Evaporator temperature switch

I don't know why not. The "if" would be finding out what the design temp should be, or maybe an industrial one. Cap tube, or tube and bulb temp controls of all kinds used to be very very available in the commercial HVAC/R industry, at least back before electronic sensors became more common.

The starting place, of course would be 32F. But airflow may allow that temp to be dropped somewhat

Make sure you get one "open on temp drop" That is, like the normal operation of a fridge / freezer control.