Resistant starch analysis of commonly consumed potatoes: Content varies by cooking method and service temperature but not by variety

Abstract

Resistant starch (RS) has unique digestive and absorptive properties which may provide health benefits. We conducted a study to determine the contributions of cultivar, cooking method and service temperature on the RS contents of potatoes (Solanum tuberosum L.). We hypothesized that the RS content would vary by variety, cooking method and service temperature. Potatoes of three common commercial varieties (Yukon Gold, Dark Red Norland, and Russet Burbank) were subjected to two methods of cooking (baking or boiling) and three service temperatures: hot (65°C), chilled (4°C) and reheated (4°C for 6d; reheated to 65°C) and analyzed the starch content by modification of a commercially available assay. Results showed that RS content (g/100g) varied by cooking method and service temperature but not variety. Baked potatoes had higher RS contents than boiled; chilled potatoes had more RS than either hot or reheated. These results may assist in dietary choices for reducing chronic disease risk.