Impact of different cooking methods on the chemical profile of orange-fleshed sweet potato (Ipomoea batatas L.)

Abstract

Orange-fleshed sweet potato (OFSP) has attracted increasing attention due to its high carotenoid levels, which is beneficial to human health. However, the changes in the chemical composition of OFSP after cooking are not fully elucidated yet. In this study, the contents of starch, soluble sugar, carotenoids, volatile compounds, and metabolites of OFSP before and after cooking (steaming, boiling, and baking) were determined to evaluate the changes in its flavor and chemical composition. After cooking, the contents of starch decreased from 18.15% to 7%, and soluble sugar increased from 11.78% to 39.33%. The baked OFSP was the sweetest one due to the production of most sugars during baking. Additionally, the aroma of baked OFSP was the best due to the abundance of furans, aldehydes, ketones, and monoterpenes, including 6 volatiles produced by carotenoids. However, the steamed OFSP retained more carotenoids, while all carotenoids were reduced 7%–23% after cooking. Furthermore, 593 metabolites were identified in OFSP, of which 82.5% were well preserved after cooking. Overall, understanding of chemical profile changes of OFSP after cooking will provide a theoretical basis for broadening sweet potato processing and application.