Effect of Calcinated Calcium Washing Solution and Heat Treatment on Quality and Microbial Reduction of Fresh-Cut Lettuce and Broccoli

Compared with chlorine (50 mu l L-1) washing, calcinated calcium (CC, 1.5 g L-1) alone or in combination with heat treatment (45 degrees C for 2 min) were investigated as potential sanitising treatments for fresh-cut iceberg lettuce and broccoli. Samples of fresh-cut lettuce and broccoli were packaged in 80 mu m nylon/polyethylene (PE) and 50 mu m PE bags, respectively and quality parameters monitored during storage at 5 degrees C. Results revealed that washing in CC at normal water temperature was effective as effective as chlorine in reducing microbial populations in both the vegetables. Washing with CC combined with heat treatments increased an electrical conductivity of fresh-cut lettuce and broccoli tissue. Combined heat treatment with washing solutions reduced aerobic plate count on fresh-cut lettuce and broccoli only in initial period of storage. Later in storage, heat treatment induced injury of fresh-cut leafy vegetables. However, samples treated with CC had good quality with low off-odor at the end of storage. Thus, CC at normal water temperatures, an environment-friendly sanitizer, is an alternative to chlorine for washing of fresh-cut leafy vegetables.