Effects of pectin combined with plant essential oils on water migration, myofibrillar proteins and muscle tissue enzyme activity of vacuum packaged large yellow croaker (Pseudosciaena crocea) during ice storage

Abstract

The effects of pectin combined with plant essential oils on water migration, myofibrillar proteins (MPs) and muscle tissue enzyme activity of vacuum packaged large yellow croaker (Pseudosciaena crocea) during ice storage at 4±1°C were investigated. Two solutions of 2.5 % (w/v) pectin combined with 0.4 % (v/v) oregano essential oil (PO) and 0.4 % (v/v) ginger essential oil (PG) were used for coating treatments. Water holding capacity (WHC), cooking loss, Low-field nuclear magnetic resonance (LF-NMR) and Magnetic resonance imaging (MRI) analysis, carbonyl content, total sulfhydryl content, fluorescence intensity (FI) of myofibrillar protein and SDS-PAGE were analyzed, respectively. Tissue characteristics, including α-Glucosidase (AG) and β-N-acetyl-glucosaminidase (NAG) activities were measured. The results showed that compared to the CK group, LF-NMR and MRI results showed that PO and PG groups delay the transformation of mobilized water to free water and maintain better WHC during storage. PO and PG groups also had a significant protective effect on protein oxidation, such as the inhibition of carbonyl group and FI, prevention of endogenous enzyme activity, and a decrease in the sulfhydryl content. Therefore, PO and PG groups had the most optimal effect and could enhance the shelf life of large yellow croaker for another 7 days at least during ice storage.