I spent my childhood doing canoe trips with my family out on rivers and lakes, and I can say that all the advice given here is all in line with the rules I was taught. Keep food and food smells away from your tent, burn empty cans of tuna or whatever in the fire to take care of the smell in the can, the idea of using one pannier (or canoe pack, or backpack or whatever) for food and hanging up in a tree makes sense.
ACTUALLY: There have been some changes: burning anything other that locally-sourced-wood in a campfire is not considered appropriate back-country behavior. All man-made-material that's been carried-in should be stored properly before & after use. It should then be carried out!
BTW: As far as I'm concerned you shouldn't even do any backcountry-campfires. Keep that nostalgia for fire pits in developed campsites with fire-rings.
ADDTIONAL POINT: Burning a tuna can will probably permeate a more attractant odor for a much larger area, so it's probably counterproductive to the goal of not attracting bears.