Technological Approaches to Industrial Whey Processing

Whey is a by-product of dairy production. This valuable resource contains up to 50% of all nutrients in the original milk. Modern dairy science has to solve three key tasks: 1) efficient extraction of such valuable components as proteins, lactose, and minerals; 2) environmental sustainability; 3) new industrial applications. This article reviews various methods of whey processing, their effectiveness, advantages, limitations, and industrial prospects. Ultrafiltration makes it possible to reach 80% protein concentration (dry matter). Nanofiltration provides demineralization and concentration as high as 18-20%. Reverse osmosis concentrates whey to a mass fraction of 18-20%. Ion-exchange chromatography complements these methods in the pharmaceutical industry by protein fractionation. During electrochemical processing, electric current passes through whey located between electrodes, which are separated by an ion-permeable membrane. This type of processing creates a concentration of anions and cations that corresponds to the isoelectric point of protein coagulation. Enzymatic hydrolysis opens up new opportunities for obtaining bioactive peptides with reliable antioxidant, antimicrobial, and hypotensive properties. Each of the abovementioned methods has certain limitations. For instance, membrane processes require careful preliminary preparation and are associated with such phenomenon as concentration polarization. Thermal methods are energy intensive while enzymatic methods depend on the activity and stability of enzyme preparations. By combining these methods, dairy producers achieve deep processing and perform selective isolation of target fractions. Advanced whey processing technologies provide new sustainable opportunities, promoting the dairy industry to the stage of circular economy.