Microwave irradiation treatment improved the structure, emulsifying properties and cell proliferation of laccase-crosslinked α-lactalbumin

Abstract

Abstract Influence of microwave irradiation heating (MH) and water bath heating (WH) pretreatments (70, 80 and 90\xa0°C) on the structure, emulsifying properties and cell proliferation of laccase-crosslinked α-La was investigated. Compared with WH pretreatment, MH pretreatment can further promote the formation of polymers in laccase-crosslinked α-La. Also, MH treatment further unfolded the secondary structure, increased the surface hydrophobicity, and induced more formation of dityrosines in laccase-crosslinked α-La solution than that of WH pretreatment. Compared with untreated laccase-crosslinked α-La, its emulsifying activity index (EAI) was increased by 28.87% and 25.01% after MH and WH pretreatment at 90\xa0°C. Gel hardness and water holding capacity of laccase-crosslinked α-La was increased by 30.20% and 18.37% after MH at 90\xa0°C compared to untreated laccase-crosslinked α-La. Cell viability of laccase-crosslinked α-La (2\xa0mg/mL) was increased by 18.12% at 90\xa0°C with MH pretreatment. These findings indicated that MH pretreatment could ameliorate the crosslinking degree of α-La and laccase, thus improving its emulsifying, gel properties, and cell viability.