Comparative Assessment of Carotenoid and Polyphenol Contents, and Antioxidant Capacity in Thermally Processed Starchy Crops

The evaluation of health‐promoting compounds in starchy crops remains a relatively unexplored area of research. This study investigated the impact of cooking methods (control, boiling, and baking) on crop part (whole, flesh, and skin) of sweet potato, cocoyam, and Irish potato. On a fresh weight (FW) basis, boiled sweet potato flesh showed the highest α‐carotene content, while baked flesh had the highest β‐carotene content. Lutein was detected only in Irish potato, with higher content in the skin. The skin of all three starchy crops exhibited the highest total phenolic and total flavonoid contents ranging from 12.63 to 83.46 mg GAE/g FW and 1.12–4.64 mg RE/g FW, respectively. The three different assays used to assess antioxidant capacity presented higher values for cocoyam skin (ferric reducing antioxidant power = 125.15 mM Fe 2+ /g FW), sweet potato skin (Trolox equivalent antioxidant capacity = 127.69 mM TE/g FW), and whole uncooked sweet potato (2,2‐diphenyl‐1‐picrylhydrazyl inhibition = 94.73% FW). Multivariate analysis was employed to study patterns, distributions, and relationships. These findings suggest that the content and composition of carotenoids, polyphenols, and antioxidant activity in sweet potato, cocoyam, and Irish potato are impacted by cooking method.