Preservation effect of protein hydrolysate of rainbow trout roe with a composite coating on the quality of fresh meat during storage at 4 ± 1 °C

Using alcalase and pepsin enzymes, rainbow trout roe protein hydrolysate (RPH) was prepared and its effect along with alginate-chia seed composite coating (CC) was investigated in order to increase the shelf life of meat fillets during refrigeration. As a result of RPH tests, alcalase enzyme produced a RPH with a higher degree of hydrolysis, antioxidant activity, and essential amino acid content. As a result, it was used for further experiments. Afterward, five meat fillet treatments were prepared, T1: control, T2: CC, T3: CC + RPH 1%, T4: CC + RPH 1.5% and T5: CC + BHA, and periodically evaluated for physicochemical (peroxide value, thiobarbituric acid, total volatile nitrogen bases, texture hardness, chewability, and water-holding capacity) and microbiological (total bacterial count, psychrotrophic bacteria). The results showed that CC has antioxidant and antimicrobial properties and the addition of RPH increased the proposed properties, and by increasing the concentration, the better results were observed. Thus, T4 delayed significantly the process of microbial spoilage and oxidation and increased the shelf life of the meat. In most cases, it was more effective than T5 (P < 0.05). All in all, the addition of RPH to CC can meet the demand of consumers for meat products free of chemicals.