I found this online:
How long will the food in my refrigerator or freezer keep during a power failure ?
Hydro-Qu颥c - Residential Customers
Your food will keep 24 to 48 hours, provided that you open the refrigerator and freezer door as little as possible. However, once the food in your freezer has thawed you should eat it as soon as possible, and avoid refreezing it. Plug your equipment into a power bar with a surge protector, available in any good hardware store. Also, avoid plugging electronic equipment into the same circuit as powerful motor-driven appliances, such as a dishwasher, air conditioner or refrigerator.
Chris