Effect Of Nitrogen Fertilizer And Different Processing Methods On The B-Carotene (Provitamin A) Content Of Selected Sweet Potato (Ipoinoea Batatas (L) Lam) Varieties

ABSTRACT 

Sweet potato, Jpomoea balatas (L) Lam, is a perennial plant grown normally as an annual (Woolfe, 1992). It is a root crop that find uses in much the same way as Irish potatoes (Onuh et al., 2004). It is grown in most part of the world and especially in the tropics where the bulk of the crops are grown and consumed. (Kochlar, 1981 and Opeke, 2006). In West Africa, sweet potato production for the year 2005 stood at 2.516 million metric tones. (FAO, 2006). Sweet potato is high in nutritional value. It outranks most carbohydrate foods in vitamins, mineral and energy content, providing over 90% of the nutrient per calorie required by most people (Watt and Merill, 1975). Sweet potato is a staple food vegetable (the fleshy roots and tender leaves), snack food, animal feed, as well as a raw material for industrial starch and alcohol. It is processed into diverse product. (Bouwkamp, 1985a; Kays, 1985; Lin et al., 1985, Sakamoto and Bouwkamp, 1985; Onuh et al., 2004).