These residues end up in the stillage, a by-product which in the end is dried and used as animal feed. In this project currently undegraded feedstock left in the whole stillage will be convertet into bioethanol using edible filamentous fungi and improve the quality of the animal feed. The project is carried out within the research area Resource Recovery and carried out in collaboration with Lantmännen Agroetanol, the only full-scale producer of fuel ethanol in Sweden, and Lantmännen Energi.
Filamentous fungi are well known to be able to degrade complex organic material, such as starch, hemicellulose, cellulose and proteins. Compared with baker’s yeast (Saccharomyces cerevisiae) that is used on current ethanol production this is a clear advantage. However, some filamentous fungi can also cause severe health problems and disease in e.g. humans and other animals. Since current starch-based industrial ethanol producers receive appr. 1/3 of their income from the by-product DDGS (Distiller’s Dried Grains and Solubles) which is sold as animal feed this calls for caution. Thus, a new type of organism incorporated into the process has to be safe for consumption. The most secure way of ensuring safety is to use filamentous fungi. Preliminary experiments using edible filamentous fungi have indicated that some are able to degrade part of the by-products from current industrial scale ethanol production and simultaneously produce ethanol.