I've frozen juices in mason jars before and it was fine, but what about freezing soup in a much larger container? I have these round glass (thick) containers that are about 6" diameter and 3" high. I made a crock pot stew and realized it's quite liquidy can I still freeze in these containers or will it break the glass? I will leave top room for expansion, will it naturally expand upwards because it's the point of least resistance?