Development of Washing and Sterilization System for Leafy Vegetables

To ensure food safety of leafy vegetables such as lettuce, Perilla, and flat Chinese cabbage, various microorganisms and foreign materials commonly found on the leaf surfaces must be removed or inactivated by sterilization before these the food is consumed, especially when served in large restaurants or school cafeterias. This study was conducted to develop a washing and sterilization system for leafy vegetables. Results showed that the optimum washing times using air bubbles for lettuce and Perilla was five minutes and for flat Chinese cabbage was ten minutes. The percentage of bacteria removed after the optimum washing times were 94, 98, and 76% for lettuce, Perilla, and flat Chinese, respectively. The system was developed so that leafy vegetables contained in a box were continuously moved to pass through the washing, sterilization, and dehydration stages.