I wanted to give a quick update about Levulia alcomeno (a.k.a. Fermo Brew Acid). A yeast I spoke about in my previous article “Brewing Beer with Wine Yeast”.
AEB have renamed Levulia Alcomeno to Fermo Brew Acid. It’s now available for commercial brewing.
To begin with I should note that Fermo Brew has already been used by several brewers in China. For lager and IPA production with great results. I was discussing this yeast with Federico Tondini.
Federico is the AEB US Scientific Coordinator and was extremely forthcoming with information about Fermo Brew.
Furthermore; he asked me to include his email address. Its for those who want to connect with him.
Because Federico, would like to hear from people interested in Fermo Brew so, he can provide more helpful information. So, here is his email address:
The Information Provided by Federico (Scientific Coordinator AEB USA)
You can carry out sequential inoculation with Fermo Brew Acid. Federico suggests 100g/HL, for the pitch rate. So, a 500g brick is good for 5HL.
You then follow this pitch with you desired beer yeast (S. cerevisiae). So, that the fermentation can reach you’re desired final gravity.
With many dried yeasts; brewers know they can lower pitching rates below recommended suggested usage.
However; with Fermo Brew, high pitch rates and no oxygenation are recommended. Because this diverts the production towards lactic acid (instead of biomass).
You can expect pH to drop to 3.6 in 2-3 days. (depending on temperature) with Fermo Brew. Then, after the S. cerevisiae inoculation to 3.5ish.
However, there are other factors to consider which influence final pH. They are the initial glucose concentration and buffer capacity of the wort.
Furthermore please note the temperature of fermentation can result in different aromas being produced. At lower temperatures (around 18°C) you get clean, citrus and grapefruit notes.
At higher temperatures (up to 28°C) you get more tropical expressions on the nose.
Fermo Brew Acid Conclusions
To sum up Fermo Brew Acid is a natural yeast strain (L. termotholerans), which, produces lactic acid whilst starting alcoholic fermentation.
Fermo Brew Acid provides an easy and repeatable method to brew most sour beer styles. The production of lactic acid is the key constituent in most sour beers.
It’s lactic acid that gives most sour beers their distinctive taste.
Using of Fermo Brew Acid yeast provides a viable (or some would say preferred) way to produce most sour beer styles. As well as being compatible with most conventional yeasts.
What’s more, here are some documents provided Federico that are invaluable:
AEB Levulia Alcomeno – Sour Beer Yeast – An introduction on how to make the prefect sour beer with Fermo Acid Brew.
Technical Report – Sour Experiments with AEB Levulia Alcomeno Yeast – making a Brut IPA with sequential inoculation of Danstar Nottingham Yeast.
And last but not least…Souring with Fermo Acid – Its a pdf created from a webinar from AEB.
Please note: I know the pictures included aren’t great. However, if you access the three documents. Then you will have much more detailed and information and data available to you.