Potential Use of Cross-flow Microfiltration System in Separation of Functional Compound from Fermented Beetroot (Beta vulgaris L.) as Natural Oxidation Prevention

Abstract

This study was conducted to determine the potential utilization of microfiltration (MF) membrane in separating functional compounds from beetroot (Beta vulgaris L.) biomass as a functional drink for natural oxidation prevention. Separation was performed through MF membrane (pore size of 0.15 µm) at room temperature, flow rate ~7.5 L/min, and TMP 2 and 6 bar for 0, 5, 15, 25, and 35 minutes. The results showed that process optimization based on gallic acid as total polyphenols and acetic acid were achieved at TMP 2 and 6 bar for 35 minutes, respectively. At TMP 2 and 6 bar produced retentate with acetic acids 1.24 and 0.95%, gallic acid 0.42 and 0.41%, total solids 3.49 and 3.47%, total sugars 36.64 and 44.66 mg/mL, pH 3.11 and 3.10, and inhibiting ability of 62.45 and 58.48%, respectively, meanwhile permeate had acetic acid 0.73 and 0.82%, gallic acid 0.31 and 0.33%, total solids 3.39 and 3.38%, total sugars 40.95 and 61.56 mg/mL, pH 3.12 and 3.13, inhibiting ability of 47.62 and 52.43%, respectively. In these conditions, CF-MF is technically able to retain acetic acid (2.63-folds) and gallic acid (1.21-folds) in the retentate and increase inhibition by 25.12 and 11.25% in comparison with the initial process (0 minutes). The LC-MS analysis of permeate at TMP 2 and 6 bar for 35 minutes were predominated by monomers of acetic acid and gallic acid with MW 61.2450 Da. (M+) and 193.0327 Da. (M+Na+) and relative intensities 100 %.