(524d) Denaturation of Egg Yolk Proteins during Processing with near-Critical Dimethylether

Near-critical dimethylether (DME) is an effective solvent for extraction of polar and neutral lipids from natural compounds. Processing using DME however may cause some denaturation of residual proteins, particularly in the presence of water, and this may be undesirable in cases where the enriched protein fraction is a product of value. This work describes measurements of denaturation of egg proteins when DME is used to extract the lipid fraction from egg yolks. Both fresh and diluted egg yolks were processed using DME as an antisolvent to precipitate water and protein from the feed stream. Protein denaturation, based on changes in water solubility, was measured for different DME exposure times, processing temperatures, and water to DME flow ratios. Results show that the amount of water present in the system has a significant effect on changes in protein solubility.