Abstract :
Studying starch amylolysis kinetics in vitro is valuable for predicting the postprandial glycaemic response to
starch intake. Prediction of starch amylolysis behaviour is challenging however, because of the many
physico-chemical factors which influence amylolysis. The Logarithm of Slope (LOS) method for analysis
of digestibility curves using first-order enzyme kinetics can identify and quantify nutritionally important
starch fractions. The early stages of in vitro amylolysis of hydrothermally processed chickpea and durum
wheat with variable degrees of structural integrity were studied. The end-point product concentration
(CN) and the pseudo first-order digestibility rate constant k, obtained from LOS analysis, were then used
to compute predictive digestibility curves for evaluation of the model performance. LOS analysis enabled
rapid identification of nutritionally important starch-fractions. It was clear that purified starches and
flours were digested by a single-phase process, but starch amylolysis in macroparticles occurred by a
two-phase system that reflected differences in substrate accessibility. The model gave an excellent fit to
data obtained from a range of heterogeneous materials. It provides a rigorous means of studying the
mechanisms of starch amylolysis in samples of varying complexity, and we strongly recommend its use
for the rapid and accurate predictions of amylolysis. Such predictions have implications for prevention
and management of type 2 diabetes mellitus and obesity.
Title of Article :
A novel method for classifying starch digestion by modelling the amylolysis of plant foods using first-order enzyme kinetic principles
Author/Authors :
Edwards, Cathrina H. , Warren, Frederick J. , Milligan, Peter J. , Butterworth, Peter J. , Ellis, Peter R.
Author/Authors - جزئيات :