By Valerie Smith
For the Oregon Beer Growler
You know from instinct how certain music and sounds make you feel — relaxed, happy and energetic. It might even evoke vivid memories. Music is diverse and exists in every culture around the world. Humans like music. Plants even respond positively to exposure to music. Studies have shown that high-frequency sounds produce more antioxidative enzymes in plants. Would it surprise you that not only do you and your plants “like” music, but beer yeast cells do too? Sounds far-fetched, but it isn’t.
Metabolomics is the study of small molecules in the cells of an organism. In 2011, metabolomics researchers from the University of Auckland (U of A) in New Zealand did a study involving music and yeast cell growth. They used the single-celled organism Saccharomyces cerevisiae (S. cerevisiae), the species of yeast used since ancient times by brewers, winemakers and bakers. These forward-thinking lab geeks tested how S. cerevisiae reacts to sound pressure waves by putting the yeast in shake flasks along with a food source -- a glucose broth with vitamins — and let it sit overnight. They then piped in high- and low-frequency sonic vibration to the rooms where the flasks were being kept. The control for the study was a silent room. The study showed that the brewer’s friend, S. cerevisiae, grew 12 percent faster with music playing. High frequency produced slightly better results than low frequency, so it seems that any music therapy for yeast will prove successful!
Michael Kora, brewmaster and owner of the soon-to-open Montavilla Brew Works, appreciates the U of A’s findings. Kora received a bachelor’s degree in jazz studies from Wayne State University in Detroit, Mich. He played and taught drums and guitar years before delving into Portland’s brewing community. Because of his background, Kora believes music’s effect on yeast makes sense. “I think since yeast are living things, they may have some sentience, maybe on some form of preliminary consciousness. At any rate, I think that music on a very fundamental level is full of vibrations, wavelength and frequency patterns. All these measurements seem to correlate on some level with the rhythm of nature and definitely the fermentation of beer and yeast-powered products.”
Kora begins with the yeast selection when building recipes for Montavilla Brew Works. According to Kora, “Yeast is the unsung hero -- they do so much work! You treat (them) like a living thing and they’ll react like that. It’s almost like they’re human in a way. If you’re good to them, keep them healthy and happy, they’ll give back to you.” He nurtures beer development with seasonal music tracks: reggae, funk and the Grateful Dead in the summer, classical and blues in the winter and everything in between at other times. Jimi Hendrix and rock play during the cleanup.
The expansive and beneficial relationship between music and yeast may have come about because of brewer intuition, superstition or other cultural influences during the millennia. Today, the U of A’s metabolomics study proves serenading developing yeast has more benefits than anyone previously recognized. So play whatever rocks your brewhouse and the yeast will love you back.
By Chris Jennings
In the brewing process, one of the most important ingredients that is often overlooked is the yeast. We always use yeast to create our tasty brews, so why not know more about what yeast has to offer? With the variety of yeast as expansive as beer styles, there are hundreds of different combinations just waiting to be tried.
Yeast is an organism related to mushrooms that, for the purposes of brewing, consumes sugars and, as a byproduct, creates carbon dioxide, alcohol, and flavor/aroma esters. The two largest groups are lager and ale yeasts. Lager yeast is bottom-fermenting and generally ferments at cooler temperatures. Ale yeast is top-fermenting and generally used at warmer temperatures.
Lager is a German term that actually means “cold storage,” so any beer can be lagered–but not all beers are lagers. Inside the larger yeast subset, there are varieties from all over Europe that would be used in Czech-style pilsners and German Schwarzbiers. There are also American varieties that are used in “steam” or warm lager beers and the now-popular India Pale Lager. Ale yeasts have a larger variety of subcategories; including English, West Coast American, East Coast American, Belgian and German. Of course, as with all aspects of homebrewing, these generalizations do not apply to every yeast and rules are supposed to be broken.
Deciding what yeast to use for a particular beer style is usually as simple as following a recipe. Unfortunately, it can be a bit boring if you use the same American ale yeast on everything you brew. Instead of going crazy and throwing a Bohemian Pilsner yeast into your IPA, a safer first experiment would be to use a British ale yeast instead of the American; thus allowing you to see the subtle differences between the two ales.
Another option is to read up on a bunch of different yeast strains. The yeast companies do a very good job of describing the different flavor profiles of the yeast in their inventory. You can find all of this information on the Internet or at your local homebrew shops. Reading what flavors a yeast can produce will help in the selection process, but you will never know if it works until you try.
The magic of fermentation creates the majority of the flavors and all of the alcohol in the beer styles we know and love. We as brewers only attempt to create an environment for the yeast that is healthy and ensures that they will be happy. With the beer industry trying new things and creating different styles, remember: As homebrewers, we have the ability to do more experimentation. Continuing to push the envelope can be risky and not every brew is going to be the greatest, but once the experiment comes out great, that is worth all of the effort.
Stories from the print edition of the Oregon Beer Growler.