Disinfection by heating is a proven and sure method for killing microorganisms in (drain) water effectively. Very recent research has shown that the ToBRFV virus in the drain water is killed off completely this way. This is a welcome development for growers who want to be protected against the growing threat of the virus. It’s also good news for growers who want to guard themselves against the growing virus threat with an Ecoster disinfector.
This research was carried out by Groen Agro Control, commissioned by the Gewascoöperatie Tomaat (Tomato Crop Cooperative), and was focused on ToBRFV (Tomato Brown Rugose Fruit Virus). In two repetitions of the experiment, after 30 seconds of heating at 95°C and after 180 seconds of heating at 85°C, the researchers were unable to detect infectious ToBRFV in contaminated drain water in the bioassay. They did find it in the control with unheated contaminated drain water, however.
During all the treatments (two repetitions), five young tomato plants were given drain water that had previously been contaminated with ToBRFV. In the two control tests with contaminated drain water without heat treatment, 5 out of 5 plants were infected with ToBRFV. The plants that were given water after heat treatment in an Ecoster disinfector remained consistently virus-free. No difference in results was observed between the heat treatments at 85°C and 95°C, although extra time was needed for the 85°C heat treatment.
A welcome development
“Our assumption that treating water with our Ecoster disinfectors also effectively renders viruses harmless has now been confirmed by an independent laboratory,” said an elated Joek van der Zeeuw. “That's reassuring for growers who are using or considering using this method. In addition, this research can put an end to any doubts about the correct treatment regimen. The two heat treatments, each of which are being applied in practice, both yield the same good results. Some growers had already switched to keeping their drain water at 95°C for three minutes. Fortunately, that turns out not to be necessary. The treatment for three minutes at 95°C does provide extra certainty to those who need it, however.”