Bioethanol: Experiences from running plants, optimization and prospects

In the past decades, the agro-industry in Europe has made a tremendous move from more regional to globally operating food groups processing a variety of different crops to agrochemicals, e.g. to carbohydrates such as sugars, starches and inulin. Moreover, these agrochemicals are feedstocks for a variety of further processed products. Biotechnology plays a central role in these material transformations. Besides a considerable number of developments using enzyme technology as 'chemical' catalysts, for example for the production of Palatinose (TM) (isomaltulose), isomalt, and oligofructosides or special inulins, fermentations are starting to become an important tool, too. When the EU made the move towards bio-fuels, European agro-industry decided to become a major player in this field. For bio-ethanol production, besides raw material the factors with the highest impact on overall costs are energy consumption and yield. To optimize both, innovative developments were successfully established for different process steps, including fermentation and enzymatic hydrolysis of starch and other bio-polymers. Further optimization of yeasts, for example by using gene modification technology, is possible. Besides specific energy saving techniques like multi effect evaporation and distillation, enzyme technology has made a great contribution to reduction in overall energy consumption. For further energy savings, improved enzymes are necessary and should be developed.