Not sure this will work but for our birdseed we've had good luck with that super hot pepper oil. Less than a teaspoon of it in a (1/2 gallon?) sized container of birdseed, shaken for 30s-1m to get it distributed has kept the squirrels and raccoons off of it. Couple times and they don't even bother.

Doesn't bother the birds, but mammal tongues light right up.