Taylor-MadeAK - Brewing Sake

The next step in the natural evolution of any alcoholic beverage, if left to its own devices, is vinegar. I happen to be a big fan of malt vinegar, but every time I've tried to grow a mother from scratch I've had no success. Personally, I believe the hops interfere, but I've also been told that hops have no effect on acetobacter. Either way, I haven't attempted it in probably 6 years or so, but today I decided to give it another try.

Problem: no unhopped beer handy. I'm also too darn cheap to go out and spend $12+ on a vinegar mother, though I may pick up some unpasteurized cider vinegar later tonight.

Solution: use some sake to make rice vinegar!

Hardware: one wide-mouth nonreactive vessel, enough cheesecloth to completely cover the mouth of said vessel, and a means of securing the cheesecloth to it so that nothing can get under its edge.

Sacrificed to the cause (aka Software): the remains of 3 bottles of homebrewed sake, which haven't been drunk because I bottled them too early and they have a little bit of loose sediment in the bottom. Total amount came to exactly 24 fluid ounces.

I put this jar in my open kitchen window for a few hours on a breezy day in hopes that I could encourage some acetobacter into colonizing it, then moved it to the relatively warm and dark space on top of my kitchen pots & pans rack. There it will stay undisturbed except for periodic yearning looks from the household brewer (that would be me). This post will be updated as the experiment progresses.

UPDATE

Here we are nearly two months from the start of the experiment, and I'm here to report success! Here is the rice wine vinegar, which has been refrigerated for a few days to put the mother to sleep:

Yes, that's the same jar of sake I covered with cheesecloth and put in my open kitchen window for a couple hours. Looks darker, doesn't it? This is what oxidized sake looks like. This would be something for you new sake homebrewers out there to observe and remember.

Moving on: On the bottom of the jar you can see the layer of grainy vinegar mother (click the image to get a better look). In a couple days I'll pour off most of the vinegar and add a couple bottles of mild ale on top of the mother to make some home-made malt vinegar. I don't have an acid-base indicator to use in titrating the acetic acid percentage of the vinegar just yet, but I'll pick up a small head of red cabbage next time I hit the grocery store to make some. It's definitely acidic, though: a scant teaspoon will fully neutralize 1/8 teaspoon of baking soda.

More importantly: in spite of being thoroughly oxidized and soured sake, it tastes pretty darn good! I'll probably use the entire batch the next time I make sauerbraten....

UPDATE 2

I titrated the vinegar today. I tried to take pics of the process, but they all came out really blurry so I won't torture you with them. The end result is that the home-made rice vinegar is about 3.75% acetic acid. The really low number is due to the acid evaporating off during the really long fermentation time. Oh well, it still tastes good!