate that there is impregnation of the iced water into the mantle tissue promoting protein leaching with the melting ice. TVB-N and TMA-N displayed a similar increasing tendency, peaking beyond EEC regulations proposed maximum between the 9th and 10th days. The developed QIM scheme for cuttlefish was composed of 29 demerit points, divided into 4 attributes and 13 parameters. The calculated quality index (QI) evolved linearly with storage time in ice (QI=2.68×days in ice−0.61, R 2 =0.9866). Storage time could be estimated with an accuracy of±1 day, if five cuttlefish from each sample were included in the QIM assessment. The shelf-life was determined as 8±1 days by both type of methods (QIM and biochemical). However, the suitability of some biochemical methods to assess freshness need to be more thoroughly researched. [Copyright &y& Elsevier]