Raw materials (containing saccharides) include sweet sorghum, sugar beet, banana, mango, watermelon, sug­arcane and other fruits; these are examples of sugar feedstock. The wastes of these sugar-containing sources can be fermented by using different microorganisms of interest. However, the use of these materials for
bioethanol production is highly expensive and humans use them as food (Kahn et al., 2011).

The first research about bioethanol showed in Table 3.1 reports the production of biofuel using resi­dues of fruits and vegetables. These are an important source of sugar for ethylic fermentation because the pro­cessing of fruits have a great potential to generate resi­dues that can be used. The authors report the use of enzymes in the process; this is necessary because these residues have a lot of fiber that can be hydrolyzed (Patle and Lal, 2007). The use of wastes is the main aspect of two other studies (Gouvea et al., 2009; Ge et al., 2011). Gouvea et al. (2009) reported the use of a residue very abundant in Brazil, that is, the coffee husk. As well as in the case of fruit and vegetable residues the floating seaweed wastes have other kinds of carbohydrates that were hydrolyzed by enzymes (Wu et al., 2011). Ge et al. (2011) reported the use of a principal sugar source for ethylic fermentation, the stalk juice of sugarcane. This juice has great quantity of glucose in its composi­tion and has a low cost. More studies about sugarcane juice were omitted since the main subject of this chapter is agroindustrial residues.