Karntarat WuttiselaSujin ShobsngobWannapong TriampoDarapond TriampoMahidol University2018-07-122018-07-122008-01-01Journal of the Chilean Chemical Society. Vol.53, No.3 (2008), 1565-156707179707071793242-s2.0-54949125657https://repository.li.mahidol.ac.th/handle/123456789/19099Analysis of the shift of wavelength maximum using a rapid colorimetric method was used to determine the ratio of amylose:amylopectin (Am:Ap) in acid-hydrolyzed tapioca starch. The absorbance maximum of 600 nm (Am:Ap of tapioca starch ≈22:78) moved to shorter wavelengths (590, 585, 570, 560, and 534 nm) as the decrease of the Am:Ap ratio due to hydrolysis of shorter chains that are not be able to form a complex with iodine. The amount of amylopectin itself may be unaltered or slightly decreased but the decrease in amylose caused a decrease in Am:Ap ratio.Mahidol UniversityChemistryArticleSCOPUS10.4067/S0717-97072008000300002