Tham khảo tài liệu 'bioethanol part 4', khoa học tự nhiên, công nghệ sinh học phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | 50 Bioethanol Zhang L. Chen Q. Jin Y. Xue H. Guan J. Wang Z. Zhao H. 2010 . Energy-saving direct ethanol production from viscosity reduction mash of sweet potato at very high gravity VHG . Fuel Processing Technology 91 pp. 1845-1850. 3 Sorghum as a Multifunctional Crop for the Production of Fuel Ethanol Current Status and Future Trends Sergio O. Serna-Saldívar Cristina Chuck-Hernandez Esther Pérez-Carrillo and Erick Heredia-Olea Departamento de Biotecnología e Ingeniería de Alimentos Centro de Biotecnología. Tecnológico de Monterrey Monterrey N. L. Mexico 1. Introduction Nowadays there is a growing interest for alternative energy sources because of the reduction of fossil fuel production. Ethanol used as automotive fuel has increased at least six times in the current century. According to the Renewable Fuels Association in 2010 the USA bio-refineries generated 13 billion gallons of fuel ethanol and the year before worldwide production reached 19 billion. This noteworthy increment is in its majority based on maize and sugar cane as raw materials Berg 2004 Renewable Fuels Association 2010 . The use of these feedstocks has triggered concerns related to food security especially today when the world population has reached 7 billion people. The relatively sudden rise in food prices during 2008 2010 and 2011 has been attributed mainly to the use of maize for bioethanol even when other factors like droughts or changes in global consumption patterns have also played a major role World Food Program 2008 . Food price projections indicate that this situation will worsen breaking the downward trend registered in food prices in the last thirty years The Economist 2007 . Even if there was not a food-fuel controversy especially due to the current conversion of millions of tons of maize for bioethanol the use of only this crop cannot support the ambitious objectives of renewable fuel legislation in countries like the United States of America where a target of 36 billion gallons of
