Application of an innovative water-assisted ultraviolet C light technology for the inactivation of microorganisms in tomato processing industries

Abstract

We aimed to study the efficacy of a water-assisted UVC light device (WUVC) as an innovative clean technology for the disinfection of fresh sound tomatoes and processing wash water and water turbidity was evaluated as a critical parameter. First, wash waters with different turbidities (from 0.4 to 828 NTU) were inoculated with Listeria innocua and treated in the WUVC device at different dosages. Secondly, fresh tomatoes, inoculated with L. innocua and non-inoculated ones, were treated using the WUVC device containing wash water of different turbidities for different times. The reduction of L. innocua populations on wash water and on the surface of tomato was influenced by turbidity; lower reduction values were observed at higher turbidities.Washing tomatoes with tap water with UVC lamps off (control treatment, TW) decreased L. innocua population on the surface of tomatoes but did not eliminate those bacteria that went into the water. Contrarily, when UVC lights were on, L. innocua population in wash water after treatment significantly decreased, those in clean water being the lowest populations. Reductions of native microbiota on the clean water treated with the highest UV-C radiation dose were lower than those obtained when tomatoes were artificially inoculated. We demonstrated that high reductions of L. innocua population on fresh tomatoes could be achieved using the WUVC system but some drawbacks related to the increase of turbidity should be solved for its implementation in real conditions.

An innovative water-assisted UV-C disinfection system to improve the safety of strawberries frozen under cryogenic conditions

“…For this reason, the incorporation of water to the treatment enhanced the efficacy of this innovative technology. Turbidity of the wash water used could affect UV-C penetration (Abadias et al, 2021) and to extend exposure times for better UV-C efficacy may not be realistic and should be further studied. Successful application of this combined technology relies on the light reaching all the virus particles directly and, if the viruses are present in cracks, crevices or openings in the surface of the food or surfaces, they could be inactivated with the chemical sanitizer present in the water.…”

Effect of Surface Structure on the Sensitivity of Fluorescence-Enhanced Si Photodiodes for Ultraviolet C Light Measurement

“…UVC light is characterized by shorter wavelengths and higher energy, in addition to its strong bactericidal effect on viruses and bacteria. [2][3][4][5][6]8,9,18,19,[21][22][23] The efficiency and safety of UVC-LEDs, which emit UVC light without using hazardous substances such as Hg, have garnered significant interest because of their compact size, low energy consumption, and longevity.…”