The in vitro digestion rate and in vivo digestibility of raw starches from selected cereals and tubers

The present study was conducted to evaluate the in vitro digestion rate and the in vivo digestibility of raw starches from selected cereals and tubers. Cereal starches with lower resistant starch content were easier to be digested than tuber starches. The rapid digestible starch levels in glutinous rice and oat were high and the proportions of which were 40.17% and 83.88%, respectively. The slowly digestible starch contents in cereals, Chinese yam and Chinese cassava were higher than 45.70%. The in vitro digestion of the selected raw flours increased along with the extension of incubation time, and more than 66.55% of which (except for that of taro and potato) was digested when the incubation time was extended to 6 hours. The jejunum is an important organ for the digestion and absorption of starch, and more than half of the starches in different selected flours (except for that of taro, potato and Chinese yam) was digested in distal jejunum. The digestibility of most of the selected flours, that were incubated for 6 hours, was close to the digestibility of these starches in the distal ileum of pigs.