Consequence of dippin time in preservative on the quality of smoked silver carp stored at ambient and refrigeration temperature

Abstract

Shamim Anik, Kibria Aurona, Rubel Kazol

The study was conducted to evaluate the effect of dipping time in brine on the shelf-life of hot-smoked Silver carp (Hypophthalmichthys molitrix) stored at ambient (23-26ºC) and refrigeration (4ºC) temperature. The fish in two treatments named A and B were salt-dipped for 15 and 30 minutes respectively in a saturated brine solution (≈25% NaCl). The fish were then smoked at 75ºC in an improved traditional smoking kiln followed by cooling. After sealing in polythene bags the smoked products were stored separately at ambient and refrigeration temperature. Four major analysis viz. sensory assessment, initial and final proximate analysis, chemical analysis and microbial analysis were carried out on the samples. According to sensory assessment the 30 minutes brine dipped smoked fish kept at ambient temperature showed a higher shelf-life of four days. On 5th day, appearance of fungus on the product of treatment B confirmed its acceptability up to 4 days. Similarly the samples of two treatments A and B stored at refrigeration temperature showed a longer shelf-life of up to 41 and 48 days respectively. The rate of lipid deterioration and protein breakdown were found very gradual and not significant. In all cases ash content increased slightly. No appreciable changes in proximate composition in two treatments during storage condition were observed. Values of TVB-N in the samples kept at ambient temperature showed more rapid increase to 34.6 mg/100g on 4th day of observation in contrast to 35.9 mg/100g on 49th day in fish kept at refrigeration temperature. However, smoked silver carp in treatment B maintained its excellent quality up to 14 days of storage, and considered as acceptable for 41days and was just to satisfactory level for 48 days under refrigerated condition.