Why look for MuckDonalds when you can sample the local fare at many of these airports ? I'm guessing that if you're in an airport where you want to avoid the local food for hygiene reasons, these truly international restaurant chains won't be there anyway.
When you arrive at an airport, you've probably been fed recently (in the aircraft), so why not do a bit of recce'ing ? Then, you can decide if you'd be better off with a meal *before* you arrive at the airport on the outbound flight.
Of course, Japanese McDonalds have delightful local variations which you can't get elsewhere ... their wasabi chicken burger is very tasty