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ThatS197Guy

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Hey everyone,

I brewed a block party summer ale from northern brewing and I don’t think I boiled the wort hard enough but it’s been fermenting for 2 weeks and one week was colder temperatures so I got a heat pad to make it around 70F and it’s been at that for a week under a blanket for darkeness and warmth. I just opened it up and the potential ABV reads around 2% and it’s supposed to be a little above 4%. Now there any action from the looks of it with the yeast. How can I raise the ABV from this point?
 

ncbrewer

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The hydrometer has a scale that reads potential alcohol, but that's for unfermented wort, and it's based on 100% attenuation - probably for wine makers. Most home brewers just use the SG scale. ABV = (OG - FG) x 131.25

Welcome to HBT.
 

grampamark

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If you're using a hydrometer, and looking at the "potential ABV" scale, you’re doing it wrong.

Reading across from 2% on the ABV scale to the specific gravity scale would show an SG of around 1.008-1.010. If you took an original gravity reading before pitching the yeast you would subtract the current reading from the OG and multiply by 131.25 to get the current ABV. The ABV scale on the hydrometer is based on knowing how much potential fermentable sugar you have and the average attenuation of your yeast. If you study the charts which come wrapped around the typical $8 hydrometer this will start to make sense.

Take another sample and make sure you're reading from the correct scale on the hydrometer.
 

glienhard

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Exactly, just read the specific gravity off the hydrometer. Then you can manually calculate or use one of many free calculators online.

What was your OG and then what was the reading you just took?
 
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ThatS197Guy

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Exactly, just read the specific gravity off the hydrometer. Then you can manually calculate or use one of many free calculators online.

What was your OG and then what was the reading you just took?
Thanks for all the info everyone is proving
It is currently 1.014 but I did not know to take the OG reading so it is unknown
 

Qhrumphf

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Those triple scale hydrometers have a lot of noise. Brewers can use two of the three scales. The one you're looking at is potential alcohol, and is mainly for distillation, and not useful for brewing. The °Brix scale refers to percercentage sugar/sucrose, used for fruit juices/honey/sugar syrups/etc and some winemakers use °Brix, but it's functionally the same as and can be used as °Plato (percentage total extract, not just sucrose), which some brewers (mostly professional) use. The last, used by most homebrewers and some home winemakers, is specific gravity as the other posters said. It's essentially a density ratio compared to water. A wort at 1.050 will weigh 1.05 times as much as water.

You can't determine alcohol from it directly. There are mathematical equations to approximate the alcohol using both a starting and finishing measurement, but direct actual measurement requires lab equipment out of the price range of most homebrewers (and many smaller craft brewers).
 

davidabcd

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It sounds like you people who've responded know what OP was saying. I actually don't. I'm only familiar with one graduation on the hydrometer--the rest may as well not be there.
It's heartbreaking to miss that OG, though, if you're interested in that sort of thing. On the bright side, it sounds like a kit? ABV would be already known in that case.
 
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Qhrumphf

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Actually, if you have both a hydrometer AND a refractometer it's possible to approximate an OG and ABV by calculating the difference between refract and hydrometer.

However as said if this was an extract kit, as long as you followed proper procedure (added the correct fermentables and had the correct volume), you can just assume the OG was what the kit said it should be.
 

glienhard

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Thanks for all the info everyone is proving
It is currently 1.014 but I did not know to take the OG reading so it is unknown
According to NB the estimated OG is 1.042. Given this and that Muntons says that the yeast supplied in the kit has an attenuation of 70%, I'd say that your 1.014 is right on the mark. At this point, RDWHAHB
:mug:
 

RM-MN

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Thanks for all the info everyone is proving
It is currently 1.014 but I did not know to take the OG reading so it is unknown
Northern Brewer says that this extract kit will have an OG of about 1.042. If you used the right amount of water that is what you get. I often suggest that brewers using extract kits do not use the hydrometer for the OG and go with what the kit says it is as mixing the wort and top off water very often gets you wrong numbers.
 
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ThatS197Guy

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It sounds like you people who've responded know what OP was saying. I actually don't. I'm only familiar with one graduation on the hydrometer--the rest may as well not be there.
It's heartbreaking to miss that OG, though, if you're interested in that sort of thing. On the bright side, it sounds like a kit? ABV would be already known in that case.
True but thought it could be altered per I thought I didn’t have a hard enough rolling boil .. have new equipment to make that not occur again
 
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ThatS197Guy

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It sounds like you people who've responded know what OP was saying. I actually don't. I'm only familiar with one graduation on the hydrometer--the rest may as well not be there.
It's heartbreaking to miss that OG, though, if you're interested in that sort of thing. On the bright side, it sounds like a kit? ABV would be already known in that case.
Yeah it’s a northern brewing kit and I made slight changes such as adding fruits
 

davidabcd

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Actually, if you have both a hydrometer AND a refractometer it's possible to approximate an OG and ABV by calculating the difference between refract and hydrometer.

However as said if this was an extract kit, as long as you followed proper procedure (added the correct fermentables and had the correct volume), you can just assume the OG was what the kit said it should be.
You guys never cease to amaze me with your knowledge. I'm not new, by any means, but maybe sheltered. In any case, I always enjoy learning new info.
 

davidabcd

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Yeah it’s a northern brewing kit and I made slight changes such as adding fruits
You sound very experienced if adding fruit is slight for you. Slight for me is adding a half pound of steeping grain.
I do only extract. I did add fruit to a beer last year. It was good, the smell was phenomenal but the flavor was a bit dry so I had to back sweeten at bottling (add, stir, taste). Not a straight-forward endeavor.
 

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Yeah it’s a northern brewing kit and I made slight changes such as adding fruits
Assume you had the kit suggested OG of 1.042. It is difficult to get it wrong, unless you add too much water, and the FG was 1.014. That would give an alcohol by volume (abv) of about 3.7%.

Adding fruit will not make much difference. Assume it makes no difference. ....... If you really want to get into it, you might be surprised to find out that adding fruit usually reduces the ABV of a beer.
 

CJGreenleaf

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Assume you had the kit suggested OG of 1.042. It is difficult to get it wrong, unless you add too much water, and the FG was 1.014. That would give an alcohol by volume (abv) of about 3.7%.

Adding fruit will not make much difference. Assume it makes no difference. ....... If you really want to get into it, you might be surprised to find out that adding fruit usually reduces the ABV of a beer.

Adding fruit usually reduces ABV despite the sugars present in the fruit? Would adding a diluted white sugar solution counteract the addition of fruit? That's what we did. Should probably mention I'm ThatGuys's girlfriend. =]
 

Qhrumphf

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Adding fruit usually reduces ABV despite the sugars present in the fruit? Would adding a diluted white sugar solution counteract the addition of fruit? That's what we did. Should probably mention I'm ThatGuys's girlfriend. =]
I don't know if I'd say it reduces ABV. All depends on the water vs sugar content of the fruit. Or adding whole fruit vs puree vs juice vs concentrate.

For reference: https://www.law.cornell.edu/cfr/text/19/151.91

So for example, if you add apple juice (average 13.3 °Brix or ~1.054), and your wort was less than that, you're increasing the overall gravity. Otherwise you're effectively diluting it.

Plus fruit sugars tend to be highly fermentable and ferment to dryness, so even if you're lowering the overall gravity/diluting the wort you could still boost ABV.
 

ncbrewer

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I did add fruit to a beer last year. It was good, the smell was phenomenal but the flavor was a bit dry so I had to back sweeten at bottling (add, stir, taste).
I'm curious about how you back sweetened at bottling. Normally, any sugar added gets fermented and doesn't result in a sweet taste - just increased carbonation.
 

4of7

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Hey everyone,

I brewed a block party summer ale from northern brewing and I don’t think I boiled the wort hard enough but it’s been fermenting for 2 weeks and one week was colder temperatures so I got a heat pad to make it around 70F and it’s been at that for a week under a blanket for darkeness and warmth. I just opened it up and the potential ABV reads around 2% and it’s supposed to be a little above 4%. Now there any action from the looks of it with the yeast. How can I raise the ABV from this point?
To raise the abv.. you need more fermentable sugar..and yeast that is also available.. boil water and add dme.. let cool..add... keep Sanitation
 
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