This was some work done in Kazakhstan in 2019. Basically, they pumped ozone into kagats* that were covered in plastic (feet open), stored at 5 to 15 degrees. The ozone treatment was applied for 1/7 of the the time (20 minutes on, 120 minutes off), at rates of 5, 500, and 2000 mg/m3 and different molecular ion concentrations (to protect the ozone from degradation), over a period of three months. It’s not super clear if the treatment was applied to each clamp in the experiment for three months, or that the experiment was repeated continuously over three months with shorter treatment periods. I think it’s the former. The system used to pump in the ozone is a series of pipes that form a lattice at two levels of the kagat.
The results suggest ozone managed to knock out a lot of mould and yeast, but also increase sugar concentrations from 15.5% to at least 17.5%. On these numbers, it appears to be more than worth it for a farmer. It also seemed to have no negative effects from a processing point of view.
The special conditions that the beets needed to be stored under might be a bridge too far for Ozone to be adopted more broadly. It also seems to be quite toxic to humans. The levels used in this study are close to and over the limits of exposure recommended for humans (0.1ppm = 0.1g/m3 = 100 mg/m3).
*I believe this is the Russian word for “clamps”, but I’m yet to find out if we mean small on-farm piles, or large commercial at-processing-facility piles.