The impact of salt concentrations on the physicochemical and microbiological changes of rainbow trout caviar

Abstract

Fish and other fishery products are among the foods recommended for the prevention and treatment of diseases with their high nutritional properties. The demand for fish caviar has increased in recent years due to the increase in fish consumption and their high nutritional and commercial value. In order to meet this increasing demand, caviar substitutes obtained from different fish species have been investigated, however in these limited studies, generally, information about products and markets are provided. In this study, caviar obtained from 30 female rainbow trout (Oncorhynchus mykiss, raised under farm conditions) were processed with different salt concentrations (2, 4 and 8%). Physicochemical [lipid peroxidation (with Thiobarbituric Acid Reactive Substance (TBARS), protein degradation (with Sodium Dodecyl Sulfate - PolyAcrylamide Gel Electrophoresis (SDS-PAGE), color (L*, a*, b*) and salt content of caviar formed by salting process)] and microbiological [total aerobic bacteria (TAB)] quality parameters on certain days of 21-day storage (4 °C) (0., 3., 6., 9., 12., 15., 18., and 21.) was investigated. As a result of the study, the changes in TAB, TBARS, L *, a *, b * values and salinity levels during storage were determined as important (p < 0.05). At the end of storage, it was detected in different profiles as well as phosphoprotein and glycoproteins as major protein groups in the SDS-PAGE analysis. In terms of microbiology, 8% salt concentration was found to be very low compared to control and other salt applications. Considering all the research findings, high salt concentrations were determined to have a positive effect on the preservation of quality.