Ionic liquid‐based three phase partitioning (ILTPP) systems for whey protein recovery: ionic liquid selection

Abstract

AbstractBACKGROUNDThe ionic liquid three phase partitioning (ILTPP) technique is a promising alternative to conventional processing technologies for protein separation and purification since it allows protein recovery at the liquid–liquid interface. In previous work, ILTPP has been developed with the BmimBF4/NaH2PO4 system for lactoferrin recovery, a bovine whey protein with important nutraceutical properties. However, BmimBF4 may suffer from hydrolysis when it is in contact with water, so the selection of an alternative ionic liquid with similar results regarding lactoferrin recovery should be sought.RESULTSThe system based on BmimTfO and phosphate is selected as the most suitable since it combines relatively high LF recoveries at the liquid–liquid interface (83–99%) and chemical stability. The highest LF recoveries occur at moderate acidic pH (3.1–4.0), which may also be improved at relatively low protein concentrations. The process selectivity with respect to bovine serum albumin (another whey protein) varies from 1.1 to 3.0, depending on experimental conditions.CONCLUSIONILTPP is a promising technique to recover the protein fraction from bovine whey or to enrich specific proteins such as lactoferrin, so ILTPP could replace alternative techniques such as membranes. The risk of hydrolysis associated with previous ionic liquid ILTPP systems has been successfully overcome. © 2014 Society of Chemical Industry