Dealcoholization of kiwi wine by forward osmosis: Evaluation of membrane fouling propensity and product quality

Abstract

Forward osmosis (FO) was used to dealcoholize kiwi wine (KW). The effect of dealcoholization on the physiochemical characteristics of KW, and on the CTA-FO membrane, was determined for three draw solutions (DSs) frequently used in FO, i.e., MgCl2, NaCl, and KCl. The highest water flux (11.1 L/m2h) and lowest alcohol content (0.45 v/v) were observed for MgCl2 DS. Fourier transform-infrared spectroscopy established that the three DSs did not significantly change the functional groups of the membrane surface. Scanning electron microscopy and atomic force microscopy confirmed that the least contaminated membrane was that used for MgCl2 DS dealcoholization. Furthermore, MgCl2 DS dealcoholized KW contained the greatest variety (n = 23) and highest content of volatile organic compounds (2735.36 μg/mL), and the highest phenolic content (91.59 μg/mL); it also displayed the highest antioxidant activity. The experimental results confirmed the suitability of FO for the dealcoholization of KW.