Optimization of restructured seabass and determination of quality changes during frozen storage

In this study, fish meat was restructured and optimized in accordance with the parameters of MTGase, pressure weights and setting time. The most successful restructured fish meat product was reproduced and quality changes were followed during frozen storage. The European sea bass (Dicentrarchus labrax, Linnaeus, 1758) was used as the research material. In the first part of study, fish meats were cut into small pieces and restructured according to Response Surface Method by using MTGase (0%, 0.16%, 0.32%), pressure weights (0 gf/cm2, 2.54 gf/cm2 and 5.09 gf/cm2), setting time (4, 14, 24 hours). Dripping loss, total free amino acid value, hardness value, pH, microbiological load, water activity, microstructure, changes during heat treatment-cooking yield, sensory analysis, deviation in sample size and pore size analyzes were performed to determine the quality of the samples. In line with the selected parameters, it is aimed to reach the product with the lowest dripping loss and total free amino acid content and with a hardness value between 850±30 N. According to all analyzes, samples without MTGase and pressure weights had inefficient results (S1: 4H-2.54 gf/cm2-%0, S5: 14H-0 gf/cm2-%0, S6: 14H- 5.09 gf/cm2-%0, S12: 24 H-2.54 gf/cm2-%0). However good values observed for MTGase and pressure weight combination (S3: 4H-5.09 gf/cm2-0.16%, S4: 4H-2.54 gf/cm2-0.32%, S7 = S8 = S9: 14H-2.54 gf/cm2-0.16%, S11: 14H-5.09 gf/cm2-0.32%, S14: 24H-5.09 gf/cm2-0.16%, S15: 24H-2.54 gf/cm2-0.32%). In addition, it was observed that samples with a configuration time of 14-24 hours came to the fore. These data were also supported by scanning electron microscopy and sensory analysis. In the second part of the study, the optimum product (S16: 17.5H-3.56 gf/cm2-0.32%) was determined and the production was carried out and the quality changes (dripping loss, total free amino acid value, texture profile, pH, TVB-N, totox value, color change, changes during heat treatment, microstructure, sensory analysis, size deviation, pore amount, water activity) were determined during frozen storage (-18°C) for 5 months. In the study, pH and TVB-N levels increased during storage and at the end of the period the totox value was determined below the acceptable limit of 19.5 meq/kg. Dimensional deviation, amount of pores, dripping loss and total free amino acid values were determined at low levels in the products whose texture was tightened by the effect of MTGase and suppression weight. The hardness value was determined between the targeted "850±30N", which reflected positively on the sensory analysis and microstructure results. A decrease in color values had been detected during the storage period. As a result of the productions carried out by the Response Surface Method, it is supported by other analyzes that the optimum production can be made with S16: 17.5H-3.56 gf/cm2-0.32%. Quality analysis shows that the restructured optimum product maintains its quality for 5 months.