Lotus root, dried laver, and perilla leaf bugak, Korean traditional fried cuisine, were prepared with fermented glutinous rice batter and unroasted sesame oil or wheat flour batter and soybean oil and their physicochemical characteristics was evaluated. Bugak with fermented glutinous rice batter and unroasted sesame oil showed higher hardness, possibly brittleness than bugak with wheat flour batter and soybean oil. Oil absorption was higher in bugak with fermented glutinous rice batter and unroasted sesame oil than bugak with wheat flour batter and soybean oil, however, the lipid oxidation, evaluated by conjugated dienoic acid and p-anisidine values, was significantly lower in bugak with fermented glutinous rice batter and unroasted sesame oil. Frying oil strongly influenced the degree of lipid oxidation and fatty acid composition of bugak lipid. Different preparation of bugak did not show great effects on the contents of chlorophylls and carotenoids of dried laver and perilla leaf bugak, possibly due to protection by rice or wheat flour batter coating.

In vitro antioxidative activities and antioxidants of the lotus root, dried laver, and perilla leaf bugak, Korean traditional fried cuisine, were evaluated. The bugak was prepared with fermented glutinous rice batter and unroasted sesame oil for use in the pan-frying. The perilla leaf bugak showed the highest radical scavenging activity and reducing power, with the lowest in the lotus root bugak. The antioxidative activity of the blanched lotus root was lower than the dried laver or the perilla leaf. Polyphenol content was higher in the perilla leaf bugak than the lotus root or the dried laver bugak, and tocopherols were mainly derived from frying oil. The antioxidative activity of bugak was correlated well with polyphenol contents, but there was no correlation between tocopherol contents and the antioxidative activity.

No abstract

This study investigated the effects of the addition of gardenia seed, green tea, or cactus pear () to rice batter at 10% on the lipid oxidation, pigments, antioxidants, and antioxidant activity of lotus root and frying oil. Lipid oxidation was evaluated based on the conjugated dienoic acid and-anisidine values. Lipid oxidation and tocopherol degradation were significantly reduced in the gardenia seed-added and frying oil, whereas the cactus pear-added and frying oil showed an increase. The addition of green tea had no significant effects on the lipid oxidation of and frying oil. The antioxidant activity of lotus root significantly increased with the addition of gardenia seed, green tea, or cactus pear. The results suggested that green tea and gardenia seed could improve the health and food functionality of antioxidation for lotus root, respectively.

The effect of frying oil on the lipid oxidation, antioxidants, and in vitro antioxidant activity of gim bugak was studied. Bugak was prepared by pan-frying at 180 °C in unroasted sesame, soybean, extra virgin olive, or palm oil. The degree of lipid oxidation based on conjugated dienoic acid and -anisidine values was higher in the bugak fried in soybean or sesame oil with high contents of polyunsaturated fatty acids and tocopherols. However, the oil oxidation was lower in olive and palm oils, which showed higher degradation of tocopherols and polyphenols than in sesame or soybean oil during frying. Although the bugak fried in palm oil contained less antioxidants than that fried in soybean or sesame oil, the in vitro antioxidant activity was not different ( > 0.05). Results suggest that palm oil can replace unroasted sesame oil for the preparation of gim bugak with improved lipid oxidative stability and health functionality.