Pure sugar is relatively easily converted to ethanol by a biochemical pathway (fermentation) in several steps. Production of a sugar solution from sugarcane and/or sugar beet is quite straightforward since fermentable carbohydrates can be obtained just by extracting the raw material with water. In the case of starch-based raw material, the process becomes a little bit more complicated. The fermenting organisms need mono — or disaccharides to produce ethanol, and since starch is a polymer, the fermentation rate is very slow. In order to increase the rate, the polymer has to be broken down into monomers. The polymeric starch in wheat or corn is stored in granules. When the granules are heated in water, the hydrogen bonds between the polymer chains are broken and a water solution of starch is formed. To this solution, enzymes called amylases and amyloglucosidases are added. These enzymes then hydrolyse the glycosidic bonds between the monomers which results in a solution of fermentable monomers. The amylases randomly cut the bond between two sugar units, reducing the chain length, while the amyloglucosidase peels off one sugar unit at a time from the ends of the chains. By themselves, these enzymes are very inefficient in cleaving the starch polymer into monomers, but working together (synergic effect) gives a very efficient hydrolysis.