I freeze all my starch food products for about two weeks then put in the pantry. The freezing kills all bugs that have not hatched. Since I started doing this I bought a small chest freezer just for this purpose. I leave all my baking ingredients in the freezer and take out the rice, pasta, pet food, after two weeks. Living in the south, an infestation will happen very fast if I don't stay on top of it. It took me about two months to get rid of my first encounter with the weevils. Never again do I want that hassle to go through.