Goat milk proteins enriched with Agaricus blazei Murrill ss. Heinem extracts: Electrophoretic, FTIR, DLS and microstructure characterization

Abstract

This study aimed to characterize mixtures of goat milk proteins and Agaricus blazei Murrill (ABM) extracts (aqueous, AE and polysaccharides, PE). The mixtures showed stable particles with ζ-potential more negative than −41.1 mV. The addition of AMB extracts to goat milk did not result in a significant particle size change, whereas their addition to heated goat milk significantly increased mean particle diameter (from 194 nm to 225 nm). Fourier Transform Infrared Spectroscopy (FTIR) showed that ABM extracts provoked changes in the secondary structure of goat milk proteins and interactions between polysaccharides and milk proteins predominantly via hydrogen and/or glycoside bonds and hydrophobic interactions. The milk protein profiles revealed proteolytic activity in mixtures with AE resulting in the formation of five new polypeptides. The different microstructures of mixtures with AE and PE were found by Scanning Electron Microscopy (SEM). A schematic representation of possible milk proteins-ABM extracts interactions has been given.