My steeping is as follows, mix juice shake well, next day, take lid off, squeeze bottle to replace the air in it, recap bottle. Leave for 1 week but shake daily when I remember to do them, taste, if needed, repeat the above for another week.
Never found any juice that has changed dramatically after 2 weeks of steeping, but the flavor has got more intense if left longer.
Most if not all fruit juice is good within a day or two of mixing, tobaccos are best after 2 weeks or longer if I have time to leave them.
All juice is keep in cool dark place.