Application of a decanter centrifuge for casein fractionation on pilot scale: Effect of operational parameters on total solid, purity and yield in solid discharge

Individual casein fractions are of growing interest because of their multifunctional applications. The fractions of caseins (αS-, β- & κ-) possess a wide range of bio- and techno-functional properties. Although various isolation and purification methods to obtain casein fractions have been reported, there is still a need for improvement, especially on a technical scale. The aim of this study was to develop and establish a continuous process for the fractionation of caseins. The fractions were obtained from micellar casein by means of selective precipitation. The separation process was performed using a temperature-controlled decanter centrifuge. Enrichment of the fractions was optimised by altering the operational parameters of the decanter (inner weir diameter (Øweir), centrifugal force (FZ), differential speed (Δn), flow rate (V̇)). A 95% pure casein fraction containing αS- and β-casein was obtained. The purity and yield of the κ-casein fraction were 54% and 83%, respectively.