POSSIBLE SUBSTRATES FOR ACETONE–BUTANOL AND ETHANOL FERMENTATION BASED ON ORGANIC BY-PRODUCTS

Abstract

An assessment study was carried out on available biomass by-products in Hungary, and also several fruit juice wastes were evaluated for their accessibility to enzymatic hydrolysis. Among the fruit juice residue samples examined the best results were obtained with apple, peach, apricot and tomato. It can be shown that using intensive stirring, higher conversions can be reached. Highest conversion of 98% - based on carbohydrate content - was obtained with frozen and thawed apple residues. ABE fermentation of apple pulp hydrolysate supplemented with glucose yielded high solvent concentrations up to 22.5 g/l. For growth and solvent production supplementation by additional nutrients was not essential, however, this accelerated the process. Ethanol fermentation by baker’s yeast was carried out on apple pulp hydrolysate supplemented with glucose. This also gave reasonable yields of about 90% - based on glucose consumption.