The cane juice or garapa is then filtered and treated by chemicals and pasteurized. Before evaporation, the juice is filtered once again, producing vinasse, a fluid rich in organic compounds. The syrup resulting from evaporation is then precipitated by crystallization producing a mixture of clear crystals surrounded by molasses. A centrifuge is used to separate the sugar from molasses, and the crystals are washed by addition of steam, after which the crystals are dried by an airflow. Upon cooling, sugar crystallizes out of the syrup. From this point, the sugar refining process continues to produce different grades of sugar, and the molasses continue a separate process to produce ethanol. The resulting molasses are treated to become a sterilized molasse free of impurities, ready to be fermented. In the fermentation process sugars are transformed into ethanol by addition of yeast. Fermentation time varies from four to twelve hours resulting in an alcohol content of 7-10% by total volume (°GL), called fermented wine. The yeast is recovered from this wine through a centrifuge. Making use of the different boiling points the alcohol in the fermented wine is separated from the main resting solid components. The remaining product is hydrated ethanol with a concentration of 96°GL, the highest concentration of ethanol that can be achieved via azeotropic distillation, and by national specification can contain up to 4.9% of water by volume. This hydrous ethanol is the fuel used by ethanol-only and flex vehicles in the country. Further dehydration is normally done by addition of chemicals, up to the specified 99.7°GL in order to produce anhydrous ethanol, which is used for blending with pure gasoline to obtain the country's E25 mandatory blend. The additional processing required to convert hydrated into anhydrous ethanol increases the cost of the fuel, as in 2007 the average producer price difference between the two was around 14% for São Paulo State. This production price difference, though small, contributes to the competitiveness of the hydrated ethanol (E100) used in Brazil, not only with regard to local gasoline prices but also as compared to other countries such as the United States and Sweden, that only use anhydrous ethanol for their flex fuel fleet. Since the early days, bagasse was burnt in the plant to provide the energy required for the industrial part of the process. Today, the Brazilian best practice uses high-pressure boilers that increases energy recovery, allowing most sugar-ethanol plants to be energetically self-sufficient and even sell surplus electricity to utilities.