For Abstracts

Hetong Lin (College of Food Science, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China); Yihui Chen (College of Food Science, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China); Yen-Con Hung (Department of Food Science and Technology, University of Georgia, 1109 Experiment Street, Griffin, GA 30223, USA); Yifen Lin (College of Food Science, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China); Meirong Fan (College of Food Science, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China)

In order to evaluate the possibility of heat treatment prior to cutting for maintaining quality and increasing storability of fresh-cut Chinese yam (Dioscorea opposita Thunb.), fresh tubers cv. Shangehuaishan No.1 were washed with tap water to remove soil and other foreign matter, dipped in 200 mg/L chlorine hypochlorite for 10 minutes to surface-sterilize, treated with hot-water at 35, 40, 45 degrees C for 30 min, then peeled and cut into approximately 30-mm blocks. The cut yams were rinsed with distilled water, then air-dried and packed into sealed polyethylene bags (0.015 mm thickness) and stored at 4 degrees C for 10 days. At 2-day intervals, the CIE (Commission Internationale de L'Eclairage) parameter of L*, the browning index, the value of browning degree, polyphenol oxidase (PPO) activity, weight loss, total sugars and respiration rate were determined. The results showed that compared to the untreated hot-water yam samples, hot-water (35, 40, 45 degrees C) treatment exhibited significantly higher L* values, lower browning index, lower PPO activity, lower weight loss and lower respiration rate, and higher contents of total sugars. Among the hot-water-treated yam samples, hot-water at 45 degrees C for 30 min was the most effective treatment in maintaining quality and increasing storability. These results indicate that the hot-water treatment at 45 degrees C for 30 min prior to cutting might be a feasible technique for maintaining quality and increasing storability of fresh-cut Chinese yam during storage at 4 degrees C.