Perry, I don't rehydrate in sandwich bags. They get stretchy and hard to handle with hot water. I just open the bag, dump the contents into a 2-cup Ziplock storage container, add hot water, snap the lid on, place in cozy and let rehydrate. After dinner, I put a drop of soap in the container, add water, shake, dispose of the water responsibly and then rinse. I like the container better than a bag since it is rigid and more like eating from a bowl. And, no freezer bags with food residue to deal with.
May I walk in beauty.