Abstract: In this study, the amylose contents in 24 commercial foxtail millet samples from major production provinces in China were determined by four different methods, namely, the improved national standard method (GB/T 15683-2008), the spectrophotometric method (NY/T 2639-2014) recommended by China’s agricultural authority, the dual-wavelength method, and the concanavalin A (Con A) method. The results of these methods were in the following decreasing order: improved GB/T 15683-2008 ≈ dual-wavelength > NY/T 2639-2014 > Con A. The correlation coefficient between the results of improved GB/T 15683-2008 and those of NY/T 2639-2014 was highest, 0.752 (P = 0), the former being about 1.41 times higher than the latter, which could allow simple prediction of the amylose content of foxtail millet. In conclusion, the improved GB/T 15683-2008 method, the dual-wavelength method and the NY/T 2639-2014 (× 1.41) method can be used to accurately determine the content of amylose in foxtail millet while greatly reducing sample testing time.

Key words: foxtail millet; amylose content; colorimetry; dual-wavelength method; concanavalin A