Member exclusive Q&As: Do surfactants have a shelf life? Can we mix powdered extracts with oil? Do you have micellar water formulas?

In the January Q&A, Karen asked: I have a question regarding surfactants. Do they have a shelf life? I have tried the internet for information, but needless to say I have not gotten any definitive answers.  They do have a shelf life, something I confirmed recently in the ickiest way possible when I found a bottle…