Structural and compositional changes of whey protein and blueberry juice fermented usingLactobacillus plantarumorLactobacillus caseiduring fermentation

Abstract

This study aimed to improve the stability of the anthocyanins and phenolic acids of blueberry by forming hydrogen bonds or hydrophobic interactions with whey protein using lactic acid fermentation. The effects of the initial pH on the characteristics of the whey protein and blueberry juice system fermented usingLactobacillus plantarumandLactobacillus caseiwere investigated. The color and total phenol and anthocyanin contents of the blueberry juice and whey protein system became stable after fermentation usingLactobacillus plantarumandLactobacillus casei. Fluorescence measurements and Fourier transform infrared spectroscopy (FTIR) analysis reveal that the characteristics of whey protein and blueberry juice changed significantly after fermentation usingLactobacillus plantarumandLactobacillus caseiindicating the binding of anthocyanins or phenolic hydroxyl groups of blueberry to N-H, C-N and C-O groups of whey protein. The α-helix content of whey protein and blueberry fermented usingLactobacillus plantarumalone decreased by 18% and β-sheet content increased by approximately 27% compared to whey protein fermented usingLactobacillus plantarum.