[quote=“deliusism1”]He said that his OG after adding the sugar was 1.080, meaning that his yeast would have to attenuate to the tune of 102% to get 9.1% ABV. What yeast on earth can do that, I ask? I’m pretty darn curious.[/quote]Not sure what formula you’re using, but standard ABV estimation is (OG-FG)0.133, so (80-10).133 = 9.3% and I bet he’ll end up below 1.010.
+1
the 0.133 number is known as the F-factor. It changes depending on your expected ABV%. In this case .133 is the correct F-factor
[quote=“deliusism1”]
He said that his OG after adding the sugar was 1.080, meaning that his yeast would have to attenuate to the tune of 102% to get 9.1% ABV. What yeast on earth can do that, I ask? I’m pretty darn curious.[/quote]
Are you sure you aren’t mistaking ABV for ABW?
The formula I’ve always used is ABV=(OG-FG)1051.25, and I have every reason to believe that this is accurate. So for an average strength beer, brewed to OG 1.050, fully fermented with a yeast that attenuates to 75%, the answer would be: 0.03751051.25= 4.92% ABV. I’ve seen other equations as well, and they come up with answers that are very close to those obtained by the formula I’ve shown. Again, though, the rate of attenuation you’re quoting is very high (87.5% by my reckoning), much higher than for any beer yeast I know of. I was mistaken in my original calculations, I’ll admit, but I’d still like to know what kind of yeast would give that level of attenuation, unless it’s something other than a beer yeast. Champagne yeast, or repeated pitchings of beer yeast, would give a level of attenuation comparable to that, but his original post said nothing about that. He made it sound like he just pitched some yeast and got that kind of attenuation with no problem. He also said his OG was “1.068 at pitching”, whatever that means, and also reasoned that his actual OG was significantly higher than that (1.080), without supplying any logical or scientific reasoning to support that conclusion, so I can’t help feeling a little skeptical- or at least confused- about the whole scenario.
[quote=“deliusism1”]
The formula I’ve always used is ABV=(OG-FG)1051.25, and I have every reason to believe that this is accurate. So for an average strength beer, brewed to OG 1.050, fully fermented with a yeast that attenuates to 75%, the answer would be: 0.03751051.25= 4.92% ABV. I’ve seen other equations as well, and they come up with answers that are very close to those obtained by the formula I’ve shown. Again, though, the rate of attenuation you’re quoting is very high (87.5% by my reckoning), much higher than for any beer yeast I know of. I was mistaken in my original calculations, I’ll admit, but I’d still like to know what kind of yeast would give that level of attenuation, unless it’s something other than a beer yeast. Champagne yeast would give a level of attenuation comparable to that, but his original post said nothing about that. He was saying that an OG-FG differential of 0.068 ( indicating an attenuation level of a more believable 77.5%) would give 9.1% ABV, which is WAY off the mark. Are you assuming that he’s using something other than beer yeast to ferment his beer, or is there something else you’re factoring in here that you’re not mentioning? I don’t know why you’re assuming that the yeast he’s using will attenuate to such a high degree. But I’ll take an open-minded look at whatever information you have to put out there. After all, I’m no scientist, and I’m certainly no professional brewmaster.[/quote]
Using your formula, with an OG of 1.080 and FG of 1.012 (FG is based on a refractometer calculation from Sean Terrill, which was dependent on the estimated OG calc as I broke my hydrometer, which is why I originally posted this), I get 8.925 but you stated in a response above that you calculated 8.1%. Beer Alchemy calls this 84% apparent attenuation. The ABV from Beer Alchemy is different though (9.1% ABV) so there are obviously different formulas floating around.
The formula for determining alcohol for specific gravity is as follows:
(OG-FG)*Ffactor
this can be confusing to some, because the OG isn’t used in the formula as read on a hydrometer. for the formula: 1.050 = 50 and 1.010 = 10
so with these numbers, the formula is (50-10)*.13 = 5.2%abv
Ffactor chart:
anticipated ABV% range = Ffactor
2.2%-3.3% = .128
3.3%-4.6% = .129
4.6%-6% = .13
6%-7.5% = .131
7.5%-9% = .132
9%-10.5% = .133
10.5%-12% = .134
12%-13.6% = .135
There are other ways to determine ABV, but this is the most accurate way.
[quote=“airlocksniffer”][quote=“deliusism1”]
The formula I’ve always used is ABV=(OG-FG)1051.25, and I have every reason to believe that this is accurate. So for an average strength beer, brewed to OG 1.050, fully fermented with a yeast that attenuates to 75%, the answer would be: 0.03751051.25= 4.92% ABV. I’ve seen other equations as well, and they come up with answers that are very close to those obtained by the formula I’ve shown. Again, though, the rate of attenuation you’re quoting is very high (87.5% by my reckoning), much higher than for any beer yeast I know of. I was mistaken in my original calculations, I’ll admit, but I’d still like to know what kind of yeast would give that level of attenuation, unless it’s something other than a beer yeast. Champagne yeast would give a level of attenuation comparable to that, but his original post said nothing about that. He was saying that an OG-FG differential of 0.068 ( indicating an attenuation level of a more believable 77.5%) would give 9.1% ABV, which is WAY off the mark. Are you assuming that he’s using something other than beer yeast to ferment his beer, or is there something else you’re factoring in here that you’re not mentioning? I don’t know why you’re assuming that the yeast he’s using will attenuate to such a high degree. But I’ll take an open-minded look at whatever information you have to put out there. After all, I’m no scientist, and I’m certainly no professional brewmaster.[/quote]
Using your formula, with an OG of 1.080 and FG of 1.012 (FG is based on a refractometer calculation from Sean Terrill, which was dependent on the estimated OG calc as I broke my hydrometer, which is why I originally posted this), I get 8.925 but you stated in a response above that you calculated 8.1%. Beer Alchemy calls this 84% apparent attenuation. The ABV from Beer Alchemy is different though (9.1% ABV) so there are obviously different formulas floating around.[/quote]
I think the most likely answer is that someone is this scenario is confusing apparent attenuation with real degree of attenuation, which is a different thing. I’ll be the first to admit that I’ve never gotten to the bottom of what exactly real degree of attenuation is, as opposed to the ABV determined by the aforementioned equations. I have a feeling this whole thread of discussion will lead me on to a new research project, one which I should have undertaken years ago.
[quote=“deliusism1”] Again, though, the rate of attenuation you’re quoting is very high (87.5% by my reckoning), much higher than for any beer yeast I know of.[/quote]There are many yeasts that attenuate higher than 87.5% including many Belgian strains, Scotch ale, and US-05. Of course, it depends on the wort composition, the health and pitch-rate of the yeast, and the fermentation. If you’re using the manufacturer’s attenuation figures to judge actual performance, be aware that the number they advertise is only to be used to compare the potential of one yeast to another in their catalog, not the actual attenuation that you’ll get in a real fermentation.
[quote=“deliusism1”]I think the most likely answer is that someone is this scenario is confusing apparent attenuation with real degree of attenuation, which is a different thing.[/quote]If you read the post you were responding to, you’ll see that the confusion is on your part (you’re using the formula incorrectly). 
+1
Also sugar is 100% fermentable so your attenuation will improve greatly with 2 lbs added in a 5 gallon batch no matter what Yeats is used. My math shows 84% attenuation.
Where in the world are you getting this information?? A Scotch ale yeast that ferments to 87.5% attenuation??? Not a chance in hell, man.
+1
Also sugar is 100% fermentable so your attenuation will improve greatly with 2 lbs added in a 5 gallon batch no matter what Yeats is used. My math shows 84% attenuation.[/quote]
Just because sugar is 100% fermentable does not mean that beer yeast will ferment 100% of it. Beer yeast has a definite cutoff limit on what it can digest, no matter how simple the sugar is. Even the driest beer around will have at least some tiny amount of unfermented sugar left in it, regardless what strain of yeast is used. If it were a simple matter of pitching sugar into wort and letting yeast produce alcohol, every macrobrewery in the world would be using much higher proportions of sugar in their wort than they do.
IME simple sugar is 100% fermentable. Many craft breweries don’t use it because all grain produces a better flavor than grain + sugar. But a lot do use sugar, especially overseas. If there’s still a percentage of fermentable sugars and yeast have said cut-off limit, than bottle conditioning would be far less predictable. If there is still fermentable sugars, the amount is negligible.
anyway. like mentioned previously: attenuation is far more dependent on wort composition than percentages listed on websites
[quote=“S.Scoggin”]IME simple sugar is 100% fermentable. and many craft breweries don’t use it because all grain produces a better flavor that grain + sugar. but a lot do use sugar, especially overseas. If there’s still a percentage of fermentable sugars and yeast have said cut-off limit, than bottle conditioning would be far less predictable.
anyway. like mentioned previously: attenuation is far more dependent on wort composition than percentages listed on websites[/quote]
I’m not following your logic at all about bottle conditioning. If the cutoff limit of a yeast weren’t known, then there would be no way to correctly predict the amount of carbonation obtained by bottle conditioning with yeast and avoid overcarbonated bottles. You seem to be saying exactly the opposite of what I think is the real truth. How would a brewery ever carbonate a beer in bottle and not have exploding bottles if they didn’t know exactly what the cutoff limit of their yeast was?? You’ve completely lost me on that one.
[quote=“deliusism1”]
I’m not following your logic at all about bottle conditioning. If the cutoff limit of a yeast weren’t known, then there would be no way to correctly predict the amount of carbonation obtained by bottle conditioning with yeast and avoid overcarbonated bottles. You seem to be saying exactly the opposite of what I think is the real truth. How would a brewery ever carbonate a beer in bottle and not have exploding bottles if they didn’t know exactly what the cutoff limit of their yeast was?? You’ve completely lost me on that one.[/quote]
I’m saying bottle condition is predictable because simple sugar is 100% fermentable. rather than unfermented yet fermentable sugars carrying over to bottle conditioning.
edited: unless you can prove simple sugar doesnt ferment 100%, or if yeast have different attenuation when it comes to simple sugar. which is something i’ve never heard of. If you have a source for that i’d be interested.
***sorry for the edits, i responded hastily
+1
Also sugar is 100% fermentable so your attenuation will improve greatly with 2 lbs added in a 5 gallon batch no matter what Yeats is used. My math shows 84% attenuation.[/quote]
Just because sugar is 100% fermentable does not mean that beer yeast will ferment 100% of it. Beer yeast has a definite cutoff limit on what it can digest, no matter how simple the sugar is. Even the driest beer around will have at least some tiny amount of unfermented sugar left in it, regardless what strain of yeast is used. If it were a simple matter of pitching sugar into wort and letting yeast produce alcohol, every macrobrewery in the world would be using much higher proportions of sugar in their wort than they do.[/quote]
\you are wrong. how can cider go below 1.000. try putting 1 pound of table sugar in a gallon of water and see what your gravity reading is. simple sugar is 100 fermentable.
Just to lighten the mood. Sucrose 100% fermentable by yeast FTW.
+1
I should have specified that earlier. when i was saying simple sugar my assumption was:
simple sugar = table sugar = sucrose
Yes me to I should have been more specific, but I think everyone understood what we were/are talking about.
[quote=“S.Scoggin”][quote=“deliusism1”]
I’m not following your logic at all about bottle conditioning. If the cutoff limit of a yeast weren’t known, then there would be no way to correctly predict the amount of carbonation obtained by bottle conditioning with yeast and avoid overcarbonated bottles. You seem to be saying exactly the opposite of what I think is the real truth. How would a brewery ever carbonate a beer in bottle and not have exploding bottles if they didn’t know exactly what the cutoff limit of their yeast was?? You’ve completely lost me on that one.[/quote]
I’m saying bottle condition is predictable because simple sugar is 100% fermentable. rather than unfermented yet fermentable sugars carrying over to bottle conditioning.
edited: unless you can prove simple sugar doesnt ferment 100%, or if yeast have different attenuation when it comes to simple sugar. which is something i’ve never heard of. If you have a source for that i’d be interested.
***sorry for the edits, i responded hastily[/quote]
You’re assuming that breweries that do bottle conditioning use simple sugar for priming, which I would have to say is a pretty unfounded assumption.
