Army waterproof bags hold about 40-45 lbs and tie the top off as customary, done properly they are cheap dry bags.
Bear proof containers are tested with bears, the put food inside and smear honey all over the container, that gets them interested, an hour later if the bear has success, the product fails the test. They won't test containers with sharp edges or locking devices as the bear may be injured. A bear cab rip off a car door or open a sealed can, so I doubt any bag is bear proof.
They can smell the food, best is to hang it in a tree as shown on bear safety sites. Unattended vehicles better be clean inside, like those two french fries you dropped between the seats last week.
I'm still training my Boxer, she better obey in bear country, I don't want her trying to take any wild animal on, much less a bear. A Boxer isn't a great scent dog but she can find her toys regardless of where I hide them.
Can't hide the scent, just make it hard to get to it, bears don't carry ladders.
I have inquired about spraying the outside of things with bear spray, those who know that smell may stay away, don't know.
