Zucchinis, cucumbers, green bell peppers, and root vegetables such as potatoes, sweet potatoes, carrots, and radishes, which are the most common vegetables used in school foodservice (18 ), were purchased from a wholesale market in Seoul, Korea. The items were transported to the laboratory and processed within an hour according to the pre-processing steps (Fig. 1). Each produce item was prewashed with regular tap water to remove dirt, followed by cutting and peeling. After the trimming steps, the fresh produce underwent three washing steps. The primary step was a washing with tap water (10°C) for 3 min. The second step was washing with two sanitizer solutions (10°C) for 5 min with either (a) 100 mg/L sodium hypochlorite (SH, pH 6.5~7.0) (Doctorchlo Q, Hansonhigen, Chungnam, Korea) or (b) 500 mg/L acidified sodium chlorite (ASC, pH 2.5~2.9). The 100 mg/L sodium hypochlorite was used according to the school foodservice hygiene guidelines (19 ). The ASC was prepared by mixing sodium chlorite (Kanto Chemical Co. Inc., Tokyo, Japan) and citric acid at a 50:50 (w/w) ratio (Duksan Pharmaceutical Co. Ltd., Gyeoggido, Korea) (20 ). The final washing step used tap water (10°C) for 5 min to reduce chlorine odor. The ratio of sample to washing water was 1:10 (w/v). After washing, the washed produce was sliced (2.0×2.0×1.0 cm) automatically with a vegetable cutter (H.M.V-200, Hwa-Jin junggong™, Gyeoggi, Korea). The sliced produce was drained for 10 min using an aseptic basket. The drained fresh-cut produce was vacuum packaged in PE (poly-ethylene) bags using a vacuum packaging machine (IS-100, Zeropack, Gyeoggi, Korea). All samples were stored at 4°C and 10°C. Microbial and chemical analyses of samples were performed during 5~12 days of storage, according to the characteristics of fresh-cut produce and the results of preliminary studies (21 –23 ).