We hide fruit etc. in Mom's room for her but now Dad eats most or all of the yogurt, cheese, lunchment, eggs etc. in the regrig. even if we freeze some, or try to hide food in paper bags or behind other things in refrig. She can't eat just frozen dinners from microwzve for every meal.
I agree that it is perhaps time to reevaluate their living arrangements.
Another thought is that he could go the adult day care to give her a break and occupy him with something other than eating.
I must be missing something. My solution seems so obvious. Buy more food.