Assessment of sweet potato [Ipomoea batatas (L.) Lam] for bioethanol production in southern Italy

The potential of sweet potato as an alternative crop for bioethanol production has been assessed. We evaluated the amount of soluble sugars, starch and cell wall polysaccharides in tubers of three sweet potato cultivars characterized by different pulp and peel colouration: "Yellow yam" with yellow flesh and brown peel, "White yam" with white flesh and white peel and "Orange yam" with orange flesh and brown peel. The results confirm the high concentration of carbohydrates in sweet potato tubers, especially "Yellow yam", mainly in the form of starch (67%) and soluble sugars (26%). "Yellow yam", which is the most widespread cultivar in Salento, appeared the best choice as biomass for bioethanol production. It is characterized by high productivity (20-40tons/ha year). Results also suggest that "Yellow yam" cultivar has great potential as a bioethanol source in southern Italy with an estimated agroindustrial production yield higher than 2032l/ha year.