Effect of high pressure processing and thermal treatment on quality of hilsa (Tenualosa ilisha) fillets during refrigerated storage

Abstract

Abstract The effect of high pressure processing (250 and 350 MPa for 10 min) and thermal treatment (75 °C for 5 min) on microbiological, physical and biochemical quality of hilsa fillets during refrigeration storage was studied. Thermally treated and the samples at 350 MPa showed higher L* and b* values with lower a* values compared to both control and samples treated at 250 MPa. Trimethylamine nitrogen levels rose over the storage period but did not exceed the critical limit for both pressure and thermally treated samples. High pressure treatments promoted texture improvement and reduced the samples susceptibility to oxidation Pressurization of 350 MPa effectively prevented lipid hydrolysis. The treated samples maintained lower viable counts throughout the storage, thus having better microbial quality than untreated sample. Pressure treatment of 350 MPa was found to be most effective in preserving the quality and extending the shelf life of hilsa fillets for > 25 days compared to 10 days in raw samples. Industrial relevance Hilsa is a high value commodity with persistent demand in seafood market. But it is highly perishable with limited shelf life. High pressure processed hilsa fillets showed better quality attributes (texture, FFA, lipid oxidation) and extended shelf life compared to thermal treatment. Thus, high pressure processing is potentially more suitable processing method than thermal treatment.