Preservative effect of ready to disperse bioactive edible coating powder from fi sh protein hydrolysate incorporated with chitosan and active clove oil on tuna fi llets (Thunnus albacares) during chilled storage

Abstract

Developing bioactive edible coatings is an emerging trend to improve nutritional value, food quality, and safety. The present work was undertaken to develop ready to disperse bioactive edible coating (BEC) powder from fi sh protein hydrolysate incorporated with chitosan and clove oil, and to evaluate their preservative effect (10 and 20% level) on tuna fi llets during chilled storage at 4°C. Microbiological, biochemical, and sensory evaluation were carried out during 18 days of storage study. Aerobic plate count of tuna fi llets treated with 10 and 20% BEC solutions showed 5.45±0.007 log cfu g-1 and 5.33±0.009 log cfu g-1, respectively at the end of storage, whereas the control sample reached 9.25±0.004 log cfu g-1. Among the BEC solution treated samples, 20% BEC solution treated sample had the lowest TBARS (Thiobarbituric acid reactive substances) value (1.68±0.04 mg MDA kg-1) followed by 10% BEC solution treated sample (1.93±0.02 mg MDA kg-1) at the end of the storage, while the control sample exceeded the acceptable limit (2.388±0.167248 mg MDA kg-1) on 9th day itself, which gave clear evidence that BEC solutions effectively extended the tuna fi llet’s shelf-life. The overall study revealed that the sample treated with BEC solutions showed an excellent preservative effect on tuna fi llets, which indicates the potential of combined use of these agents in food products.