I sometimes get confused regarding halacha when it comes to sharp foods like onions or lemons etc. So here goes:
I was dicing up some onions with a knife designated for dairy but I’m not sure whether it was used for dairy within 24 hours prior. Then while my hands were still kind of wet from the cut up onions, I touched a cover from the oil bottle. Now, is there any issue if several days later ( or maybe even the same day) I touched the cover while working with utensils used for fleishig? Or while working with a fleishig knife which I used for onions? Is there any issue with the fleishig utensils?
There is no issue at all with using the oil, or the utensils. the reason being since the amount of onion on your fingers was a minute amount, therefore even though the juice of the onion was milchig, it will still not make the bottle of oil milchig. Besides by the time you touched it again, it was already dry, and did not make the oil bottle milchig.