Cooking Methods Altered the Microstructure and Digestibility of the Potato.

In order to investigate the microstructure and digestibility changes of the potato processed with different cooking methods, potatoes are cooked by boiling, deep‐fat frying, or Chinese stir frying. The microstructure changes and starch digestibility of the cooked potato are observed using scanning electron microscopy as well as a simulated gastro‐small intestinal in vitro digestion model. Portions of cooked potatoes are also served to human to study the digestion of potatoes in vivo. Results indicated that the cooked potatoes were minimally hydrolyzed in a simulated stomach while increased significantly during the small intestinal simulation. The equilibrium starch hydrolysis is 82.21% (boiling), 68.19% (stir‐frying), and 53.45% (frying), respectively. The starch granules swells and connects with each other after boiling, whereas mud‐like surfaces are observed after stir‐frying and oil‐immersed and compact surfaces are observed after frying. In vivo study indicates that the fried and stir‐fried potato showed a lower glycemic index (GI) than that of the boiled potatoes, which are 74 ± 6, 69 ± 5, and 103 ± 6, respectively. Our results indicates that the digestibility of potato may be influenced by the modification/destruction of the microstructures during domestic cooking; Chinese stir‐frying could be suggested as an alternative cooking method to slow down its digestibility. [ABSTRACT FROM AUTHOR]