Pasteurising 140+ bottles twenty at a time certainly takes a while. But happily it is now all done and I just need to find somewhere to store all those bottles for the next six months or so whilst we drink the apple juice.
I need a better system for next time and I have a vague idea in my head based on some photos I’ve seen online using a large rectangular tank for a water bath. If I could find something like that (the photos show metal tanks, probably stainless steel, but I guess there’s no specific need for metal) and add some system to heat the water together with a pump and temperature sensors, all controlled by an Arduino or Raspberry Pi, perhaps that would do the job. Something like a hot water cylinder heating element might be suitable and in fact I may even have one lying around somewhere. A lid would be ideal, and perhaps insulation for the entire thing to try to reduce heat loss. Perhaps a water level sensor might be a good plan too.