Evaluation of fouling during ultrafiltration process of acid and sweet whey

Membrane fouling caused by deposition of whey protein on the membrane surface is still the major factor limiting concentration and fractionation efficiency in dairy industry. This work aims to elucidate the mechanisms of membrane fouling during ultrafiltration (50 degrees C) of sweet and acid whey obtained after Gouda and Tvarog (acid-coagulated cheese) manufacture using 20 nm ceramic membrane. A resistance-in-series model that accounts for time evolution of hydraulic resistances was considered. The results demonstrated that the higher the protein content the greater the total hydraulic resistance. Moreover, the resistance due to adsorption and con-centration polarization dominated from the first minutes of filtration, whereas the growth of cake layer was much slower and gradual for each feed tested. SDS-PAGE electrophoresis showed that alpha-lactalbumin and beta-lactoglobulin were the main contributors to pore blocking.

Automated summary

This study investigated the mechanisms of membrane fouling caused by the deposition of whey protein on the membrane surface during ultrafiltration. Results showed that higher protein content led to greater total hydraulic resistance, with adsorption and concentration polarization dominating the resistance in the initial minutes of filtration.