Bioconversion of electro-activated lactose, whey and whey permeate to produce single cell protein, ethanol, aroma volatiles, organic acids and fat by Kluyveromyces marxianus

Abstract

This study produced biomass and valuable metabolites through fermentation of electro-activated whey (EA-whey), electro-activated whey permeate, and electro-activated lactose using Kluyveromyces marxianus ATCC 64884. The fermentation process was performed for 96 h at 30 °C and 150 rpm. The results showed that all substrates provided a satisfactory biomass growth and EA-whey achieved a maximum biomass of 4.23 g L−1. Several major organic acids including lactic, acetic, citric, propionic acids were produced during the fermentation of all media, with differences between electro-activated and none-electro-activated substrates. K. marxianus produced various volatile aroma compounds such as ethanol, 2-phenylethanol, and isoamyl alcohol with valued organoleptic properties. The highest ethanol (28.13 g L−1) was produced in the non-electro-activated whey. These findings suggest that electro-activation can be used to improve the performance of K. marxianus driven bioprocesses using whey-based substrates to produce valuable metabolites for different applications, including in foods.