I think the whole topic is sorta bogus. Beet juice, like virtually every other material in the universe, will freeze, and it will freeze solid. The question should really be at what temperature it freezes, how does it behave as the temperature drops, and will I ever see that temperature where I use my tractor.
If it doesn't freeze until -45 F, most of us won't care (AKwelder excepted). Wind chill will not affect this, only the temp.
I did have to work in -56 once back in 1983, but there was no way we could get the tractor to turn over, muchless start, so frozen fluid in the tires was not a concern.