Impact of pulsed electric field assisted vacuum impregnation of chitooligosaccharide-epigallocatechin gallate conjugate and hydrocolloids on quality and shelf-life of Asian hard clam

This study aimed to enhance the shelf-life and quality of Asian hard clam (HC) using pulsed electric field (PEF) pre-treatment, vacuum impregnation (VI), and natural additives. PEF-treated HC were infused with psyllium husk (PH, 0.5-2 %; <i>w</i>/<i>v</i>) or κ-carrageenan (KC, 0.5-2 %; w/v), in which 2 % PH yielded the highest weight gain and lowest cooking loss. HC was further treated with chitooligosaccharide-epigallocatechin gallate conjugate (CEC, 2-3 %; w/w) without and with PH, then stored at 4 °C for 15 days. Histology confirmed structural changes in the muscle by PEF, especially in combination with CEC and PH. Microbial counts in 3 % CEC-treated HC remained below 5 log CFU/g sample until day 12. Lipid oxidation was suppressed and fatty acid analysis showed preservation of PUFA. Integration of PEF pre-treatment with CEC and PH infusion preserved clams for 12 days with lower cooking and quality losses, indicating a synergistic effects on HC preservation during refrigerated storage.