Following my original article Drinking Vinegars, I went and made my own "shrub" using frozen organic cherries and a bottle of Bragg organic unfiltered apple cider. As instructed by Toby Cecchini in his NY Times article, I added the cherries to the Bragg vinegar, covered with paper towel, secured it with a rubber band, and waited... 8 days in this case.
With the cherries, I smashed them up really good INSIDE the bag before I opened it. The freezing process should have burst all or most of the cell walls already by the formation of ice crystals, but smashing is fun, and likely expedited the fermentation process even more.
I found other brands besides Bragg at my local health food store, but this is made in Santa Barbara so it must be good, right?
The bacteria responsible for making vinegar, called acetobacters, require oxygen to function. A paper towel held in place with a rubber band should suffice for keeping other, stray bacteria and yeast from entering - while still allowing the acetobacters to boogie. This vessel stayed at room temperature for 8 days in the kitchen. My wife complained of the pungent vinegar smell but I liked it!
When the 8 days were up, I strained it through a sieve and boiled it briefly to halt the fermentation where it remained. I placed it in a glass container, covered it, and put it in the fridge. According to Toby's article, it can remain there for up to 3 months.
The end result is a pungent, piquant, puckering, punch that REALLY quenches your thirst. Besides the tartness of the vinegar, there remained a good amount of cherry flavor which I thought would be gone after fermenting but it wasn't. Full strength was way too pungent, I found myself diluting it with water 2:1 or 3:1 and sometimes adding some simple syrup out of my handy squirt bottle that sits on the counter. The more simple syrup I added, the more of the fruit returned to the palate.
By putting it in a highball or similar glass, it really is like making a non-alcoholic cocktail. What is most interesting to me is how I began to crave a glass of this after work. I would come home and immediately go to the fridge and make myself one. I even began to feel a little flu coming on and I still craved the Drinking Vinegar, unlike booze.
After all is said and done, these are really fun to make, super easy, and I'm going to start experimenting with different fruits and flavors. I suggest you do too.