Sequential treatment with slightly acidic electrolyzed water (SAEW) and UVC light-emitting diodes (UVC-LEDs) for decontamination of Salmonella Typhimurium on lettuce

The present study investigates a small-scale system comprising a sequential treatment with slightly acidic electrolyzed water (SAEW) washing and UVC light-emitting diodes (LEDs) for the inactivation of Salmonella on lettuce. Lettuce was inoculated with a Salmonella cocktail to achieve a final concentration of 6.67 log(10) CFU/g. Alone treatment by SAEW washing (available chlorine concentration-ACC 20-80 ppm, 1-7 min) or UVC-LED irradiation (50-200 mu W/cm(2), 1-30 min) resulted in the reduction of 1-1.8 log(10) CFU/g Salmonella on lettuce. The sequential treatment with SAEW washing and UVC-LED significantly (p < 0.05) enhance the reduction of Salmonella on lettuce to 2.56-2.97 log(10) CFU/g. The results also revealed that the sequential treatment did not result in obvious compromise in the qualities (color, chlorophyll, and total soluble solid content) of lettuce. Therefore, the proposed sequential treatment of SAEW washing and UVC-LED in this study has the potential to assure the food safety of fresh produce.

Automated summary

The study investigated a sequential treatment with SAEW washing and UVC-LED irradiation for inactivating Salmonella on lettuce. The results showed a significant reduction in Salmonella levels on lettuce without compromising its quality. This sequential treatment has the potential to ensure the food safety of fresh produce.