Skip to main content

Learning Yeast Secrets Will Make Beer Better

The April 20, 2015, issue of Chemical & Engineering News (C&EN) carried an interesting article about Yeast.  The publication is normally only read by scientists, but I was able to acquire a free copy and read the article.  Most, if not all, of the information in this post comes from that article, entitled Tapping Yeast's Genome by Matt Davenport.  The article features the Colorado brewmasters Keith Villa (of Blue Moon Brewing) and Max Filter (of Renegade Brewing Co.).

Davenport tells us that "Yeast are perhaps the best understood organisms on the planet." Scientists have studied yeast for years, and with DNA sequencing equipment coming down in price, they are gaining even more knowledge about it.  If you're reading this blog, you know that yeast are the main workhorse ingredient in home brewing.  Yeast consume the sugars in beer (and some of the fatty acids from hops!), and give off alcohol, carbon dioxide, and a few esters that can improve the beer's flavor.
Scientists think humans stumbled onto the fact that yeast produce alcohol by accident, perhaps eating a fruit that fell off a tree and naturally fermented, or grain that got wet and fermented in a jar.  Since then, brewers have spent their time learning what makes yeast healthy and productive.  In the process, they began selectively breeding yeast to develop strains that delivered the flavors and qualities they wanted for beer and wine.

Avery Brewing Co. produces about 30 different kinds of beer, many of which use different yeast strains, in the same equipment.  There is a concern that a yeast strain from one beer (like a Belgian wit or a German hefeweizen) might not be completely cleaned out of the fermentation tanks when a different beer (which uses a different yeast) is brewed in the same vessel. This could result in the beer having an "off" flavor (e.g., an IPA with banana and clove flavors), and might require Avery to dump the entire batch.  They'd prefer not to have this happen.

One way they're doing this is to work with the university to uniquely identify all their yeast strains.  These "fingerprints" will be used to help the brewery determine if an IPA contains yeast from another beer style (hopefully before the contamination ruins the batch).

Something else scientists are doing is using biochemical tricks to block each gene in the yeast in order to figure out its function in the organism.  This will eventually enable them to begin producing "designer yeasts".  They've already managed one modified yeast that produces significant amounts of a banana flavored ester.  The brewer who tried using a batch of it said that it created a beer that tasted like a banana milkshake.  However, given that many people are averse to eating genetically modified food products, they don't plan to make the yeast available for use at this time.  It's being cryogenically stored for the future.


Popular posts from this blog

Things I've Learned Brewing with The Grainfather, Part 2

In the last post, I shared an overview of The Grainfather, recommended equipment to use with it, and an overview of the brewing process.  In this installment, I'm going to talk specifically about mashing and sparging. Having brewed over a dozen batches with it, I'm finally becoming very comfortable with the device, the mash process, and how to get what I want out of it. I don't consider myself a "master" of it yet, though.

For those who have never done all-grain brewing, I want to provide a quick overview of the mash process itself.

Mashing - With or Without The Grainfather
The goal of mashing is to turn the starches in the grain into sugars. More specifically, you want to turn the starches into a mix of fermentable and unfermentable sugars that provide the flavor profile associated with the beer you are brewing. A sweeter beer might warrant more unfermentable sugars. A more dry beer will demand few unfermentable sugars.

To a great extent, controlling the amount o…

Brewing with The Grainfather, Part 3 - Cleaning and Overall Thoughts

In Part 1 of this series, I introduced The Grainfather and discussed how to use it for mashing and sparging.  In Part 2, we talked about boiling and chilling the wort with The Grainfather and its included counterflow chiller.  In this final segment, we'll discuss cleanup and overall thoughts about the device and its usage.


Once you've pumped the wort from The Grainfather into your fermenter and pitched your yeast, you're well on your way to a delicious batch of homebrew.  Unfortunately, you've still got some cleanup work to do.

The cleanup process in my experience will take 20-30 minutes.  It involves the following tasks:

Removing and discarding the grain from The Grainfather's grain basketCleaning the grain basket, kettle, recirculation tube, and wort chillerCleaning all the other implements used in brewing (scale, scoops, mash paddle, etc.) At the end of the brewing process, there will be hops bags (if you used them), grain and other residue, and usually so…

Brewing with The Grainfather, Part 1 - Mashing and Sparging

(Important note:  This article series is based on the US version of the product.  Prices are expressed in US dollars, measurements of temperature and volume are in US units unless otherwise noted.)

iMake's The Grainfather is an all-in-one RIMS brewing system designed to be used indoors with household electric current.  It includes the kettle, grain basket, recirculation tube, pump, electronic temperature controller, instruction book, and counterflow chiller.  It does not include a mash paddle, fermenter, cleaning supplies, or pretty much anything else.  The price is around $800-900 depending on where you shop and the discounts offered.

The Grainfather handles mashing, boiling, recirculating, sparging (to a degree), and chilling of the wort.  You'll still need a fermentation vessel of some sort and some other supplies we'll discuss later.

Grainfather Assembly and Initial Cleaning

Assembly of The Grainfather in my experience was pretty easy overall.  There were a couple of s…