Effect of slightly acidic electrolyzed water (SAEW) and ultraviolet light illumination pretreatment on microflora inactivation of coriander

摘要

Microbiological contamination of vegetables leading to foodborne disease is a serious public health problem. Slightly acidic electrolyzed water (SAEW) and ultraviolet-light emitting diode (UV-LED) are considered to have good bactericidal effect. However, the limitations of SAEW in application include its instability and the great dependence on equipment and that of UV-LED remains poorly characterized. To improve decontamination efficiency and explore the combined bactericidal efficacy, the coriander, immerged in different concentration SAEW in advance, were studied under various UV-LED intensity: 80, 160, 240 mu W/cm2 for different times. Additionally, the coriander was evaluated for total viable counts and general quality. The result showed that UVLED-SAEW combined treatment has better decontamination efficiency than that of single factor and the inactivation efficacy was related to the concentration of SAEW, intensity of UV-LED and their treating time. The 240 mu W/cm(2) UV-LED irradiation for 30 min combined with SAEW (ACC of 60 mg/L) 5-min-washing led to 2.72 log CFU/g Salmonella reduction and 2.42 log CFU/g E. coli reduction. The SAEW and UV-LED treatment cause no significant negative effect on overall coriander quality and prolonged the shelf-life of coriander. UV-LED with SAEW pretreatment shows potential for reducing foodborne pathogens on coriander without effects on its quality.