Progress in the development of methods used for the abatement of microbial contaminants in ethanol fermentations: a review

Biofuel research and development roadmap is currently underway in several countries and is expected to pave a way for the establishment of a viable renewable energy sector that can compete with petroleum-based fuels. Ethanol fermentation has garnered increasing attention amongst various stakeholders (industries, governments, and academia) due to its economic and environmental merits. However, microbial contamination continues to be one of the major barriers in ethanologenic processes, resulting in low ethanol yields and thereby translating into economic losses. To this end, technological innovations geared towards effective elimination of microbial contamination are constantly being developed. This review explores and discusses the fermentation conditions that facilitate the growth of undesired microorganisms during ethanol fermentation processes. It highlights the methods that are currently used in biorefineries as well as innovative and advanced biotechnological methods currently being evaluated as viable alternative strategies to control or eliminate microbial contaminants in ethanol fermentations. These methods have the potential to minimize or control the contamination problem and could pave a way for the development of an efficient biofuel sector.