Not sure what you mean by oxidizing
juice. When I steep certain bottles I simply put them in a draw and leave them there for a week or 2, shaking one a day or every other day. I personally never leave the caps off my bottles as air can help degrade the nicotine. Some do so for
juice that are too perfumery but if your just trying to better marry the flavors together just let it sit and shake every now and then.