Wild Yeast Starter for Home Brewing

What came first beer or bread?

I don't know but I do know that you need yeast for both.

Brewing our own beer, wine, and mead is a hobby that my Love and I share. It is rewarding to craft something that helped make modern man and has a little bit of a rebel side. Many historians point to brewing as the turning point of human history. The grain fields that filled ovens with bread and tankards with grog required year-round care, transforming us from nomadic tribes to a settled society. By making our own we are being a part of brewing's long history.

Making Alcohol

Water + sugar + yeast + time = alcohol.

That's it. Yeasties get comfy in a room temperature tank of water and binge on sugar. The sugar is converted into two waste products, carbon dioxide gas and alcohol. As long is there is no competition from other types of micro-baddies the yeast will reproduce and, over the course of a week or two, consume and convert all the sugar into carbon dioxide and alcohol. You could throw table sugar and a pack of bread yeast into a gallon of water and you would have a stale bread flavored concoction with a kick. You might be able to get 4%-8% ABV (alcohol by volume) but that would be rough stuff! To make something that doesn't taste uniquely terrible you need some gear and good quality ingredients. There are many great ways to start and I'll take you through one of our brew days later but today we're focusing on the yeast.

There are several hundred commercial strains of yeast available on the market today. Each variation has slightly different qualities that produces a different end product. Some can survive in higher alcohol levels, allowing stronger brews, while others can produce a pleasant flavor or aromatic change, such as adding a nutty smell or a hint of banana. Each of these strains have been worked on for years and are proven to do a certain job a certain way every single time.

I'm going to throw all that intense specialization out the window and go catch my own like we did centuries ago.

So...how do we catch them?

Yeast is a fungus found naturally all around us. They are on dust and pollen particles floating on the breeze, make little colonies on fruit and vegetable plants, and swim in the waters around our homes. With all these yeasties around I want to be sure that I get one that is right for my needs, brewing. It needs to be able to reproduce quickly so it can crowd out other micro-baddies in my brew, be strong enough to survive in an alcoholic solution so I can get some kick out of my cup, and not make my brew taste or smell so foul I wouldn't even compost it. Seems like its a daunting task, especially when you can't even see the little buggers. Fortunately there is a way to find just the strains we need and it doesn't require much more effort that a trip to the garden.

Whether bush or vine, red or blue, little berries are the best start to a wild brewing yeast. Grapes, raspberries, blackberries, mulberries, snozberries; they all have what we want on their skins. When you think about it, it makes sense that the same thing used to make a brew would be the best source to get the yeast. I'm not going to drink a pond scum ale or a moldy stump stout but I would certainly get behind a toast with some raspberry wine or blueberry cider.  It is important to get these berries freshly picked, not from the grocer, because they will be washed as part of commercial processing and all our yeasties will be gone.

Now that I have a few different berries I can begin my starter. Here is the extensive ingredient and materials list:

Ingredients and Materials

1 cup raw honey

3 cups room temperature water*

3-4 unwashed fresh picked berries

1 glass quart jar

1 rubber band

1 sheet of fine cheesecloth big enough to be secured to the mason jar with rubber band

1 spoon or other suitable stir stick (not pictured, we used a wooden chopstick)

A note on water. Water is super important to everything, its what keeps us alive. We go so far as to add chemicals to our water sources to make it work harder for us. Unfortunately that spells doom for our yeastie buddies. If you're on city water or have a water softener that can't be bypassed use bottled spring water. If you have well water you're good to go.

I prefer raw honey because it hasn't been filtered and has more of the other particles of things like pollen and wax that give it a fuller flavor. Regular honey would work but hey, you're catching wild yeast. Give them the closest thing to nature as you can.

Wash and dry the mason jar.

Put the honey in the mason jar.

Add water until it gets up to the bottom of the jar's shoulders 

Stir vigorously until well mixed.  You want to get air in there!

Drop the berries in and stir a few more times.

Strap the cheesecloth over the mason jar and secure with the rubber band.

Pat your self on the back for being awesome.

Set this on a pantry shelf or other dark spot that won't get too warm or cold. 68-76 degrees is best but the rule of thumb is if you're uncomfortable so are the yeasties. If you don't have a suitable dark spot just try to avoid direct sunlight.

Once a day pop the lid off and give it a good couple of swirls with a spoon to get the sediments off the bottom.

With any luck in about 3-4 days you'll notice a slight pleasant bready smell after you stir the starter. That's a good sign! Even if you don't notice the smell keep working on it. Around day 7-10 it should be done. To check for doneness, give it a good swirl like you have been every day. If its done it will fizz like a soda and you'll see little bubbles popping through the starter. That's carbon dioxide!

You caught wild yeast! Dance a little and start thinking about the next phase, using and maintaining your very own personal yeast mother.

If nothing happens after 14 days you may want to try adding another 1-2 berries, preferable from different plants, and wait up to another 7 days. After that other bacteria and fungi will be attracted to the tasty honey juice and your chances of raising something awful and possibly dangerous start rising. If you notice a particularly bad smell at any point in time during the process, that could be those same bad organisms. Dump it, wash everything, and try again.

We have our own yeast mother!  Now what?

To keep your mother strong you will want to feed it weekly. Once a week stir the sediments off the bottom and remove about 1/4 of the volume, or 1 cup. Use this portion as a yeast replacement in doing a small brew (less than 2 gallons), baking bread, or prepping for a larger brewing (5+ gallons). At worst it makes good compost. Add about 1/4 cup honey back to the mother and refill to the shoulders with water.  Stir vigorously to mix and aerate.

I usually do 5 gallon batches of beer, wine, or mead. Using the starter means that I will need the whole quart to get enough yeast. To do large batches you'll need one quart of starter per 5 gallons. To get to the amount needed you can split the mother and start a new jar. Take your weekly cup of mother liquid off and add it to a new, clean quart jar. Add 1/2 cup honey and fill to the shoulders with water, mixing vigorously. Your new mother should be ready in a few days, just look for the bubbly fizz.

Some information found in this post came from Jereme Zimmerman, author of Make Mead Like a Viking: Traditional Techniques for Brewing Natural, Wild-Fermented, Honey-Based Wines and Beers.  Check out his book for some great ideas about the art of mead making and a fun bit of history.