A comparison of the kinetics of in vitro starch digestion in smooth and wrinkled peas by porcine pancreatic alpha-amylase

This study describes the impact of crop genetics and processing in two pea lines (Pisum sativum L.) on starch digestion kinetics. Mutation at the rugosus (r) locus leads to wrinkled pea seeds, a reduction in starch content and a lower extent of in vitro starch digestibility. The Logarithm of Slope (LOS) kinetic model was used to analyse digestion curves obtained using porcine pancreatic alpha-amylase for a range of particle size fractions. Changes in starch structure induced by the r mutation led to clear differences in starch digestion kinetics for purified starches and pea flours. Larger particle size fractions showed slower starch digestion relative to the purified starch, but significant differences still existed between r and wild type pea lines. It is expected that this work will help inform the design of future studies where both starch structure and food structure are important determinants of digestion behaviour.