Hi All, Hopefully this will be my last question before I take the plunge. I've read not to add tea's or milk to LS, but my olive oil usually comes in the house, straight into mason jars over teas and herbs. I'm thinking infused oils would be fine since the herbs were all dry when I started, and I always spritz the mason jars with rubbing alcohol to be safe. Will this require a preservative? There is no water involved.