Postharvest transfer and survival of Salmonella enterica serotype enteritidis on living lettuce.

摘要

The potential for postharvest transfer of Salmonella to 'living lettuce' is not well understood. In this study, the transfer of Salmonella enterica Enteritidis (6 log CFU g-1) from worker hands or contaminated roots to leaves of living lettuce was quantified. Transfer rates of Salmonella from contaminated gloves to sequentially handled lettuce heads ranged from 94% to head 1, 82% to head 2 and 69% to head 3. On average, 2.9+or-0.1 log CFU g-1 (64%) Salmonella was transferred from inoculated roots to leaves resulting from typical postharvest handling activities for living lettuce. Salmonella persisted on leaves stored at recommended storage temperatures (4 degrees C) and increased 0.5 log CFU g-1 when stored at temperature abuse conditions (12 degrees C). Salmonella increased 1.6 log CFU g-1 on roots after 18-day storage at 12 degrees C, emphasizing the need to maintain temperature control to reduce the risk of human illness.