Tapioca or cassava is one of the most important crops of Thailand.The availability of roots supplied to the starch industry is all year round.At present,there are 1.3 million hectares devoted to tapioca planting,producing about 30 million tons of roots.[1] The tapioca root has a high starch content.They are recognized as an excellent source of pure starch suitable for a wide range of applications.The most important characteristics of tapioca starch are odorless,paste clarity and stickiness,which are remarkable characteristics of tapioca starch for the food industry.[2] However,native starch has quite a few shortcomings for food industrial applications such as insolubility in cold water,loss of viscosity,and thickening power after cooking.[3] These shortcomings of native starch could be improved by different modification techniques which include chemical or physical routes.