Experimental Brewing – Introduction

Authors’ Note: Way back in the Spring of 2013, we were approached to write a book titled Experimental Homebrewing that would “Out Randy” Randy Mosher and his wonderfully crazy Radical Brewing. Drew teamed up with Denny to write this book and together we quickly decided that it was a practical impossibility to achieve that goal. Instead, we pivoted to focus on the word “Experimental” and what it means. Drew was the outlandish one; Denny, the practical digger of how things worked in his brewery and for his tastes. It took us over a year and three editors to pull this book together. (Many thanks to Thom O’Hearn for dragging us across the finish line!)

Experimental Homebrewing is now approaching a decade old and is out of print, we’ve decided to bring the book online over the course of the year. Please note: you can still find used or never sold copies of the book (We’re still partial to having a physical book in hand for practical purposes!)


CLOSE YOUR EYES FOR A MOMENT and picture the classic mad scientist’s lab: bubbling beakers, electricity arcing through the air, thunder crashing on a dark and stormy night. A wild-eyed, white-frocked man is at work bringing his newest creation to life—he zips around the lab with the excitement of discovery.

Now open your eyes. Do you get this feeling when you brew? It’s okay. We aren’t sizing you up for a padded cell. We feel the same way. In fact, we’re obsessive when it comes to unlocking the secrets of beer and stumbling upon the next great discovery. New flavors! New sensations! One day, they’ll see our true genius! We’ll show them!

Ahem . . . sorry about that. It’s hard not to get carried away when you get us going about homebrewing. If you’re just beginning to brew or haven’t yet begun, oh are you in for a treat. Some of the stuff we talk about will seem bewildering, but don’t worry. There are great beginners’ books out there to help you master the basics (see page 236). In this book, we’ve tried to create a companion to those books, a book that will help you on your way from ordinary brewer to accomplished mad scientist.

For those of you who brew but go into a cold, sweaty panic when you hear the word science, don’t worry. You won’t find us breaking out anything more complicated than what was available to the average brewery of pre-Prohibition times. The idea is to try new stuff, decide if it makes beer that you like, and go from there. Really, we’re all about getting a chance to play and learn in the brewhouse.


When we first sat down and debated what this book was going to look like, we spent a lot of time talking about our brew day processes. In other words, how should we look at Denny’s techniques for brewing a world-famous bourbon vanilla porter or Drew’s constant twists and turns on a familiar style, like saison?

As we sat and pondered our successful beers, we realized the weird and wacky side of things only worked due to some reasoned experimentation. We can talk endlessly about the strange ideas we have, but the success with a recipe always comes back to the trial and error. It comes back to the experiment.

Merriam-Webster defines an experiment as “an operation or procedure carried out under controlled conditions in order to discover an unknown effect or law, to test or establish a hypothesis, or to illustrate a known law.” For scientists, an experiment is an attempt to answer a question. This is where the vaunted scientific method, oft-misunderstood cornerstone of the modern world, comes into play. The method consists of a series of steps that the experimenter must follow for it to be an official experiment:

Question: What is the question you’re seeking to answer?

Hypothesis: What do you think the answer is? You must be able to prove your hypothesis true or false.

Prediction: How will you know that your hypothesis is right or wrong?

Test: This is your experiment.

Review and analysis: Look at your results and see whether your hypothesis is true or false based on your data.

Now let’s apply the scientific method to brewing. Perhaps we want to find out if late-hop-only (hop-bursted) beers exhibit the same bitterness as traditionally hopped beers:

Question: Do late-hop-only beers exhibit the same bitterness as traditionally hopped beers?

Hypothesis: Beers with only late additions will have a noticeably less bitter flavor than beers bittered to the same calculated international bittering units (IBUs) with a start-of-boil bittering charge.

Prediction: The less bitter beer will be discernible in a taste test focused on evaluating bitterness.

Test: Brew two beers from one mash. One boil kettle will get a standard 60-minute addition with enough alpha acid units (AAUs) to create 30 IBUs. The second boil kettle will get a late-hop-only charge at 5 minutes with enough AAUs to create 30 IBUs.

Review and analysis: Does a blind triangle tasting confirm the hypothesis? How many judges got it correct? What were their comments?

This may seem pretty straightforward, but the details can sink any experiment. For instance, if we change the word flavor in the hypothesis to level, then it calls into question the prediction. What does level mean? A quantified IBU? Great! But that would require fancy equipment to measure. On the other hand, flavor allows us to use a taste test. And in the end, isn’t that what you care about?

In the professional world, scientists spend countless hours designing and redesigning their experiments to make sure that what they’re testing is what they think they’re testing. It takes weeks of careful strategizing for scientists to make sure they’ve got the right plan in place. On the other hand, the experimentation that we’ll be doing is going to be simple kitchen science—without the rigorous controls and designs that are required if you’re releasing, say, a cancer treatment. It’s somewhat scientific, but it’s not Science with a capital S. It’s about the beer.


While humans have been making beer for at least seven thousand years, science and brewing weren’t properly introduced to each other until the late 1700s, after the invention of the thermometer and saccharometer. It wasn’t until Louis Pasteur that people figured out why beer spoiled, or that yeast was responsible for wort becoming beer.

These days, a number of big breweries, such as Carlsberg and Anheuser-Busch, have large brewing laboratories focused both on quality control and on making discoveries: new strains of lager yeast, mashing profiles, maximizing efficiency, minimizing oxidation, extending shelf life, and so on. With scientists on staff at breweries, what’s left for us amateurs noodling in our kitchens, garages, and basements? Turns out there’s plenty that we need to do, for one not-so-obvious reason: our needs and concerns as homebrewers are not the same as those of the pros. We also have more freedom than the commercial brewers we know and love. Experimenting with even seven barrels of beer—a small amount by most brewery standards—will translate to a loss of $2,000 or more if the batch goes sideways. If you mess up a batch, you’re probably out $40 at the most.

Do you get different hop aromas from hops steeped at different temperatures? Can you change your flavor and aroma characters by pitching different amounts of yeast? What are the impacts of different mash tuns? What’s the best way to add vanilla or chocolate to a beer? These are all questions that we care about, but that won’t necessarily be covered by the research funds of large brewers. These questions are exciting, so we’ll do our best to answer some of them and provide jumping-off points to experiment with others.


Experimental brewing can be about individual exploration, understanding how processes work, harnessing a new ingredient, or figuring out how to save some time, but it’s also about helping other brewers by passing along what you’ve learned. One of the most fun and gratifying parts of being a homebrewer is the camaraderie with other homebrewers. Giving back and helping out by sharing the knowledge you gain through experimentation can be as rewarding as popping the cap or tapping the keg of your latest beer. Pay it forward, and your hobby will become even more fulfilling than that third pint of doppelbock.

To that end we’ve setup www.ExperimentalBrew.com, which will serve as the home for everyone’s data. That’s right, this is your chance to contribute—start performing your own experiments in Chapter 10 and join us. Share your results with the homebrewing community at large and be an IGOR (independent group of researchers)!


Drew Beechum and Denny Conn