It's not coffee! I am not a coffee drinker... I just drink out of coffee cups.
If you ever have kombucha that over-fermented and turned into vinegar, a good fix is to put some apple cider in it. Takes away some of the bite.
Rabbit trail: This is MY coffee cup. It is currently the only coffee cup that I own and is not being used to hold pencils. It hangs under the kitchen cabinet with four other white coffee cups belonging to other family members. What makes my cup the odd one out is that it has my friend's wedding date and both their names on it. That is really hilarious if you think about it long enough. Every morning I get up, eat breakfast, and subconsciously remind myself of my friends' wedding anniversary. It's like part of my daily routine. I can see why many companies use coffee cups as advertising tools.