There are many possibilities for valorization of stillage from bioethanol processing. Some of them are the stillage recirculation and reuse [54–58], production of soil fertilizers [55], anaerobic fermentations for the production of lactic acid or butanol [59–63] and the production of various types of animal feed [64–72]. In USA, around 85% of the liquid stillage has been dried together with spent grains to produce dry distiller’s grains with solubles (DDGS) which are used as animal feed. In Europe, the most of the stillage for animal feed is used in wet form because the drying itself is a costly process which requires a lot of energy [55]. In the majority of industrial facilities in Serbia, the bioethanol by-products have not been utilized, posing therefore a hardly solvable environmental problem The complex composition of stillage causes high BOD5 values which range from 15–340g/L [54].