Techno-Economic assessment of α-Lactalbumin and β-Lactoglobulin fractionation from whey protein isolated solution using supercritical carbon dioxide in a continuous reactor

Abstract

Growing interest in healthy lifestyles and muscle building has led the increasing consumption of dairy food supplements. However, the allergic reactions to whey products has driven the research efforts towards fractionation and enrichment of specific whey proteins, like α-Lactalbumin and β-Lactoglobulin. This research presents the techno economical assessment of a continuous fractionation process of α-Lactalbumin (α-La) and β-Lactoglobulin (β-Lg) using supercritical carbon dioxide (scCO2) at laboratory-scale with an aim to scale up this process to industrial application. The effect of pressure and temperature on the precipitation reaction of proteins was investigated in the range of 8–24 MPa and 50–60 °C, respectively. The fractionated product was composed of 47.5% α-Lactalbumin and 11.2% β-Lactoglobulin, enhancing α-Lactalbumin selectivity five times compared to that of initial whey. The process modeling and simulation were carried out using the Aspen Plus software. The economic analysis estimates that the manufacturing cost of a plant processing 6984 tons per year of a 5% whey protein isolated solution is 2.40 US$/kg. Through techno-economic analyses, it was possible to confirm that continuous fractionation is an economically interesting alternative for large-scale production of enriched α-La and β-Lg streams compared to technologies found in the literature, as membrane separation, adsorption, and semi-continuous process using scCO2, resulting in the valorization of cheese whey, which is still considered as a waste in the cheese industry.