I'm afraid not. The "glass" is not actually glass but polycarbonate (plastic). There are certain juices, that are known as Tank Crackers, that you need to avoid. Cinnamon flavors are among them, which is why it is mentioned in the warning. Also be wary of citrus, pineapple and banana flavors. There is a list on this forum, that will help you figure out what to watch out for. Just search for tank crackers.