67B-2 |
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C. MYOJIN1, T. Yamaguchi2, H. Takamura2, and T. Matoba2. (1) Graduate School of Human Culture, Nara Women's University, Kitauoya-nishimachi, Nara, 630-8506, Japan, (2) Department of Food Science and Nutrition, Nara Women's University, Kitauoya-nishimachi, Nara, 630-8506, Japan Vegetables contain a wide variety of free radical-scavenging antioxidants such as ascorbic acid and polyphenols. Epidemiological studies have shown that vegetable consumption is associated with a reduced risk of life-style related diseases. Therefore, antioxidants in vegetables have received considerable attention in recent years for their role in human health. However, the antioxidant activity present in fresh vegetables may be affected by processing and cooking procedures prior to consumption. In this work, the changes in radical-scavenging activity of shredded vegetables during storage were determined as well as ascorbic acid and polyphenol contents. Several kinds of vegetables, such as cabbage, lettuce, bell pepper, radish, and carrot, were shredded to 1-mm width by a food processor. Then, shredded vegetables were stored at 0-10°C for 0-7 days in the presence or absence of oxygen. Radical-scavenging activity was determined by 1,1-diphenyl-2-picrylhydrazyl (DPPH)-HPLC method. Ascorbic acid and polyphenol contents were determined by HPLC and Folin-Ciocalteu methods, respectively. Effects of washing with water or sodium hypochlorite solution and drying were also examined. Radical-scavenging activity of red and green cabbage leaves remained unchanged at 10°C for 7 days in the presence and absence of oxygen. Ascorbic acid and polyphenol contents also remained for 7 days. However, flavor and appearance were better in the absence of oxygen. In other vegetables, radical-scavenging components slightly decreased in the presence of oxygen. These results demonstrate that shredded vegetables retain radical-scavenging activity and active components after 7-day storage, which indicate that shredded vegetables have the same functional value as whole vegetables.
Session 67B, Food Chemistry: Antioxidants and bioactive agents
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