UDAP, the folks that make pepper spray for fending off bears, also offer (of all things) an electric fence as an alternative to hanging food in bear country. Powered by 4 D -cell and 4 AA batteries the fence packs a 7600 volt punch into a 9 pound package.
Looks like a viable alternative for groups that spend a lot of time in serious bear country. We hang our food when we are canoeing in Canada more to protect it from other animals than the black bears found in Algonquin (never spotted one myself).
Here’s a video of research conducted by the National Outdoor Leadership School (NOLS)
NOLS has used mesh electric fences for food storage since 2004, with over 100,000 fence-nights in bear habitat. This testing in 2002 was done to meet testing requirements that got the food storage fence approved by the Interagency Grizzly Bear Committee (IGBC).
I was a beekeeper for several years and used a solar powered electric fence to protect my hives. This worked quite well for me. However, I know of people for whom this did not work. The general rule of thumb is that if I bear has already gotten into a hive (or presumably another food source) before, it will go right through an electric fence without hesitation because the shock provided isn’t too large of a deterrent. However, if the bear has never raided a hive before, the electric fences will often work. I would imagine that well-fed bears in a zoo are less likely than wild bears to want to go through an electric fence.