Tag Archives: Brettanomyces

ITS-PCR of WLP644 Brettanomyces bruxellensis trois

A couple of days ago, Omega Yeast Labs posted an update on their facebook page, where they stated that they’ve done 5.5S rDNA sequencing on White Labs’ WLP644 Brettanomyces bruxellensis trois strain, and results showed that it was actually a strain of Saccharomyces cerevisiae. Since I have some pure cultures of the yeast strain myself, and am currently doing lots of ITS-PCR for work-related things, I decided to test WLP644 myself. Note, I haven’t done any sequencing, just amplification of rDNA (ITS1, 5.8S and ITS2) using the primers ITS1 (5′-TCCGTAGGTGAACCTGCGG-3′) and ITS4 (5′-TCCTCCGCTTATTGATATGC-3′), and then digestion of amplicons using the HaeIII restriction enzyme. The amplicon size of Saccharomyces yeasts is 840-880 bp, while the amplicon size of Brettanomyces yeasts is around 500 bp. Digestion of the amplicon with HaeIII results in a four-band pattern for Saccharomyces cerevisiae (320, 225, 180, 140 bp), and a two-band pattern for Brettanomyces bruxellensis (380, 100 bp). Anyways here is my gel:


First lane 100 bp ladder, second lane WLP644 amplicon, third lane HaeIII-digested WLP644 amplicon, fourth lane S. cerevisiae A62 amplicon, fifth lane HaeIII-digested S. cerevisiae A62 amplicon, sixth lane negative control, seventh lane 100 bp ladder. I unfortunately didn’t include any positive control for Brettanomyces (500 bp amplicon; 380 and 100 bp HaeIII-digested fragments), as I didn’t have any easily and rapidly accessible, but the results should still speak for themselves. It seems very likely that WLP644 is in fact a strain of Saccharomyces (cerevisiae) and not a Brettanomyces yeast (or at least contains Saccharomyces yeast in case WLP644 is a blend, and the single colony I’ve purified and extracted DNA from was Saccharomyces). This is basically a confirmation of Omega Yeast Labs’ results.

Edit: For more (great) information, check out these posts on Sui Generis and Embrace the Funk!

Pham T, Wimalasena T, Box W, Koivuranta K, Storgårds E, Smart K & Gibson B (2011) Evaluation of ITS PCR and RFLP for differentiation and identification of brewing yeast and brewery ‘wild’ yeast contaminants. J Inst Brew 117: 556-568. Full-text available here.

Homebrew: Bottling Bret, you’ve got it going on – 100% Brett B IPA

Today I bottled the Brett IPA I brewed up three weeks ago. I managed to squeeze 29 bottles (0.33L) out of the 10 liter batch, so am quite happy. Gravity had fallen to 1.012, meaning an apparent attenuation of 80%. This is in the range of the Brett B strain mixture I used (WLP644), though some have reported apparent attenuations up to 85-90%. Hopefully I won’t get any bottle bombs. 1.012 seems perfect for a IPA in this strength. I had a small taste sample, and the reports of tropical and pineappley fruitiness of this strain are true, as it felt like I was drinking juice. This will be very interesting to drink in a couple of weeks!

Homebrew: Bret, you’ve got it going on – 100% Brett B IPA

Another brewday behind, and today it was time to brew a small batch of an American IPA hopped with Nelson Sauvin and Galaxy, and fermented with Brettanomyces bruxellensis Trois (WLP 644). The brewday was very smooth, and am already very eager to taste the results, as the wort was tasting fantastic, and even the yeast starter was drinkable. Hoping to get a fruit bomb, as many have reported that using this strain as the primary fermenter results in pineapple and passion fruit aromas, while the hops should lend their share as well. Hit a gravity of 1.064 (16.2 brix), so guessing this will end up at 6-7% ABV depending on how dry this ferments. I tried using a quite high mash temperature (68° C) and some oats in the mash, as the yeast strain is quite attenuative and it produces no glycerol, which results in a thinner body and mouthfeel. It will be really interesting to taste the results! Recipe below:


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Homebrew: Plans for a 100% Brett B IPA

Bret you've got it going on

After reading some threads across the web on White Lab’s new WLP644 Brettanomyces bruxellensis Trois strain, I really want to try brewing a fruity IPA with it. White Labs describe the strain in the following way:

WLP644 Brettanomyces bruxellensis Trois
This Belgian strain, used traditionally for 100% Brettanomyces fermentations, produces a slightly tart beer with delicate characteristics of mango and pineapple. Can also be used to produce effervescence when bottle-conditioning.
Optimal Temp: 70-85F
Flocculation: Low
Attenuation: 85%+
Alcohol Tolerance: Medium-High

Reports on the web say that when used as the primary fermentation strain, the yeast gives off lots of tropical fruit aroma, drawing to tones of mango, guava, pineapple, and orange. This would probably compliment well with some fruity hops, such as Citra and Nelson Sauvin. There are commercially brewed Brett IPAs available (e.g. Ithaca Super Friends IPA and Anchorage Galaxy White IPA), but it would unfortunately be impossible for me to get my hands on one here in Finland. I have never brewed with Brettanomyces before, and have only tasted a couple of commercial Brett beers, so this will probably be an interesting and exciting experiment. I plan on brewing a 10 liter IPA batch and a 5 liter Brett Blonde batch (to get a better impression of what the yeast brings to beers) from the same mash, and splitting a 1.5 liter starter of the WLP644 between them. The grain bill will consist of 10% munich for some maltiness and 10% flaked oats for improved body, and I will be mashing quite high to prevent the beers from fermenting too dry. I haven’t planned the Blonde recipe yet, but the IPA recipe is presented below. I will be naming the beers after Bret McKenzie from Flight of the Conchords (because of the Brett yeast and the New Zealand hop), and the IPA will probably be called ‘Bret you’ve got it going on’.

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