Heat-Induced Soluble Protein Aggregates from Mixed Pea Globulins and β-Lactoglobulin

The present work investigates the formation of protein aggregates (85 degrees C, 60 min incubation) upon heat treatment of beta-lactoglobulin (beta lg) pea globulins (Glob) mixtures at pH 7.2 and 5 mM NaCl from laboratory-prepared protein isolates. Various beta lg/Glob weight ratios were applied, for a total protein concentration of 2 wt % in admixture. Different analytical methods were used to determine the aggregation behavior of mixed aggregates, that is, surface hydrophobicity and also sulfhydryl content, protein interactions by means of SDS-PAGE electrophoresis, and molecule size distribution by DLS and gel filtration. The production of mixed thermal aggregates would involve both the formation of new disulfide bonds and noncovalent interactions between the denatured beta lg and Glob subunits. The majority of mixed soluble aggregates displayed higher molecular weight and smaller diameter than those for Glob heated in isolation. The development of pea whey protein mixed aggregates may help to design new ingredients for the control of innovative food textures.