Fermented Beetroot (Beta vulgaris L.) Extract by Kombucha as Energy Booster Produced via Cross-Flow Microfiltration Membrane

Abstract

Beetroot extract (permeate) fermented by kombucha culture separated through cross-flow microfiltration (CFMF) with pore size 0.15 μm at TMP 2 and 6 bar for 0, 5, 15, 25, and 35 minutes, with a flow rate of 7.5 L/m3.hour, at room temperature potentially serves as a natural energy booster. The research results based on soluble protein show that the optimization process at TMP 2 and 6 bar was achieved at 15 minutes with permeate flux of 32.52 and 28.05 L/m3.h, respectively, and soluble protein content of 0.72 and 0.38 mg/mL, total solids of 3.40% and 3.36%, total sugar of 45.91 and 47.47 mg/mL, and acetic acid of 0.93 and 0.97%. Under these conditions, the CFMF system increased the soluble protein in permeate by 123.53% or 1.23 times, indicating partial rejection, and 22.58% or complete rejection. The identification of amino acids in the optimum condition was dominated by three threonine monomers with molecular weights of 120.11, 120.37, and 120.90 Da (M+), and six tryptophan monomers with molecular weights of 205.11, 205.21, 205.44, 205.60, 205.88, and 205.94 Da (M+). The permeate under optimum conditions had average particle sizes of 2788.0 nm and 2922.0 nm, with particle index of 1.523 and 1.795. The particle distribution in permeate at TMP 2 and 6 bar was less than 10,000 nm in size.