Puddings are thickened with starches such as corn starch or tapioca. Starch is extracted from cassava/tapioca. Isoamylase was found to saccharify potato starch, arrow root, tamarind kernel, tapioca, and oat. Prawn crackers are made by mixing prawns, tapioca flour and water. Rice is the staple food supplemented by millet maize and tapioca. Cassava is also the main ingredient in tapioca pudding. They also eat millet, maize, tapioca etc. In the north, fillings are mostly red bean paste and tapioca or taro. Other crops include coconuts, corn, rubber, soybeans, sugarcane and tapioca. The primary agricultural products include limited amounts of maize, beans, cassava (tapioca) and citrus fruits. The most common krupuk is "kerupuk kampung" or "kerupuk aci" made of tapioca starch. Rice is grown in abundance along with tapioca. Lumping of tapioca pearls can be avoided by stirring and adding sugar. As a result, cassava (tapioca) chips have gradually become a major source of ethanol production. Cassava is referred to as Tapioca in Indian English usage.