The combined effect of squid pen chitooligosaccharides and high voltage cold atmospheric plasma on the shelf-life extension of Asian sea bass slices stored at 4 °C

Abstract

Combined effects of high voltage cold atmospheric plasma (HV-CAP) generated with the mixture of argon and oxygen (90%Ar/10%O2) for 5 min and chitooligosaccharide (COS) from squid (Loligo formosana) pen (internalized shell) at different concentrations (0.05, 0.1 and 0.2 g/100 g fish slices) on the shelf-life of Asian sea bass (ASB) slices were investigated during storage at 4 °C for 18 days. Total viable count (TVC) of fish slices treated with 0.1 or 0.2 g/100 g COS in conjunction with HV-CAP was lower than the acceptable limit (log 106 CFU/g sample) within 18 days. The growth of various pathogenic and spoilage bacteria including psychrophilic bacteria, Clostridium perfringens (not detected), lactic acid bacteria (3.77–4.37 log CFU/g), Enterobacteriaceae (4.03–4.50 log CFU/g), Pseudomonas (6.62–6.82 log CFU/g) and hydrogen sulphide (H2S)-producing (4.04–5.05 log CFU/g) bacteria of HV-CAP-treated slices containing COS was more inhibited than other treatments, especially during the first 15 days of storage. The thiobarbituric acid reactive substances (TBARS) and peroxide values (PV) of slices treated with combined HV-CAP and COS (0.1 or 0.2 g/100 g) were reduced by 28‐–64 and 40–46%, respectively than those treated with only HV-CAP throughout the storage (p <.05). Similarly, for HV-CAP treated slices, addition of COS decreased the total carbonyl content by 15–24% than those added without COS. COS was able to lower the oxidation of polyunsaturated fatty acids of slices caused by HV-CAP. Therefore, HV-CAP together with COS effectively prolonged the shelf-life of ASB slices with sensory acceptability at 4 °C for at least 12 days.