Hello, I made a hair cream that I stored in a round plastic jar at room temperature and a week after making the cream, it swelled up in the jar, and when I opened the jar, it exploded and cream sprayed everywhere. I don’t understand how that happened, and how to not do it again. I was trying to look up the reason online but not sure if I even know where to start. I think it might have something to do with “hydrogen swelling” but not sure because this is the first time it has happened. I do have acidic ingredients in my cream. Was that the reason for the exploding cream? The ingredients do start off warm during the formulating process and then they eventually cool in the freezer. Was that the reason? Thank you for any help you can give to this self-taught chemist!