EFFECT OF POTASSIUM SORBATE AND MODIFIED ATMOSPHERE PACKAGING ON THE SHELF-LIFE EXTENSION OF SEER FISH (SCOMBEROMORUS COMMERSON)STEAKS DURING ICED STORAGE

Combined effects of vacuum packaging and mint extract treatment on the biochemical, sensory and microbial changes of chill stored Indian mackerel

The present study was aimed to investigate the combined effects of vacuum packaging and mint extract treatment on the quality changes of gutted Indian mackerel (Rastrelliger kanagurta) during storage at 0-2 °C for 22 days. Biochemical, total viable count and sensory quality of chill stored mackerel were analysed at periodic intervals. Mint extract treated [dipping in 0.5% (w/v) solution of mint extract for 30 min] and vacuum packed fishes (MEVP) had significantly lower total volatile base nitrogen and trimethyl amine nitrogen compared to those packed under vacuum (CVP) and air (CAP) without mint extract treatment. Nucleotide degradation rate was lower in MEVP followed by CVP and CAP. Vacuum packaging in combination with ME treatment significantly inhibited lipid hydrolysis and lipid oxidation in mackerel as observed from its lower free fatty acid, peroxide value and thiobarbituric acid reactive substances values. Synergistic use of mint extract and vacuum packaging has markedly controlled microbial proliferation in the samples. Based on sensory evaluation, shelf life of Indian mackerel stored at 0-2 °C was determined as 13 days for CAP group, 16 days for CVP group and 21 days for MEVP group, respectively. The present study revealed that combination of vacuum packaging and mint extract treatment can be a promising technology to improve the storage quality of chill stored gutted mackerel.

Preparation of an novel botanic biopreservative and its efficacy in keeping quality of peeled Penaeus vannamei

A novel botanic biopreservative was successfully prepared by the combination of the bamboo leaves extracts and ebony extracts, designated as ebony-bamboo leaves complex extracts (EBLCE), whose antimicrobial activity was assessed according to an inhibition zone method against 10 common pathogenic and spoilage microorganisms. It was found that EBLCE was more effective from all the chosen microorganisms, as compared by potassium sorbate. Due to its excellent antimicrobial activity, and some additional properties like edibility, safety and economy, EBLCE was selected for further study to evaluate the efficacy in prolonging shelf life and improving the quality of peeled Penaeus vannamei during storage at 4 °C, based on periodical microbiological, chemical and sensory analysis. As a result, EBLCE was observed to prevent spoilage of peeled P. vannamei efficiently as reflected by a distinct decrease in total viable count, pH and total volatile basic nitrogen, as well as a slower decline in the sensory evaluation scores. Therefore, a prolonged shelf life of 16 days was obtained for EBLCE pre-treated peeled shrimps with comparison of 6 days for the control group, demonstrating EBLCE as a promising alternative for preserving food.