Effect of driving pressure and flux rate on red wine nanofiltration

Red wine contains many bioactive components, such as phenolics, which play a beneficial role on human health and also are responsible for important sensory qualities of wine. Membrane technology offers advantages compared to the conventional methods used for polyphenols extraction in terms of high recovery/removal efficiency, no phase transition and mild operating conditions. In this study, nanofiltration of the native Bulgarian red wine Mavrud was performed. The MaxiMem membrane filtration system employing the nanofiltration membrane Microdyn Nadir ™ NP030 P (MWCO 500 Da) was used for this purpose. The effects of the operating parameters (transmembrane pressure and flow rate) on the retention of bioactive compounds in wine were investigated. The phenolic amount of the obtained wine after nanofiltration was evaluated and compared with the data of the original wine. It was found out that the examined nanofiltration membrane can be effectively used for concentration of phenolics in wine. Optimal results with 29 % concentration of the phenolics in the obtained wine were achieved applying two sets of pressure and flow rate, namely 40 bar and 1.2 L/min, and 30 bar and 3 L/min.