Foam Fractionation of a-lactalbumin and beta-lactoglobulin from Whey Solution

摘要

Whey, a byproduct of cheese production, is often considered a waste stream and typically transported out of dairy plant for a per volume charge. One possible method to reduce the waste volume and disposal cost is to concentrate whey by foam fractionation and potentially produce a valuable co-product, a concentrated whey protein solution. Foam fractionation is an adsorptive bubble separation method that is based on the hydrophobic/ hydrophilic properties of proteins. In this study, foam fractionationwas evaluated for the concentration of whey proteins specifically a-lactalbumin and f3-lactoglobulin from a dilute whey protein isolate (WPI) solution. The effects of initial whey protein concentration (0.075 and 0.15 mg/mL), pH (3.8-5.5), and superficial gas velocity (0.85 and 0.95 cm/sec) on protein enrichment and recovery were examined. Higher enrichment was achieved with the lower initial protein concentration (0.075 mg/mL), andatpH values that were around to the isoelectric points (pi) of a-lactalbumin and p-lactoglobulin (pH 3.8, 4.2, 4.5, and 5.2). The higher superficial gas velocity enhanced the amount of proteins recovered from the dilute solution, but with a decrease in the enrichment.