Effects of jupcheong (soaking in syrup) with ginger powder on the lipid oxidation and antioxidant stability of yakgwa (Korean deep-fried confection)

Abstract

This study evaluated the effect of jupcheong (soaking in syrup) with/without ginger on lipids and antioxidants of yakgwa (Korean deep-fried confection) during storage. Yakgwa was prepared with a dough consisting of wheat and rice flour (1:1, w/w), sesame oil, and sugar syrup. Shaped dough pieces were consecutively deep-fried in soybean oil at 90 and 150 degrees C, soaked in syrup with/without ginger powder, and stored at 30 degrees C in the dark for 8weeks. Lipid oxidation was evaluated by peroxide and p-anisidine values, and antioxidants were determined spectrophotometrically. Jupcheong reduced lipid oxidation and antioxidant degradation during yakgwa storage, and increased stability by jupcheong was higher in lignans or tocopherols than polyphenols. The results suggest that jupcheong especially with ginger could improve the lipid oxidative stability of yakgwa by higher protection of tocopherols and lignans than polyphenols from degradation, and tocopherols were the most important antioxidants in reducing lipid oxidation of yakgwa.