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Og Fg Calculations Flawed? Too Achoholic?

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phoenixdigital

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Now we have been brewing for quite some time and have noticed that our beer is definitely way stronger than what the calculations are saying.

We measure the OG with both refractometers and hydrometers then measure the FG and plug it into the standard equations.

OG generally 1.050
FG generally 1.010

Which should mean a beer of 5.25%.

Note we are kegging and force carbing so there is no extra alcohol content from priming sugars.

Also if it makes a difference we are making all grain beers.

It was pointed out by a few friends on the weekend that drinking 3 pints of 5.25% beer from the pub over the space of 2 hours would leave you with a buzz. However 3 pints of our homebrew gets you noticeably drunk. So what is different here?

One suggestion was maybe dialectyl if that can get you drunk?

Is there any other form of testing that can be done by me? I am even keen to spend a up to $100 to get this sent to a lab just so I can get a definitive answer.
 

bum

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Dunno how accurate they are but search for a "alcoholmeter" on eBay. You'll be able to grab something much cheaper than $100.
 

Maheel

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maybe your hydro / refrac is out ?

maybe do a test in water and maybe a sugar water mix of known proportions to check it ?

maybe the pub is watering down the beer....
 

Yob

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Psychosomatic probably. If all things are equal then the only other factor is you.

Enjoy it.

I need to get one of those alcoholmeter thingamies one of these days.. and another thermometer <_<
 

dougsbrew

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Dunno how accurate they are but search for a "alcoholmeter" on eBay. You'll be able to grab something much cheaper than $100.

you will find that alcometers are only good measuring alcochol to water solutions, beer has too much in it to be of a valid reading.
 

bum

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Ah. Sorry, OP.
 

yum beer

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Its all in the numbers.
Straight up you are drinking more alcohol with your home brew.
By my calculations, using your figures, over 3 pints:
home brew - 95ml alc.
pub beer - 83ml alc. given 4.6% on tap...give or take.
thats about 1/3 a pint extra strength in the home brew.
Also I calculate your alc at 5.4%, that adds a little extra.
And perhaps the home bres go down a little quicker than they do at the pub, i know I drink faster at home then I do when Im out.
 

phoenixdigital

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Its all in the numbers.
Straight up you are drinking more alcohol with your home brew.
By my calculations, using your figures, over 3 pints:
home brew - 95ml alc.
pub beer - 83ml alc. given 4.6% on tap...give or take.
thats about 1/3 a pint extra strength in the home brew.
Also I calculate your alc at 5.4%, that adds a little extra.
And perhaps the home bres go down a little quicker than they do at the pub, i know I drink faster at home then I do when Im out.
I have tried to justify the level of intoxication based on all of those factors. But the results are quite obvious amongst all of our friends with the same level of intake.

Maybe we should start brewing 1.045 beers and see what happens.
 

bum

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$10 says you don't get as pissed.

Worst experiment ever.
 

phoenixdigital

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Found a pretty simple method of calculating it.

http://courses.chem.indiana.edu/s117/docum...centalcohol.pdf

Well it would be simple if I had the lab equipment.

Could be an excuse to buy a flask for making starters.

Alternatively another way would be to buy the gear that people use for making spirits and instead distill out the alcohol from a bottle of beer.
 

MHB

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I have a personal theory about this (its been talked about on lots of forums over the years)
Home brew contains yeast, and lots of other proteins and fatty acids that are mostly stripped out of commercial beer during production.
It turns out that quite a few of the chemicals are involved in or are cofactors in the metabolisation of alcohol, what I think might be happening is that the presence of all the beneficial bits in home brew buffers the rate we feel the effect and generally leaves us feeling better the next day.
I think you get just as pissed is just a longer softer ride, with a smaller drop off the cliff the next day.
Mark
 

pcmfisher

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I have a personal theory about this (its been talked about on lots of forums over the years)
Home brew contains yeast, and lots of other proteins and fatty acids that are mostly stripped out of commercial beer during production.
It turns out that quite a few of the chemicals are involved in or are cofactors in the metabolisation of alcohol, what I think might be happening is that the presence of all the beneficial bits in home brew buffers the rate we feel the effect and generally leaves us feeling better the next day.
I think you get just as pissed is just a longer softer ride, with a smaller drop off the cliff the next day.
Mark

Wouldn't that mean we feel less pissed when drinking home brew?
 

MHB

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Actually Yes, and that is what most people suggest is the case teach me to read the OP rather than glance at it.
If you are getting more hammered on Home Brew, I would really be looking at the gravity readings because in general its the alcohol that does the hammering.
Mark
 

phoenixdigital

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Yeah another confirmed casualty from the weekend. I think we should start brewing lighter cause people have started bringing their own beer to our events so they dont get too smashed.

An SMS from a friend on Sunday.

Holy Shit ur beer has some potency! I was absolutey wankered when I left last nite, couldn't even string a few words together to the cabbie. Fucken hell. I was in bed by 9.30. Either I'm outta practice or ur brews about 10 percent or more.
I also am keen to get the lab equipment mentioned above so I can confirm percentages at some stage.
 

Ross

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Phoenixdigital,

We have a professional alcohol tester (not Anthony) in the brewery here. you are welcome to bring in a sample for testing.

We'll need approx 50ml.

Cheers Ross
 

phoenixdigital

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Phoenixdigital,

We have a professional alcohol tester (not Anthony) in the brewery here. you are welcome to bring in a sample for testing.

We'll need approx 50ml.

Cheers Ross
Thanks for the offer Ross. Next time we are out your way I will bring a sample.

Definitive results from an official piece of equipment would give me peace of mind.
 

black_labb

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Keep in mind that your liver processes roughly 1 standard drink an hour, so drinking 5 standard drinks in 2 hours means you are effected by 3 standard drinks. If you drink 4 standard drinks over 2 hours you have only 2 standard drinks effecting you. so in this case a 25% increase of standard drinks consumed turns into a 50% increase in sillyness.

Also hops are a sedative related to cannabis, if you are brewing hoppier beers people will tend to mellow out more than less hopped beers which includes most commercial beers.
 

phoenixdigital

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Keep in mind that your liver processes roughly 1 standard drink an hour, so drinking 5 standard drinks in 2 hours means you are effected by 3 standard drinks. If you drink 4 standard drinks over 2 hours you have only 2 standard drinks effecting you. so in this case a 25% increase of standard drinks consumed turns into a 50% increase in sillyness.
That is one of the best explanations to date and makes a bit more sense. The session started about 4ish and people started to drop around the 9pm mark. Which is quite unusual for our group who can quite easily stay coherent and conscious for 8 - 12 hours.

Also hops are a sedative related to cannabis, if you are brewing hoppier beers people will tend to mellow out more than less hopped beers which includes most commercial beers.
Another good explanation too. There wasn't too much mellow but it would def add to the messy. I am a massive fan of the hoppy beers so this would also affect it.

I am glad you mentioned that because I thought there may have been some other ingredient or chemical from the brewing process which was introducing something 'extra'.
 

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