Author(s)

Ateea A. Bellail, Omayma E. Shaltout, Mohammed M. Youssef, Ahmed M. A. El Gamal

Food Science Department, Faculty of Agriculture (Saba-Basha), Alexandria University, Alexandria, Egypt.
Food Technology Department, Faculty of Agriculture (El-Shatby), Alexandria University, Alexandria, Egypt.
Plant Production Department, Faculty of Agriculture (Saba-Bacha), Alexandria University, Alexandria, Egypt..

Four sweetpotato (Ipomoea batatas (L.) Lam.) cultivars grown in Alexandria, Egypt, including Monofya 6, Monofya 66, Abeeis, and Beauregard were cooked using four different home-cooking methods (boiling, baking, microwaving, and deep-frying). The antioxidant contents (total phenolics by Folin-Denis, and individual phenolic acids by HPLC) as well as the antioxidant activity determined by reducing power (RP), 2,2-diphenyl-1-picrylhydrazyl (DPPH), and 2,2’-azinobis(3-ethyl-benzothiazoline-6-sulfonic acid) (ABTS) were measured in this study. Results indicated that total phenolic contents of raw flesh tissue by Folin-Denis ranged from 0.53 to 0.87 mg chlorogenic acid equivalent (mg ChAE)/g dry weight basis (dw). The RP ranged between 0.1 and 0.25 mg ChAE/g dw, DPPH and ABTS radical scavenging activities varied from 1.10 to 1.72 and 0.85 to 1.51 μmol trolox equivalent (TE)/g dw, respectively. Thermal processing significantly (P ≤ 0.05) increased the total phenolic content, as well as individual phenolic acids and antioxidant capacity of all the cultivars under study. In this respect, deep-frying exhibited the highest increment among the four processing methods. The most abundant individual phenolic acids in processed flesh roots tissues were chlorogenic acid followed by 3,5-dicaffeoylquinic acid. Total phenolic contents were highly correlated with RP, DPPH, and ABTS, also the correlation between the DPPH and ABTS values were significantly high.

Sweetpotato; Total Phenolics; Antioxidant Activity; Chlorogenic Acid; Thermal Processing; HPLC

A. Bellail, O. Shaltout, M. Youssef and A. Gamal, "Effect of Home-Cooking Methods on Phenolic Composition and Antioxidant Activity of Sweetpotato (Ipomoea batatas (L.) Lam.) Cultivars Grown in Egypt," Food and Nutrition Sciences, Vol. 3 No. 4, 2012, pp. 490-499. doi: 10.4236/fns.2012.34069.