Component partitioning during microfiltration and diafiltration of whey protein concentrate in the production of whey protein isolate

This study investigated component partitioning during cold microfiltration (MF) and diafiltration (DF) of whey protein concentrate (WPC) feed in producing whey protein isolate (WPI). Significant differences (P < 0.05) were found in the partitioning of components. Specifically, 60.1, 50.2, 6.32, and 75.7% of total solids, protein, fat, and ash, respectively, were partitioned into the permeate stream. Phospholipids comprised 25 and 41.4% of total fat in WPC feed and DF retentate, respectively. Sodium dodecyl sulphate-polyacrylamide gel electrophoresis showed MFGM-associated proteins were enriched in the MF retentate. The particle size in MF retentate was significantly larger (P < 0.05) than in the MF and DF permeate streams (450, 7.87, and 3.55 nm, respectively), providing evidence of the retention of aggregated whey proteins in the MF retentate. These findings provide an indepth understanding of component partitioning during cold MF of WPC feed, supporting the development of higher value-added ingredients.