The first aim of my project is to isolate different strains from the dregs of commercial bottles. Before doing this however, I want to mention my sources for growth conditions and culture media for different strains of Brettanomyces, Saccharomyces, Lactobacillus, and Pediococcus. The best online source so far for Brettanomyces research is the Brettanomyces Project by Chad Yakobson, MSc. For his dissertation, he grew different strains of Brett under various conditions and characterized flavor compounds produced from fermentation on a molecular level. I wanted to make sure I cited his work as he is the authoritative person online for Brett and I will rely heavily on his techniques. Jamil Zainasheff’s Yeast book also has great information.
My goals are not as extensive as Chad’s dissertation. I just want to make homebrew with the strains grown in my lab and learn what I can. To this end I need good sources of wild yeast and I obtained the dregs from two American sour ales, Russian River’s Santification and Temptation. I was lucky enough to be at a tasting of NYC’s Brew York crew who were generous to leave the dregs for research purposes. You can see pics of me isolating yeast and the eventual inebriation here. That was a crazy night with an insane amount of bottles being opened and sampled. Huge thanks to Jonathan Moxey for organizing the event and Kenny Sherr for bringing Temptation. Lee Williams of Hoptopia provided the Sanctification. It was great to meet so many awesome beer geeks in one room! I brought sterile pipettes and centrifuge tubes from the lab and collected the dregs as quickly as I could.
I brought the yeast back to the lab and followed this protocol harvest them. All lab procedures were done under sterile conditions:
- Equilibrated at 4°C for two days.
- Transferred to a new centrifuge tube and centrifuged at 4000 rpm for 5 minutes.
- Separated liquid from pellet in tubes.
- Took 20 μl samples to visualize under a microscope.
- Added 2 mls of sterile wort to pellets along with 2 mls of 100% glycerol.
- Added 2-3 mls of 100% glycerol to supernatants (beer siting on the pellets).
- Aliquoted into 0.5 ml samples and froze at -80°C.
Awesome.
As you mentioned in the last bit. I am really interested in the microscope pictures. I think it would be great to have an online reference to pictures of these organisms.
You mentioned earlier that you would like to get some pure cultures. I think the best option is to contact the Brewing Science Institute. They seem to have tons of these strains. Also contacting Chad Y, he seems to be very helpful to homebrewers. I read that one of his first batches at Crooked Stave will have 10 varieties of Brett. Wow.
Yeah our microscope can go to 100x but unfortunately the computer attached to the scope is giving me problems. I’m going have to tweak the settings to get good pictures.
Thanks for the suggestions on the yeast, I’m definitely going to contact Chad first. I need good controls to compare different strains.
Hey Jason,
Exciting stuff! On the new(ish) Brettanomyces Project site I have photos up of 7 commercially available strains of Brettanomyces on 3-4 different medias showing colony morphologies. Giant colony morphology is certainly the way to tell strains apart. Under the scope a pure culture will have multiple forms making it look like a mixed culture when it’s not. Also all the research is up there now in one form or another.
Better then using the strains from the yeast companies is to collect your own! Shoot me an email and we can talk more about sources for unique Bretts. I have 10 strains banked now so I could send you some stuff as well. But I’d encourage you to collect some new strains!
Chad
Chad,
Thanks for posting a comment! Funny, I was going to shoot you an email this weekend and ask you the questions you posted…
I’ll send you an email with more concise questions on isolating different strains from commercial dregs. Good to know to look for giant colony morphology. Right now I have some plates growing at 30C with Bromocresol, and will compare uptake of the dye or lack of. I’ll let them grow out more to see if I get different morphologies.
What I critically need however is controls. I was thinking of ordering from Wyeast the different strains but I was going to contact you if you have some. All I need is very little. If you have dry-ice I can pay for shipping.
Again thanks for posting, and great work on your dissertation. I particularly like the analysis of different compounds produced. We do have mass specs here at Columbia but unfortunately that sort of research would be frowned upon. Shame really!!
Best,
J