Whey bio-valorization by fermentation with Saccharomyces cerevisiae

Abstract

Whey is a dairy by-product and can be view as a co-product due to its high valuable organic content, which can cause environmental harassment if it is not treated adequately. The aim of this study was to evaluate the ethanol production by fermentation of cheese whey in small companies. The yeasts Saccharomyces cerevisiae were used to provide the alcoholic fermentation. The analyses of acidic on acid lactic, ashes, lactose, protein, fat and total dry extract were determined. The preliminary results characterized whey as an acid type showing 0.12% on acid lactic, moreover, relevant organic content was observed with 5.66% of total dry extract, 4.1% lactose content and 1.2% of protein. The fermentation was performed in laboratorial bioreactors on triplicate for 24h and the parameters monitored were the ethanol production, temperature and pH in the media considering substrate, sucrose and inoculums incoming. The experiment was conducted with the addition of 100g.L-1 of sucrose and 6.0g.L-1 of inoculums. The medium ethanol production found was 5.3% (v/v)± 0.1, with pH showing stability during the process with low variations. The utilization of Saccharomyces cerevisiae for alcoholic fermentation has shown a satisfactory ethanol production, showing also as a good alternative for whey valorization.

Keywords: whey, ethanol, bioreactors.