I would say that the key to eating healthy and well on canoe trips is owning a dehydrator.  For a relatively small initial cost you can decide for yourself the quality of the food you eat.  I prefer to eat organically and locally grown foods and with a dehydrator I can do both and take meals that are delicious, nutrious and lightweight.  My wife and I like to eat well and on our 3 week trips it's gourmet all the way with chilis, stews, borschts and soups, re-fried beans and dozens of other dishes, not to mention all sorts of fruits and vegetables dried fresh and in season.  Of course this is all boosted with fresh fish and berries.  We also take a variety of peas and beans that we sprout as we go for something truly fresh.  With a dehydrator you can completely get away from processed foods and all that freeze dried crap which tends to be flush with preservatives and more often than not, foul tasting to boot.  By the way, if you really want to get into it try using a reflector oven.  We took one with us for the first time last summer and it was sooooo cool - date nut loaf, corn bread, home made chocolate brownies (no package mixes for us!) - mmmmmm!  The only things we don't bring are table cloths, candelabra and a roving violinist to set the mood (we'll just have to be satisfied with loons and wolves, I guess.)