Bioethanol from stale bread

Development of an economic process for the fermentation of starch-containing waste from the baking industry including the associated microorganism and enzyme formulations

Goal: The goal of the project partners Erbslöh Geisenheim AG and the OWL University of Applied Sciences and Arts is the development of an economic process for the fermentation of starch-containing waste from the baking industry, including the associated microorganism or enzyme formulations that are necessary for the operation of the process. Numerous residues were investigated for their bioethanol formation potential. Supply and utilisation paths for corresponding residues were identified. A stable pilot plant process was developed, on the basis of which the expected yields were determined and achieved. A large-scale trial in a distillery proved the large-scale application capability. The specific technical requirements of the process were identified. At least two distilleries already recycle residues for bioethanol production. The nationwide amount of returned and residual bread is estimated at 600,000 t/a based on our research. The average yield is 280 ml EtOH/kg of waste bread. Accordingly, the annual potential at a residual moisture of 35 % is 168,000 m³/a EtOH or 1292 GWh calorific calorific value for waste bread only for Germany.

Contact: Prof. Dr.-Ing. Jan Schneider, Timo Broeker

Cooperation partner: Erbslöh Geisenheim

Funding programme: Alliance for Industrial Research (AiF) e.V., ZIM programme

Funding code: KF 2402601 SK9

Project duration: 2009 – 2011