This week I check out methods to learn a yeast information sheet for brewing yeasts and methods to higher perceive the flavors a given yeast would possibly produce.
Yeast Knowledge Sheets
Correct yeast information might be onerous to come back by. A few of the higher yeast labs publish detailed information on every pressure, typically collected by brewing a “typical” batch after which measuring particular compounds current within the completed beer. Others publish solely the fundamental information reminiscent of really helpful temperature vary, common attenuation and a brief description. A couple of yeast suppliers, like White Labs have begun publishing “Spider charts” (just like the one right here) – very similar to we see for a lot of hops and malts which supplies you a greater thought of the everyday taste profile. Nevertheless just about each main yeast lab now supplies no less than their primary yeast financial institution on-line so you’ll be able to simply lookup their merchandise and get some thought of what they’re providing.
Primary Yeast Knowledge
That is the kind of information you’ll be able to anticipate to see for the overwhelming majority of yeast suppliers:
- Identify and Product ID: Most yeasts are named for the fashion of beer they aim, for instance “California Ale Yeast” or “English Ale”, however additionally they have a ID quantity related them reminiscent of WLP002 for White labs, or 1028 for a Wyeast London Ale. This helps slim issues down as some labs present a number of strains for a single fashion reminiscent of “American Ale II” or “Whitbread II” which have totally different product numbers.
- Attenuation Vary: The vary listed is obvious attenuation, and provides you an thought of the % of sugars fermented. Most brewers yeast may have obvious attenuation within the 68-85% vary. These with low attenuation gives you the next ending gravity with extra physique, maltiness and residual carbohydrates whereas these with excessive attenuation will end cleaner and drier.
- Fermentation Temperature Vary: That is the really helpful fermentation temperature for this yeast pressure. Inside this temperature vary you’ll usually get the very best yeast efficiency and finest total taste. In case you ferment too chilly, the fermentation could also be gradual, stall or not end correctly. Fermenting too sizzling may end up in extra esters (fruity flavors) in addition to fusel alcohols. Fermenting outdoors the vary can even provide you with off flavors.
- Flocculation: A measure of how briskly the yeast “drops out” of suspension after the fermentation is full. A extremely flocculant yeast will fall out quickly, leaving your beer clear in just some days, whereas a low flocculation yeast can keep within the completed beer for a while.
- Alcohol Tolerance: A measure of the % of alcohol the yeast can tolerate earlier than it shuts down. Many beer strains usually are not as tolerant as wine yeast and might solely deal with decrease alcohol ranges within the 6-10% vary. In case you try to make a excessive gravity beer or barley wine with a low to medium alcohol tolerance yeast, you’ll find that the fermentation typically stalls leaving you with a really excessive ending gravity and improper steadiness. So if you’re working with a excessive gravity fashion, you have to choose a yeast that may tolerate larger alcohol.
- Description: These fluctuate tremendously, however the description will usually embrace one thing concerning the supply or heritage of the yeast, types it’s utilized in and one thing concerning the taste and character of the yeast pressure.
Superior Yeast Knowledge
- Diacetyl (Buttery): A buttery popcorn-like taste widespread in lots of English Ale strains. Whereas fascinating in English ales, excessive ranges of diacetyl usually are not fascinating in lots of continental and US beer types.
- Phenolics (Pentainedione): Current in lots of Belgian yeast strains, phenolics produce a clove and spicy end that’s distinctive. To some it will probably tackle a smoky taste and at very excessive ranges end in medicinal and band-aid flavors. One other good instance is Bavarian Witbier yeast which has a particular clove character from phenolics produced. Pentainedione is loosely associated to diacetyl, this compound has extra of a honey like taste that’s simply picked up within the completed beer.
- Acetaldehyde (Inexperienced Apple): A inexperienced apple tasting taste that’s truly an intermediate compound created throughout fermentation. Most yeast strains will clear it up, however some yeast strains have larger residual ranges than others leaving a slight inexperienced apple end to the beer.
- Esters (Fruity, Isoamyl Alcohol, Ethyl Acetate): Typically listed individually, however these are all esters. Ethyl acetate is the strongest of widespread esters with a fruity pear like taste and aroma. Isoamyl acetate is one other kind with a taste extra carefully aligned with bananas or “circus peanuts” and is a significant part within the banana taste we get from Bavarian Witbier yeast. In excessive, very excessive ranges of esters can provide you a solvent taste like nail polish or turpentine.
- Alcoholic (1-Propanol): These are each measures of larger degree fusel alcohols you would possibly affiliate with onerous liquor. Fusel alcohols are produced by many strains for those who ferment at a excessive temperature, although all yeast produce them to some extent.
- Ethanol (Common Alcohol): That is simply the traditional alcohol produced by the yeast. So for those who see this stat, it’s usually the alcohol degree of the pattern beer produced to gather statistics.
- Hours to 50%: The variety of hours for the yeast to ferment 50% of the fermentable sugars.
- STA1 Constructive or Damaging: This can be a pretty new stat, however many labs have began publishing it. The STA1 gene is an indicator of a selected variant of saccharomyces cerevisiae (regular brewing yeast) known as diastaticus which is widespread in wild yeast. Sadly the presence of this STA1 gene signifies that underneath sure environments the yeast can ferment residual carbohydrates {that a} regular cerevisae pressure wouldn’t ferment, and in addition can do it over an prolonged interval. This may end up in instability within the completed beer, prolonged fermentations and even bottle bombs. So some labs have began genetically testing their strains to determine STA1 optimistic yeasts.
I hope you loved this week’s article on yeast statistics. Thanks for becoming a member of me on the BeerSmith Residence Brewing Weblog. If you wish to take the guesswork out of brewing, please strive my BeerSmith recipe software program from BeerSmith.com. Make certain to enroll in my publication or my podcast (additionally on itunes and youtube) for extra nice recommendations on homebrewing.
