Hmmm...I do keep olive oil around but haven't used it much for a while. I've never OP'd with it. I mostly use coconut oil for OP and cooking, or sunflower oil which I keep in the fridge. I know coconut oil is very stable, and the refrigeration ought to take care of the sunflower oil. In general, do you think rancidity is common with most olive oil? Do you avoid it yourself?