Abstract:The flour of the whole wheat ′Jizi 439′ was characterized in terms of the nutritional components,bioactive substances,antioxidant capacity,and starch digestibility.The results indicated that the protein content in the flour of ′Jizi 439′ was 15.31%,which was higher than that in stone-ground whole wheat flour and medium-gluten wheat flour（p<0.05）.The total dietary fiber content was 14.22%,in which the insoluble dietary fiber accounted for 91.14%.The content of total phenols,total flavonoids,and anthocyanins in the flour of the whole wheat ′Jizi 439′ was 3.03 mg GAE/g,2.48 mg RE/g,and 91.09 mg/kg,respectively,significantly higher than that in stone-ground whole wheat flour and medium-gluten wheat flour.The DPPH radical scavenging rate and hydroxyl radical scavenging rate of the flour of the whole wheat ′Jizi 439′ were 61.74%and 78.65%,respectively,indicating high antioxidant capacity.In terms of starch composition and digestibility,the flour of the whole wheat ′Jizi 439′ had a high amylose-to-amylopectin ratio of 24.28%,the rapidly digestible starch（RDS）content of 12.62%,slowly digestible starch（SDS）content of 26.51%,and resistant starch（RS）content of 70.52%.The flour of the whole wheat ′Jizi 439′ had the glycemic index（GI）of 50.44,which was significantly lower than that of stone-ground whole wheat flour and medium-gluten wheat flour,being as a low-GI food.Correlation analysis revealed a negative correlation between GI value and total phenol content（p<0.01）.In conclusion,the flour of the whole wheat ′Jizi 439′ held the potential for application in the development of low-GI foods aimed at blood glucose control.