Cereals & Grains Association
Log In

Effects of the amount and type of fatty acid on the in-vitro starch digestibility and expected glycemic index of millet starch
G. A. ANNOR (1), M. Marcone (1), M. Corredig (1), E. Bertoft (1), K. Seetharaman (1). (1) University of Guelph, Guelph, ON, Canada

This study investigated whether the amounts and types of fatty acids present in millets played any role in their hypoglycemic property. The first part of the study consisted of complexing cooked pearl, finger, proso and foxtail millets with palmitic, oleic, linoleic and elaidic acid in the amounts present in their respective millet flours. The second part involved complexing the same amount (2 mmol/g of starch) of these fatty acids to the millet starches and subjecting the complexes in both parts of the study to in-vitro starch digestibility and calculating their expected glycemic index (eGI). The complex index (CI) of the fatty acids was also determined. The CI of the fatty acids increased with increasing unsaturation. Significant (p<0.05) reductions in the in- vitro starch digestibility and eGI of the millet starch-fatty acid complexes was observed. Reductions in the starch hydrolysis of the samples were significantly linked to the amounts of the fatty acids added. The addition of 2.29 mg palmitic acid and 23.8 mg linoleic acid/g of proso millet starch resulted in expected glycemic index of 63.6 and 53.1 respectively. Unsaturated fatty acids generally resulted in less starch being hydrolyzed. Oleic acid was the most effected in reducing the amount of starch hydrolyzed resulting in the decrease in the eGI of finger millet starch from 65.4 to 51.3 when 2 mmol/g of starch of oleic acid was added. Linoleic acid however resulted in slightly more starch being hydrolyzed as seen with trans oleic acid compared to the cis configuration. The amount and type of fatty acids therefore played a significant role in the hypoglycemic property of millet.

View Presentation