If you switch a refrigerator off, how long is it safe to keep the food in there, say, if it was a restaurant?!
Answers:
There is no definite answer because it depends on how long it takes for the temperature inside to rise above the safety limit. The fuller a refrigerator is, whether commercial or home, the longer it takes for temperature to rise because the there is less air inside which does not hold a lot of coldness. Therefore it is always advisable that when a refrigerator or freezer is too empty, you should stock it up with something like bottles of water. Should the power goes off the cold items can keep each other cold for longer time.
That said, even if it's full, I don't think you should switch it off for more than 1 hour in order to be safe.
Well if its a restaurant or industrial deep freezer that is kept closed they can stay at frigged levels for 12-15 hours, but in most cases by law if the freezer is not running the food has to be moved to a working freezer because of potential health code violations.
Until the temperature rises above safe limits, which in the US would be below 5 degrees C for most foods. Most inspectors would gig you for having food in a non-functional refrigerator, temperature wouldn't matter.
Please do not do that at a restaurant...
Think of the potential damage to the business.
Maybe 30 minute as long as closed, must a Temperature of less than 50 degrees.