As you may know honey is naturally preservative, ie it won't ever spoil on its own. Honey has some natural anti-bacterial properties in it, bees are pretty awesome that way. Of course one of the main reasons that honey won't go bad is because sugar is a preservative. Yes, sugar. Ever noticed how the bag of sugar in your pantry also never goes bad? Sugar at very high concentrations is a preservative. Think of the fruit preserves your grandma used to make perhaps.
Anyway just because honey is a preservative doesn't mean there's not some of our friendly yeasty pals sleeping dormant in the honey just waiting for it to become diluted enough to get to work on all that glorious sugar. The key to harvesting yeast from honey is to get raw or unpasteurized honey. I was lucky enough to buy a whole bunch from a neighbor of mine that keeps hives in their back yard. So the yeast is a uber-local, yay!
Anyway, what you do is get a sanitized container, like an ehrlenmeyer flask or heck use a clear beer bottle. Add some of the unpasteurized honey, add about 4-5 times as much water as honey, plus a bit of yeast nutrient or energizer. Swirl it all up to dissolve the honey and nutrient in the water and then stick a bung and airlock on and wait. Don't become discouraged it may take a few days, my concoction sat around doing what looked like nothing for a couple of days before I noticed the beginnings of fermentation.
I've only done this once and it worked, and was not contaminated so I'm not sure if that's typical with harvesting yeast from raw honey or if I'm just lucky. However you will likely be able to tell by sight and smell if you have an infection. if it looks like you've just got yeast let it ferment completely and let the yeast settle. Then draw off some of the fermented liquid (which is technically mead) with a thief or baster and give it a taste. Mine had some fruity notes which I'm not sure if they were from the honey or the yeast (the local honey had a really fruity flavor to it) and no off tastes like bandaid or solvents.
If the yeast seems good then on to the next step: ferment a beer with it! which I'll be doing hopefully this weekend. I put together a simple recipe for a sort of belgian pale ale and I'll be adding my small starter of wild yeast to it and see what I get.
Thus was born Rhubarb Menace.
With the success of my Dark Cherry Whatever I decided I would brew another beer and ferment it using the leftover pressed fruit from a wine. This time I used the crushed and dessicated grapes from my small grape harvest this year. I had enough grapes this year to make about a gallon of wine, I pressed the grapes and then added the pomace into a batch of Merlot that I made from canned concentrate, then I pressed them again and put them in the freezer until i was ready to make this beer.
I dubbed this beer a "whatever" since It's not really any particular style, maybe Belgian Dark would be the closest, but it doesn't use a Belgian yeast. I'm not even sure it's an ale since it fermented with wine yeast (though it did ferment at ale temperatures).
So after my somewhat successful attempt at a gruit I decided to make a real recipe using grains of my own choosing and quantities of herbs from the yard. I decided I wanted to use the Sweet Cicely and Monarda that are growing in the yard. We had also been harvesting a lot of Rasberries at the time so I decided to use some raspberry leaves in the brew as well.
I mentioned before that I'm going to label beers fermented with my wild yeast under the name Feral. Well as a sort of sub-Feral line I'm going to label beers hopped/spiced/flavored with items from my yard under the name Backyard. These are currently all very experimental beers (obviously).
I'm very interested in Gruits, or beers that are brewed with herbs that aren't hops. Hops are actually a rather recent addition to beer as an ingredient. (Please note: the following history lesson is mostly hearsay.) You may have heard of the Reinheitsgebot or German/Bavarian Beer Purity law limiting the ingredients of beer to water, barley, and hops (yeast was not yet understood as an ingredient).