Conservation and quality of grumatã (Prochilodus lineatus) fillets after different depuration periods and frozen storage

Abstract

The aim of this study was to evaluate the physicochemical, microbiological, sensory and meat quality characteristics of grumatã fillets after different depuration (0, 48, 72 and 96 h) periods and frozen storage (0, 2, 4 and 6 months). The fish collected in a dam were distributed in tanks at a density of 3.8 kg m^{3 -1}. After depuration periods all fish were filleted and the fillet samples were stored (-18°C) until analyzing. Lower fat content was found in fish submitted to depuration for 48 and 96 h compared to those non-depurated and depurated for 72 h. Muscle protein was preserved in all the fish depurated. Sensory analysis showed no significant differences in appearance, color, texture and flavor attributes and overall acceptance. During the frozen storage, pH, Total Volatile Basic Nitrogen (TVB-N), peroxide and Thiobarbituric Acid Reactive Substance (TBARS) values were evaluated in the fillet samples, every two months. The pH values increased up to four months of storage. The TVB-N values ranged in fillets from fish depurated for 48 and 96 h. Peroxide values increased from the fourth month of storage and in the sixth month, the highest values were observed. For TBARS values, increased values were found in fillets from non-depurated fish and lower values in other depuration periods. Thus, depuration proves to be more efficient to maintain the quality of grumatã fillets at frozen storage.