Evaluation of physical properties, functional components, and starch digestibility of dumpling skins made from barley flour with various amounts of β-glucan

This study aimed to evaluate the physical properties, functional components and starch digestibility of dumpling skins made from barley flour with various amounts of beta-glucan (cv. Sachiho Golden, Mochikinuka, and Daishimochi). Barley dumpling skins were prepared by mixing 60 g of barley flour, 40 g of wheat flour, and 65 ml of ultrapure water, kneaded, shaped, and cooked. Wheat dumpling skins were also prepared and used for comparison. beta-glucan content in the cooked skins was the highest in Daishimochi (2.2 % db), while total polyphenol content was the highest in Daishimochi (2.0 % db). Cooked skins showed that Mochikinuka (2.4 N) and Daishimochi (2.4 N) had the lowest firmness, and Daishimochi (7.7 mm) had the shortest extension. Starch digestibility differed among the cooked skins, and estimated glycemic index was highest for Mochikinuka (127.7) and lowest for Sachiho Golden (94.4). Equilibrium percentage of starch hydrolysis was negatively correlated with the apparent amylose content (r = -0.99,p < 0.01) and resistant starch content (r = -0.98,p < 0.05). beta-glucan content in the cooked skin did not correlate with firmness, extension, apparent viscosity, and starch digestibility, indicating that it may have indirectly affected these properties.