Bioethanol – What Has Brazil Learned About Yeasts Inhabiting the Ethanol Production Processes from Sugar Cane?

Abstract

According to Datagro (the largest Brazilian sugar and ethanol consulting firm), Brazil will produce nearly 25.3 billion liters of ethanol in the year 2011 (UDOP, 2011). In spite of the astonishing amount, the country does not figure as the world’s largest producer, but certainly the bioethanol produced in Brazil stands out in the worldwide clean energy scenario. Ethanol is classified by the US Environmental Agency as an advanced biofuel, since it is capable of reducing greenhouse gas emissions up to 61% when compared to gasoline (UNICA, 2011). This significant production started in the 1970s, leveraged by the first oil crisis. The Brazilian government launched the Proalcool (National Alcohol Program). The required feedstock, sugar cane, has always been plentiful in a country with sugar production tradition. Many plants installed for sugarcane production already had fermentation units to treat molasses, a sugar manufacturing effluent. The government offered incentive to the creation of autonomous distilleries (using sugarcane juice as the only feedstock). In 1986, out of the 758,965 passenger vehicles manufactured in Brazil, 697,049 were fueled by bioethanol. The end of government incentives to bioethanol production and Brazilian consumers’ disbelief in face of bioethanol scarcity in fuel station pumps, associated with the reversion of the worldwide oil crisis, changed the Brazilian scenario. In 1998, out of the 1,389,958 passenger vehicles manufactured in Brazil, only 1,224 were fueled by bioethanol (UNICA, 2011). It seemed as the end of the bioethanol as an alternative fuel source. Many autonomous distilleries were converted into sugar factories, fermenting molasses only as an alternative for effluent treatment. Others were simply closed. In the 1990s, the eminent global warming threat awakened the world to the need to promote the use of renewable fuels. Ethanol production was quickly resumed in Brazil. In 2001, 16 billion liters of ethanol were produced in the country, and in 2009 this figure escalated to 27 billion liters (UNICA, 2011). In the 1990s, the flex-fuel car (running on ethanol or gasoline)