Effect of Natural Preservatives on Protein Degradation, Microbiological and Chemical Alterations in Rainbow Trout Fillets

The effects of turmeric (Curcuma longa), quinoa (Chenopodium quinoa), cardamom (Elettaria cardamomum), and chitosan coatings on the rainbow trout fillets were evaluated based on the protein profile, bacterial content (total aerobic mesophilic, psychotropic and lactic acid bacteria, Pseudomonas and Enterobacteriaceae), lipid peroxidation (TBARS), total volatile basic nitrogen (TVB-N) and pH values on quality during 12 days. The decrease in bacterial growth activity, physicochemical values (TVB-N, TBARS and pH) and prolonged shelf life in a natural preservative dependence were observed in the fillets. Generally all the test parameters, such as microbiological, physicochemical as well as the lowest mean values were identified in the coatings of the fillets with turmeric and cardamom (p<0.05). Control and quinoa groups resulted in increased number of bacteria and chemical values compared to other treatment groups (p<0.05). The turmeric coating also results in increased protein concentration compared to other coatings and control group (p<0.05).