Effect of temperature and chlorination of pre-washing water on shelf-life and physiological properties of ready-to-use iceberg lettuce.

摘要

Ready-to-eat lettuce is often washed with chlorinated water after cutting/shredding to destroy spoilage microorganisms, and to improve shelf life. This study shows that prewashing iceberg lettuce heads before shredding in cold and warm chlorinated water, and in non-chlorinated warm water reduced total aerobic counts, pseudomonads, and Enterobacteriaceae by 1.55-1.83 log cfu/g, which was better than a single wash of shredded lettuce. All prewashing procedures delayed lettuce browning and slowed deterioration in the appearance of packaged iceberg lettuce heads. The finding that prewashing with warm tap water is as effective as cold-water chlorination should be of particular interest to processors in countries where chlorination sanitisation of ready-to-eat foods is restricted.