Quality evaluation of improved and traditionally dried Bombay duck (Harpodon nehereus) through biochemical, microbiological, and organoleptic analysis

Abstract

The study was conducted to compare the quality and shelf life of traditionally dried (collected from the local markets) Bombay duck (Harpodon nehereus) with improved dried products (produced using a newly developed fish dryer) to assess its suitability. The quality of these products was evaluated through organoleptic, water reconstitution, nutritional, chemical, and microbiological characteristics. The organoleptic quality of improved dried fish was excellent while those produced traditionally were with grayish and dark brown color, rancid odor, and soft and fragile texture with insect infestation. The water reconstitution properties of the improved dried sample were 75.71% and 89.39% at room temperature and 80 °C, respectively, which were comparatively higher than the traditional dried products. The protein, ash, and contents were significantly higher in improved dried fish products while the lipid and total volatile base nitrogen (TVB-N) content were much lower than those of market-dried samples. The total viable counts (TVC) of bacteria were significantly higher in the traditional products which indicated poor quality. To find out the best storage method, dried fish was kept at three different conditions: in the open air at room temperature, in a sealed pack at room temperature, and a sealed pack at refrigeration temperature (4 °C). The shelf life of the products in different storage conditions was evaluated by estimating their moisture, protein, lipid, ash, TVB-N, and TVC values. The products kept at 4 °C temperature was found almost unaltered in terms of their nutritional properties after 4-months storage period. Results indicated that the newly developed fish dryer produced high-quality dried fish products with longer shelf life can be expected if the dried fish is stored at 4 °C refrigeration temperature. Our findings will be a valuable tool for the fish processors to ease the fish drying process and its storage that will enable them to commercially supply good quality dried Harpodon nehereus in the market chain at a low-cost.