A Ph.D. in Beer – A Study of Beer and Fermentation Science

Off Beat Yeasts (and Bacteria)


The overall goal of this blog is to be a dumping ground for all the things I love about fermentation focusing on beer specifically but touching on all I can think of about fermentation. I am branching out slightly of late doing some sourdough, fermented vegetables, and playing with new yeast strains (Saccharomyces paradoxus to start). About a year ago, I decided that I would branch out even further than I have (or others as far as I know), into the wide world of yeasts and bacteria used in alternative fermentation.

So what does this entail? On the surface, it is making beer. I have gathered about a dozen organisms to start out and my goal is to make a 100% fermented beverage using those organisms. This may not be possible with these species since many have terrible attenutation. In the event that I cannot get a 100% fermented beverage, I will do a secondary fermentation with a saison yeast to finish out the beer. I will sample the beer before and after the Saccharomyces pitch to note what flavors are present and to have a point of reference for the final tasting. This is not a perfect system but I’m hoping to make multiple beverages with these organisms and I have to lay the ground work first. So, what are we going to start with?

Let’s talk about Yeast

Let’s start simple with a few organisms. I’m not going into a huge amount of detail in this post, just a quick introduction on a few of the species I have in house that I’m going to work with.

Yeasts: I have obtained pure cultures of a few different wine “spoilage yeasts.” The species I currently have in hand are Kluyveromyces lactis, Zygosaccharomyces bailii, Torulaspora delbrueckii, Pichia membranifaciens, Metschnikowia pulcherrima, and Hanseniaspora uvarum.

Bacteria: Zymomonas mobilis.

Feels like Latin class in here yet? You might be wondering, “Why those organisms?”

My “logic” behind this selection is pretty simple. All of those organisms are fermentative yeasts found in the phylogenetic family of Saccharomyces and Brettanomyces species, so I know they are closely related. Second, I looked up what each of those organisms were known to do and I think they might make interesting but non-toxic beverages. Basically I’m guessing I won’t get super sick drinking unpasteurized beverages made with these. I’m excited to find out if I’m wrong.

Freshman Biology Refresher

Third, there are a few blogs that mention these organisms but none that I know of that are doing primary fermentation with them, if I’m wrong please let me know. This is going to be a large task, I have a long list of organisms to get through and I want to do a few attempts at each one. I am a microbiologist and I want to bring forth the knowledge of these different organisms.

So where to begin? Good news everyone! I already did a fermentation with Kluyveromyces lactis. While this didn’t turn out exactly how I wanted the fermentation to go, I’m going to write it up and redo it for a future post. I have also started a fermentation using Zymomonas mobilis, so those will be the launching point for these posts. The Kluyveromyces lactis post will be up by the end of the week.


“The oldest and strongest emotion of mankind is fear, and the oldest and strongest kind of fear is fear of the unknown.” — H. P. Lovecraft