Potato Granule Processing Line by-Products as Feedstock for Ethanol Production

Our research assessed fermentation characteristics of mashes prepared from oversized waste granules containing potato peel and potato dust formed during dried potato granule production. Due to the high water binding capacity of materials, applied fermentation was carried out at low gravities of 10 and 15% w/w of raw materials dry matter. Mashing of materials resulted in total soluble sugar (glucose, maltose, and maltotriose) concentrations ranging between 95.10 and 66.33 g·L. Fermentation dynamics evaluation showed that CO2 secretion was nearly over after 24 h. In all the samples collected, yeast utilized the whole amount of sugars after the first day of the process. Ethanol production by yeast ended after 24 h of the process, resulting in of 36.86-39.89 g·L concentration for 10% and 54.44-61.66 g·L for samples at 15% concentration. In both variants of concentration higher ethanol yield was obtained in aspiration channel dust.