How do you figure the average cost for food in a nursing home?

My father is paying $185 per day to live in a nursing home. I spoke with the director of dietary services and he said the amount budgeted per resident for food per day (3 meals and a snack) is $5.20! I checked it out and this is the same as the weekly food stamp allowance for a male over 71 years old. You could try asking the director of dietary services what their budget is. I suspect most nursing homes' food budgets are equally as grim.