Inactivation of Endogenous Pectin Methylesterases by Radio Frequency Heating during the Fermentation of Fruit Wines

Pectin methylesterase (PME) is a methyl ester group hydrolytic enzyme of either plant or microbial origin. Importantly, endogenous PMEs in fruits can catalyze the demethoxylation pectin with bulk release methanol, largely impacting fruit juice and wine industries. Here, we demonstrated radio frequency (RF) heating for inactivation investigated relevant mechanisms underpinning enzymatic inactivation. The RF curve indicated that optimal rate was achieved at an electrode gap 90 mm (compared to 100 110 mm) increases time. exhibited better effects on than traditional water heating, mainly by changing secondary structures PMEs, including α-helix, β-sheet, β-turn, random coil. Moreover, fluorescence spectroscopy changes tertiary structure significant increase intensity. Significantly, application resulted 1.5-fold decrease methanol during fermentation jujube wine. Collectively, our findings effective approach inactivating bioprocesses fruits.