Abstract: | A novel triple‐wavelength colorimetry based on the principle of iodine binding was developed to determine amylose and amylopectin contents. Detection wavelengths of different starch material were different for each method. Comparative trials were carried out by both single‐ and dual‐wavelength colorimetry. We found that single‐wavelength colorimetry could only be used to evaluate amylose content. Correlation coefficient of standard curves for amylopectin content determination was improved by increase of detection wavelength numbers. The precision and recovery coefficient was also improved by triple‐wavelength colorimetry compared to single‐ and dual‐wavelength colorimetry. Percent amylose of cassava, potato, and high‐amylose maize determined by triple‐wavelength were 19.3, 21.8, and 42.3%, respectively, and percent amylopectin were 78.9, 76.9, and 54.5%, respectively. This developed triple‐wavelength colorimetry could provide accurate data for evaluating amylose content and have potential for amylopectin content detection. |