Fig. 2. Formation of ethanol (a), glycerol (b) and lactic acid (c) during direct starch to ethanol conversion process of waste wheat rye-bread media with GSHE (I – unpretreated
variant, II – enzymatic pretreatment, III – microwave pretreatment, IV – ultrasonic pretreatment, V – SHF process). Results expressed as mean values ± standard deviation
(n = 3).