Beer, Bread, and Whiskey History: Learning How To Cultivate Yeast At Home

photo by Maggie Kimberl

Whiskey starts with yeast, after all. Distillers explain how to start your own yeast if you can’t find any commercially.

As Covid-19 has forced most of us indoors to prevent its spread, there has been a surge of people taking up new hobbies. One of the more popular activities is baking bread from scratch, which has led to a nationwide yeast shortage. We know from distilling and brewing history that people have been capturing wild yeast for centuries, and in fact, certain beer styles, such as Lambic and farmhouse styles, are known for still being fermented with wild yeast. The wort is exposed to open air to start the fermentation process by capturing the natural yeast particles from the air. Whiskey is just distilled beer, and as with beer, bread and other things can also be fermented using wild yeast. Capturing and cultivating that yeast isn’t as meticulous as it might seem.

Sourdough starts with wild fermentation, here’s how it works:

Some descriptions of starting sourdough starter can be daunting. There’s either too much detail or not enough detail, and if you aren’t a microbiologist, you might not understand what’s going on. As long as you practice good sanitation, capturing your own wild yeast for fermentation is completely safe.

I reached out to a friend who makes sourdough pretty frequently to learn more. It turns out the basic method is, well, really basic.

“You just put equal parts filtered water and flour in an open container and set it by an open window,” says Dani Jackson. “Let it sit. Every 12 hours take half the mix out and discard it. Then add equal parts flour and filtered water. Do this for 7 days you should start seeing bubbles form in that time period. At day 7 you should have an active sourdough starter.”

You can also find all kinds of directions on the interwebs and cookbooks about capturing wild yeast from fruits and dried fruits, the latter of which is safer right now because of the threat of contamination from the virus. Basically you can take dried apricots, raisins, prunes, and more—whatever you might have around the house—and put them in a jar with water and flour to begin propagating the yeast. A yeast geneticist on Twitter created a thread about it recently, which you can read here.

It's also important to note you can use the discard portions of your sourdough starter for other recipes, of which there are plenty online. I’m totally going to be making these waffles with mine!

In addition, there’s a really great book I read about ten years ago called Wild Fermentation by Sandor Katz, which covers everything from the history of fermentation to the different methods available today.

Conor O’Driscoll at Heaven Hill, photo by Kriech Higdon

Heaven Hill Master Distiller Conor O’Driscoll offers his advice

Just a few months back, photos of the new Elijah Craig Rye alongside tiny loaves of rye bread began dotting social media. The bread was baked by Heaven Hill Master Distiller Conor O’Driscoll, whose knowledge of yeast and fermentation is one of the best in the industry.

“The knowledge we have of what yeast is and how it works is barely 200 years old,” O’Driscoll says. “Fermented foods have been around as long as humanity has been around. There’s written historical record of mead going back two centuries B.C.E., but it wasn’t until microscope lenses became halfway decent in maybe the 17th century that people could see there were these little yeasty things in the beer and the bread or whatever it was that was fermenting.”

He goes on to explain, “They knew things fermented and they knew how to make bread and beer. Basically every culture, whether it’s bread, beer, kimchi, wine, or pickles, they have figured out how to harness yeast without knowing what it was. In the 1600s lenses become good enough that they can now see the microscopic world. They identify yeast, and at that point they didn’t even figure out that it was living. They thought it was just an organic agent and they just knew that it happened to be there and it facilitated fermentation.”

Modern medicine shed light on how beer, whiskey and bread were actually made. “It wasn’t until the likes of Louis Pasteur came along that they figured out it was a living organism and that it was metabolizing the sugars from the starches or whatever the grain was and turning it into alcohol and carbon dioxide,
says O’Driscoll. “Once Pasteur discovered it was a living organism the pace of science decreased and now we can map its genome, we know every step of its biochemistry, and we know how to get in and influence its biochemistry. It can be genetically modified to do all kinds of crazy things. The reality is, though, whiskey was being made, beer was being made, and bread and everything else was being made without any of that knowledge and they were doing a halfway decent job of it.”

Distilleries keep a yeast jug

If you’ve ever been on a distillery tour, you’ve been told about the yeast jug. Historically Master Distillers have also been known as protectors of the yeast and, subsequently, would take a jug of the distillery’s yeast home at the end of the day to prevent it from being lost in case of a distillery fire or other calamity. So how are sourdough starters and the yeast jug similar?

“They are pretty much identical,” O’Driscoll says. “If you were doing what is known as the traditional jug yeast methodology, it is very similar to a sourdough starter. I have my sourdough starter at home that is ten years old now. I slow it down and I don’t feed it when I’m not getting ready to bake. I’ll usually start revving it up two weeks beforehand because it takes about that long to get really responsive.”

O’Driscoll’s feeding process

“The sourdough feeding process is you take about a spoonful and you mix it with about a cup of water and about a cup of flour and you let it sit overnight and it gets that nice beery smell. You do that every morning at the same time. From the dormant stage after about two weeks it’s at that highly active and predictable stage where you can use that to make a leaven, use your leaven to make a dough, and then you’ve got bread. That’s entirely similar to what would have been done back in the day. Regardless of whether you’re using dried yeast, live yeast, or maybe a stabilized liquid yeast, the yeast management still has echoes of that now. Basically what they would have done, every day you bring the jug yeast back and you use that to inoculate either the yeast tub or a fermenter, and you’re basically feeding the yeast in the jug and it grows up into this bigger volume and you take a jug of it home with you. It’s highly active and it ferments and then quiets down over the night, and you bring it back in the next day to make beer and from the beer you make whiskey. It’s highly analogous if not identical.”

Much of the reason distillers are so protective of their yeast is that it plays a major part in the finished product—that yeast is also very specific to its location. You can take yeast from one distillery and use it at another in a different location, and over time that yeast will change to adapt to its environment. The same is true of a sourdough starter.

“On a macro scale they will be similar, on a micro scale quite different,” O’Driscoll says. “Especially in the less controlled environs of your kitchen, you probably have other bacteria in there like lactobacillus giving it more of those sour flavors.”

Different yeasts yield different results: “The type of yeast, and there may be more than one strain of yeast growing in there—I always thought it would be interesting to see what type of yeast is growing in my starter but I haven’t got around to that yet—but the type of yeast growing in my kitchen in Louisville, Kentucky is going to be different from the yeast that growing in Washington or San Francisco or wherever, “ O’Driscoll observes. “People say, ‘Oh, I went to San Francisco and I bought some San Francisco sourdough starter, it’s the most famous sourdough starter there is.’ [But] you bring it home and you make it and that first loaf might be similar to San Francisco sourdough, but a month later it’s going to be different and a month after that it’s going to be completely different.”

Why is that? “It’s not just the yeast in your kitchen, it’s whatever flour you’re using,” explains O’Driscoll. “I use Weisenberger flour from Woodford County. I use their whole wheat blend to feed my starter, so I’m getting Woodford County yeast in mine. But again, whatever is in my kitchen is in there. When I take a scoop of yesterday’s and add a scoop to today’s flour and water the super active cultures that I’ve been feeding for the last ten years, those are the predominant strains that are growing in my kitchen.”

The enzymatic potentials of different grains are different, but you can make a sourdough starter out of just about any type of flour (yes, even cricket flour, which does exist). Even if all you have is cornmeal, you can feed your sourdough starter with that.

“It would work because there are fermentable starches in there,” O’Driscoll Says. “A lot of flour has got some malt added to it to help the conversion processes, so it would probably be a lot slower. When you make bread with it, it would taste different. There’s sourdough rye breads out there too. If you want to be a purist you would start with whole rye flour and start from scratch instead of using your wheat flour starter to make a leaven and make a rye bread out of that. If you wanted to make two starters and have two starters going, you could be a purist about it. I haven’t done that—I don’t need to feel guilty about throwing two lots of starter away.”

Alan Bishop, courtesy Spirits of French Lick

Practical yeast capturing information

As distillers rush to do what they can to address the Covid-19 pandemic, many are making hand sanitizer for first responders, hospitals, and public sale. Others are doing live streams of distillery tours to keep people learning and engaged while they are healthy at home. Alan Bishop, head distiller at Spirits of French Lick Distillery in Indiana, recently started live streaming videos with various distilling information topics. One of the topics he recently covered was how to propagate your own yeast at home. It’s an in-depth look at how to start the culture, which does involve starting with some commercial dried yeast, but he shows you how to keep that yeast going if it stops becoming available at the grocery store. He also covers how to dry that yeast out and how to keep it up to a year in the refrigerator. You can find the full video here.

Give it a try!

As we remain healthy at home to flatten the curve, it’s a great time to learn new things. Making bread is the type of skill that you can be as geeky or as basic as you want, which is great during times of great stress. If you don’t have yeast but you do have flour, you can begin a sourdough starter in minutes a day over the course of several days. If you want to get really fancy and start multiple starters and learn different types of techniques, you can do that as well.

Bread, beer, and whiskey are basics of life, and learning where they come from connects you to their history, which can be a great diversion in these trying times.