Style tolerance

I’ve seen a lot of posts concerning FG for a given yeast. This is my perspective on tolerances overall for the hobby.

Each style has a starting and finishing gravity, bitterness, color, alcohol by volume, carbonation level, etc. tolerance or range. Some are very narrow and others broad.

Variability exists within our brewing systems, the weather from brewday to brewday, the water source, and on and on.

Given that we are hobbyists, we use agricultural products with variability from field to field and season to season, and most don’t have access to sophisticated laboratory facilities, we have to estimate the finishing parameters of our product.

We use various calculators, spreadsheets, and software programs based on models and formulas to help estimate the math quickly so we end up with a predictable result.

Generally speaking, if a homebrewer aims for the middle of the style guidelines, using a reasonable approach to recipe design, they will land in acceptable ranges for the various parameters and make a good to very good beer that meets the style guidelines.

However, all these variables can stack up so if a brewer has elected to brew on the high or low end of any of the allowable parameters for the style, it could result in an unbalanced, unpredictable result if any one or more of these variables are incorrectly estimated or executed.

My recommendation to the brewer who is concerned with the exact finished gravity of their product; considering all the things that are estimated, modeled, predicted, and hoped for, as long as the end result is within the guideline parameters for the style you’re good.

Sure, we want this to be exactly as we predicted but truth of the matter is when dealing with Mother Nature, human error, and all the variables involved, we’re pretty fortunate if we land within the guidelines.

What I do: aim between 50-66% of the style guidelines for original gravity, bitterness, color, and ABV based on carefully established equipment setup in my software of choice. That way, if I boil a bit too long, or don’t get 100% extract from my grain, or I was a little over/under on water volume, my hop AA wasn’t as predicted, the particular grain I got was a little darker than advertised, I misread the hydrometer, etc, etc… I’m still OK. I can be off +/- 5% or more in some cases and still be within the style guidelines.

Likewise, using the mfr’s prediction for the yeast attenuation (e.g. 71-80%), base your estimated FG on the middle of the road AA (in this case ~75%) and if it comes in higher or lower it’s not an issue.

I guess the point is use the tolerances you are given w/o expectation of perfection. Close enough is good enough.

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I mean … the Style Guides are just that: guides. Right? They’re useful because they give us a common vernacular to talk about the beers we’re brewing. “Belgian Golden Strong” is useful because it (hopefully) conjures up in each of our minds the same Platonic ideal of an ale with those particular characteristics that define a Belgian Golden Strong.

So, yeah, I agree: if one’s intent is to brew to style, aim for the center of the target so you have more room for error before your rounds miss the paper entirely. Then if you brew a recipe enough, you can start to see where your groupings are and adjust accordingly.

I agree.

As far as OG is concerned, if we take a good pre-boil gravity measurement then it is pretty hard to miss our OG. We have plenty of time and so many options to correct for desired sugars. Boil length, extract, water, sugar etc.

I find FG very dependent on wort composition and would expect lower or higher finishing gravities based on what went in the pot.

Taking good notes, knowing your boil-off, getting friendly with particular strains of yeast, brewing and brewing and brewing…it all helps us predict where we will end up. And sometimes, we still get an eye-opener. No worries, it’s just a hobby.

i worry a lot less about hitting gravities nowadays, since my “standard strength” (around 5% ABV) beers are generally accurate in terms of hitting the OG i want. stronger beers where i find i MAY or may not get better “efficiency” values especially when sugars and DME boosts are added are not so accurate.

oh but what you said re: pre-boil gravity check. my system is not good for checkign that since i would need to cool the wort down and its just an extra 15 to 20 mins i dont want to spend, since i generally hit my standard beer gravities. i havent checked pre-boil gravity since… maybe my 3rd or 4th brew, i dont even remember.

I find that the ingredients we select (and are maybe not used to) can cause the majority of surprises. Grain and yeast specifically. I have used grain types (base, crystals, munich or vienna varieties) that are new to me and I will experience something new … a beer that is sweeter or drier, darker or lighter, maybe I’m not getting the same head formation and retention, etc. Yeast strains are similar where maybe the attenuation is not what I expected, the beer is estery or has some other flavor component to it, etc. For that reason I tend to buy grains and yeast that I’m used to and I understand better. Sometimes I am making very nuanced and subtle changes to a recipe to really dial it in and only with a good understanding of my ingredients can I fine-tune things that closely. I generally brew the beer I envision on brewday but there are exceptions.

My advice would be to not use yeast attenuation rating as an absolute predictor of FG. It’s meant for comparing one yeast to another in a standardized wort. You may or may not get the attenuation from the rating. I know I’ve gotten from 65-90% with the same yeast in different worts.

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I’m with Denny on this.

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Very well said BrewBama and to the point. There are far too many uncontrollable variables to be “spot-on” with every brew.

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I do agree. My point was that in the old days I might make 5 or 6 batches and use 5 or 6 different yeast strains and I could see variables from all of those strains. By sticking to strains that I know better (and like), I should see more consistent results and be surprised less.

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