Performance of microfiltration membrane in separating polyphenol from fermented red ginger (Zingiber officinale var. rubrum) by kombucha culture for natural antioxidant Available to Purchase

Microfiltration (MF) membrane performance in separation of red ginger (Zingiber officinale) through dead-end stirred filtration cell (DESFC) was conducted to concentrate with the best total polyphenol as natural antioxidant. Separation process of fermented red ginger of A and fermented red ginger of B were performed through MF membrane (pores size of 0.15 µm) fitted in DESFC at fixed trans-membrane pressure (TMP) of 20 psia, and stirrer rotation speed of 200, 300 and 400 rpm for 30 minutes. Fermented red ginger of A and fermented red ginger of B were the result of fermentation of red ginger with concentrations of red ginger extracts of 5 and 10% (v/v) by kombucha inoculum of 20% for 14 days at room temperature. The result of research showed that based on optimization of flux, the best DESFC performance on fermented red ginger of A and fermented red ginger of B were obtained at stirrer rotation speed of 400 rpm and TMP of 20 psia and gave fluxes of 0.0418 and 0.0342 mL/cm².min. At these condition of optimum flux were generated retentate of fermented red ginger of A and fermented red ginger of B with compositions of total polyphenol of 0.999 and 1.024%, total solids of 14.02 and 11.43 %, and inhibition of 89.82 and 89.57%, while permeates of fermented red ginger of A and fermented red ginger of B had compositions of total polyphenol of 0.929 and 0.527%, total solids of 12.75 and 10.68%, and inhibition of 91.25 and 90.24%. In these conditions of optimum fluxes, fermented red ginger of A and fermented red ginger of B showed mass spectra with polyphenol monomer dominated by Acetoxy-[8]-gingerol with molecular weight (MW) of 365.266 Dalton (Da.) and Diacetoxy-[6] gingerdiol with MW of 381.206 Da., and relative intensity of 100% and 37.63%, respectively.