Cryo-SEM to characterize the Microstructure of Starch during in vitro digestion

Session

Cryo-Electron Microscopy

Authors

Dr Mark Taylor (1)

Affiliations

1. Quorum Technologies

Keywords

Cryo-SEM, Starch, Microstructure, In vitro, Glucose and Fermentation

Abstract text

Starch is the main carbohydrate in human nutrition, which can be classified, in terms of digestibility as Resistant Starch (RS), Slow Digestible Starch (SDS), and Rapidly Digestible Starch (RDS). RS is classified as a prebiotic as it is a vital source of fuel for good gut bacteria. During fermentation, this prebiotic produces short-chain fatty acid butyrate as a by-product helping to protect the gut cells in the process. SDS in comparison to RDS offers the advantage of slow-release postprandial glucose levels, lower Glycemic Index (GI), and a reduced risk of diabetes and cardiovascular disease.

The aim of this study was to study the in vitro digestibility of starch from different cultivars and foods, cooked and uncooked accompanied by the microstructural changes occurring during simulated gastric and small intestinal digestion. Cryo-SEM was used as this was able to immobilize the process in its natural digest state. The extent of starch hydrolysis varied according to cultivar and food type.

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