Hydrometer Questions

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spacebiscuit

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Hi All,

I'm brewing my 3rd HB kit and I'm trying to address a few errors in previous attempts. One of which being the use of a hydrometer. I made my wort 24 hours ago and just now took my first reading which was 1.030.

I've since read that I should have taken it before adding the yeast, so will my reading be skewed having left it for 24 hours?

If I understand correctly this initial reading will give me my final ABV. I plugged the 1.03 figure into a calculator with a final gravity reading of 1.004 which gave an ABV of approx. 3.4%. I'd perhaps like my beer to be a little stronger, so should I add extra sugar (or can I) at this stage or am I mis-understanding something. If I can add the sugar how do I know how much extra to add. Presumably adding the extra sugar will increase (and reset?) the initial reading so is this a way of doing it?

When I transfer with FG at 1.004 does the fermentation process not continue in the pressure barrel, if so why aren't reading required from the barrel. Apologies if that is a stupid question. Finally should I add anything else to the brew at the point of transfer to the barrel.

Thanks in advance.

Bob:thumb:
 
Without taking the first reading before you added the yeast it is pointless putting it into a calculator, fermentation as started and would have been higher than 1.030

Where have you got the FG from?
 
What kit was it, did you make to the instructions or change anything like brew short and what does the box say the target ABV is? If it was a single can kit what sugar did you add?

If you work out what you did compared to the instructions it should ive you a good idea of what ABV you will get, although most kits I've done dont get as far as the target FG.

Also do a test of the hydrometer with water. It should read 1.000
 
the first, (pre-yeast) reading will provide you with your Original Gravity (OG) ;)

Simply Yes taking this reading 24 hours after pitching will give a false reading, by how much is uncertain, depending on the population you pitched (how many billion cells), and at what temperature the brew has sat.

As long as you followed the kits advice regarding any additional sugar to add, and the volume of water to use, you can be fairly confident that your Original Gravity WILL BE CLOSE TO TARGET, and you can use the expected OG printed in the kits instructions along with the final gravity you take prior to racking off into a PB.

Generally the Final Gravity the reading taken when primary fermentation has completed and all the available sugars in the wort have been consumed by the yeast. and is generally between 1.008 and 1.012 though again its totally brew dependent.. you could have an FG as low as 1.004 IF you used a lot of simple sugars like white table sugar or brewers sugar or brew enhancer, But even with a 1 tin kit and the cheapest nastiest 'brew enhancer' product I would still expect a FG of 1.008, but only time will tell on that front.

fermentation will continue in the pressure barrel or bottle IF a priming charge is used to condition the beer, generally 80-240g of white sugar is used for a 5 gallon (23l) batch, depending on how much condition is required, imho anything over 200g if using a PB is a waste as it should generate pressure beyond the prv should contain.

So in short, relax, your brew will probably be a fair bit stronger and finish with a slightly higher FG than you expect, and next time take the OG reading before the yeast get munching on the banquete you have prepared for em ;)
 
It's a learning curve, next time you will now to take a reading sooner
As it's a kit it will give u a ball park abv
You can still use the hydrometer to see when it's finished
And it will still be beer :thumb:
 
the first, (pre-yeast) reading will provide you with your Original Gravity (OG) ;)

Simply Yes taking this reading 24 hours after pitching will give a false reading, by how much is uncertain, depending on the population you pitched (how many billion cells), and at what temperature the brew has sat.

As long as you followed the kits advice regarding any additional sugar to add, and the volume of water to use, you can be fairly confident that your Original Gravity WILL BE CLOSE TO TARGET, and you can use the expected OG printed in the kits instructions along with the final gravity you take prior to racking off into a PB.

Generally the Final Gravity the reading taken when primary fermentation has completed and all the available sugars in the wort have been consumed by the yeast. and is generally between 1.008 and 1.012 though again its totally brew dependent.. you could have an FG as low as 1.004 IF you used a lot of simple sugars like white table sugar or brewers sugar or brew enhancer, But even with a 1 tin kit and the cheapest nastiest 'brew enhancer' product I would still expect a FG of 1.008, but only time will tell on that front.

fermentation will continue in the pressure barrel or bottle IF a priming charge is used to condition the beer, generally 80-240g of white sugar is used for a 5 gallon (23l) batch, depending on how much condition is required, imho anything over 200g if using a PB is a waste as it should generate pressure beyond the prv should contain.

So in short, relax, your brew will probably be a fair bit stronger and finish with a slightly higher FG than you expect, and next time take the OG reading before the yeast get munching on the banquete you have prepared for em ;)
 
I'm brewing my 3rd HB kit and I'm trying to address a few errors in previous attempts. One of which being the use of a hydrometer. I made my wort 24 hours ago and just now took my first reading which was 1.030.
I've since read that I should have taken it before adding the yeast, so will my reading be skewed having left it for 24 hours?
Yes, you should have taken it before adding the yeast. However, this is no big deal unless you're really interested in precisely how much alcohol is in your beer.
If you're brewing from a kit, and you've followed the instructions carefully about dilution and sugar addition (if any), then 1.030 is not going to be the original starting gravity (OG). Even for a low-strength beer the OG would be 1.040 or higher. After 24hrs fermentation will have reduced it - but if it is now fermenting vigorously then you'll have difficulty getting an accurate reading. And I wouldn't worry anyway, it's not going to affect the beer - just let it do its stuff :smile:

If I understand correctly this initial reading will give me my final ABV. I plugged the 1.03 figure into a calculator with a final gravity reading of 1.004 which gave an ABV of approx. 3.4%. I'd perhaps like my beer to be a little stronger, so should I add extra sugar (or can I) at this stage or am I mis-understanding something. If I can add the sugar how do I know how much extra to add. Presumably adding the extra sugar will increase (and reset?) the initial reading so is this a way of doing it?

Nope, the initial reading (OG) will only give you a guess at your final alcohol by volume (ABV). But don't worry too much - skip to the bottom of this paragraph if you like! The actual, rather than predicted, way that the fermentation proceeds will govern final alcohol content. For instance, I believe that your hypothetical FG of 1.004 is vanishingly unlikely. This is way too low for most styles of beer, especially from a kit.
To calculate ABV accurately, you firstly need an accurate OG (which you haven't got, forget about it for this brew), secondly an accurate FG, and then it helps to know what type of brew you've got. For instance, very high alcohol reduces SG. Lots of unfermentable sugars (say "sweet stout") increases SG. So it's not that precise.
Also, hydrometers are only accurate at the temperature they're calibrated for, and might not be that good anyway. Check that it says 1.000 in pure water at the right temp (often 20C)

But, if you've made the kit up right, put in the right sugar, the yeast has worked well, and your FG is in the region of 1.008 - 1.012 (depending upon the kit) then don't worry. It'll be about as strong as the kit claims.

When I transfer with FG at 1.004 does the fermentation process not continue in the pressure barrel, if so why aren't reading required from the barrel. Apologies if that is a stupid question. Finally should I add anything else to the brew at the point of transfer to the barrel.
Well, assuming the beer is transferred to barrel at 1.004 - and I'm confident it won't get that low, then no. No further fermentation, because there aren't any sugars left to ferment. The yeast has run out of food & stops (but doesn't all die). That's why you need to prime the barrel with sugar to get the yeast going again & carbonate the brew.

Looks like you need to read some pretty basic brewing info to get you up to speed. Try:
http://howtobrew.com/
Or any book by Graham Wheeler

Good luck & enjoy! :)
 
Many thanks for some really helpful replies guys.

The kit is a Geordie Scottish Export Bitter Kit, the can says 3.8% ABV so my incorrect calculation of 3.4% wasn't far off. I followed the kit's instructions exactly, adding brewing sugar (1kg).

I've just read the instruction again and actually it says to wait until a reading of 1.005 (sorry not 04 as I originally stated!) is achieved two days consecutively. It also says to add 2 1/2 oz of sugar (40 pint kit)
"dissolvd in about a pint of your beer then siphon in the remainder". Surely just adding the sugar to the barrel will dissolve it anyway? Would there be any benefit in using a beer kit enhancer sugar at this stage if I didn't use it the primary stage?

Found a book on my book shelf by John Palmer - will have a read.

Thanks again!

Bob.
 
When it says to take a reading before adding the yeast I don't think it really makes any difference to the reading but rather it'll be harder to take a reading with yeast clung to your hydrometer and you'll be removing yeast when you take the hydrometer out.

What I would emphasise is that you stir up all the thick syrup at the bottom of the fv to get it thoroughly mixed with the water, otherwise any reading you take will be much lower than it should be as it wont take into account any sugars which aren't mixed and are sat at the bottom.
 
Surely just adding the sugar to the barrel will dissolve it anyway? Would there be any benefit in using a beer kit enhancer sugar at this stage if I didn't use it the primary stage?

Hi!
If you prime your PB with dry sugar there is a good chance that some of it will not dissolve. Always dissolve the sugar when batch priming; it won't hurt to use a little boiling water, dissolve the sugar then allow the solution to cool to the same temperature as your beer before putting it into the PB and transferring your beer on top of it.
I wouldn't add any extra fermentables to your FV once fermentation is under way. If you have overlooked taking a reading for OG (which many home brewers have done at some point) then proceed without knowing an accurate FG figure. As Cqr has pointed out above, it's beer - stop worrying and sup up! Put it down to experience.
 
While the sugar will probably dissolve and disperse throughout the bulk if added dry, There is a slim chance that sediment may drop on top of the sugar before it can dissolve fully and effectively seal if off from the bulk. Rare, but it can happen..

dissolving and mixing throughout the bulk is also 'best practice' when bottling to ensure even distribution of the priming charge.

brew enhancer and other such products are a RIP OFF, they contain basic simple sugars which are going to fuel alcohol production but provide zero mouth feel or body to the brew, and will impart a dry thin quality to your brew.
some may contain a dash of spraymalt or DME but not in sufficient volume to impart any body or flavour, and nothing to justify the High price tag applied.

white sugar is basically the same as any brew enhancer product, being a construct of 2 of the simple sugars used (glucose and fructose iirc).
And Yeast can break down white sugar (sucrose) easily,

The yeast can eat the simple glucose and fructose sugars without any 'breaking down' so can theoretically consume a simple sugar liquor a bit quicker. But few brewers are concerned about knocking 20 minutes or an hour off the duration of the primary fermentation period.


wow an expected FG of 1.005!! That is a bit on the 'thin n dry side..' while taste is a very subjective thing imho you may find beer kits that come with 2 x tins of LME may produce a more flavoursome brew, as the Malt extract contains a soup of simple and complex sugars the most complex of which remain in the beer throughout fermentation and provide the finished brew with body, mouthfeel, and malty flavour..
 
What kit was it, did you make to the instructions or change anything like brew short and what does the box say the target ABV is? If it was a single can kit what sugar did you add?

If you work out what you did compared to the instructions it should ive you a good idea of what ABV you will get, although most kits I've done dont get as far as the target FG.

Also do a test of the hydrometer with water. It should read 1.000

Ale, I recently bought a new hydrometer after breaking my original one. I suspected that it wasn't giving me a proper reading so I tried it in water as you suggested and my suspicions were confirmed, 1.006 reading.

Thanks for the advice.
 
Just a quick update, my brew has been in the fermenting bin for a 7 days, I just took another reading and I'm still getting 1.030 which indicates that nothing or very little has happening the past week. The bin has been left at room temperature and undisturbed.

Any advice or tips? Should I try moving it closer to the radiator perhaps?

Thanks,

Bob.
 
1. If you punch your 1.5kg kit can contents (as LME) plus 1kg brewing sugar into the calculator it gives an OG of 1.036, assuming your brew vol was 23 litres. I use this calculator and find it compares well with my hydrometer reading.
http://www.brewersfriend.com/homebrew/recipe/calculator/
Your reading of 1.030 after a day compares well with the estimated OG reading allowing for the primary to get going.
2. If you add 2.5oz (about 70g) of sugar to your PB as suggested in your instructions you might find it a little undercarbed. I would go for about 85g. In the end its up to you.
3. I never bother with dissolving sugar in water. I just add it using my brewing teaspoon to bottles through a funnel, or add it direct to my PBs. I give the bottles or the PB a gentle swirl and let things take their course. Doing it this way I have never, in all my years of homebrewing, ever seen any sugar that failed to dissolve and not get gobbled up by the yeasties, before i got to drink it.
4. If your brew has stuck, usual advice is to get it into a warmer place and /or give it a gentle stir or a swirl without entraining air into the liquid. However seeing the SG is so high, and with comments in {1} above about OG aside, are you actually sure it started fermenting in the first place? If you can't get it going again then its time to repitch with another yeast. Try a Wilko Ale yeast if you have nothing else.
 
What temperature is the brew sat at? a gardeners min/max thermometer is a useful tool to sit by the FV to indicate the range of temperatures your beer sits in durring the fluctuations of the day.

if the temperature is below the range of temperatures suggested in the kit instructions for fermentation perhaps move it slightly nearer to a heat source, but you may find simply insulating the bucket may well work too as when active the yeast will give off some heat through activity. and if sat on a cold stone or tilled floor slipping a bit of 2 wall cardboard to insulate the brew from the cold floor may help too.

generally speaking its simple to ferment at the cooler end of the temperature range suggested for the yeast you use, at the warmer end of the range the yeast may work faster But they may also create unwanted flavours from easters and fussels which are not generated so much at lower temperatures.
 
I followed some advice in previous replies and moved the fermenter closer to a heat source, I swirled the wort and then stirred it a little without adding any air. It's now been 14 days in the fermenter and I'm getting a reading of 1.010. Allowing for a margin of error in my reading and perhaps an unrealistic/unachievable target FG (unless brewed in a professional environment) of 1.005 would now be a good time to move the WORT to the pressure barrel or should I hold out a little longer?
 
Hmmmm. ..what exactly are you brewing?I ask as my Youngs AIPA kit instructions said it would go down to 1006..and it did. But...stability is what you are looking for,over a few days,so try it a few days on the run...if it stays at say 1010 then it should be done. Leave it for another week if you're not sure..it won't harm it.

Cheers

Clint
 
the general rule of thumb is when you read a steady gravity reading close to the expected FG for 3 consecutive days with no drop at all, then its probably finished, 4 points above target is on the margin of close to FG imho so keep taking readings and see ;) fingers crossed the FG is closer to 1.010 for you, the brew will have more body n mouthfeel to it.

for future reference, dont swirl the brew to help mixing in at this stage, while its covered with a protective layer/blanket of co2 swirling can invoke a vortex to draw air in, its the premise behind using a stir-plate with a yeast starter as the vortex is efficient at exchanging the co2 expelled by the yeast with air to feed the growing population with o2. However at the end of fermentation o2 is less desirable as it can oxidise the beer, and as the yeast population has already peaked o2 isnt useful to them anymore. a gentle stir with a spoon under the protective co2 layer is ample 'rouseing' ..
 
Should have mentioned, the hydrometer has what looks like a tide mark around the 1.010 readig which I think suggests that it has been sat at the current gravity for a few days - I had left it alone for 7 days.

Fil - I only stirred and swirled it last week when after a week the gravity hadn't dropped since I kicked the brew off.

Also - I returned to the fermenter a few hours after taking the reading tonight and I could hear a hissing. Initially thought it was my radiator before realising it was my brew. Should I open the lid to expel this air or leave it be. The lid was also bulging a little. Is this a good sign?

Thanks.
 
Ahh you have the hydrometer sat in the brew.. pull it wash it sanitise it (dont use off the boil water it can melt the glue holding the gradient tube of paper in place) and if needed replace. yeast cells clinging to the hydrometer may effect its reading, and a marked ring could be creating an optical illusion, take a digital photograph of the reading and blow it up on your puter or phone to read..

drawing off 70-80ml of brew to measure in a trial jar can be a pita if you dont have a tap on your FV, but can be easily done with a sub �£1 turkey baster, easy to clean and sanitise just remeber to squeeze air out of the bulb prior to submerging the tip to draw the sample ;)

This way you needent sanitise the hydrometer and you have the added bonus of a wee sample of brew to taste and judge its progress. (Never be tempted to return the sample to the batch)
Tasting is the best way to follow the progress of the brew, before pitching the yeast its a nice sweet malty taste, then as the brew progresses the sweetness drops off leaving a varying depth of malt and the hops start to show..


The problem i have with leaving the hydrometer in the bucket/FV is when you spin the hydrometer your fingers could leave something unwanted behind, And craning ones neck to read the reading at the meniscus (liquid level) can position ones bonce directly over the beer and everyones head is alive with microlife, bugs n wild yeasts galore, even slapheads like me. and all too many of us do an involuntary head scratch when concentrating ....

Brewing is basically a numbers game, we provide a huge bucket of warm sweet wort a veritable banquet for all the microlife that lives on n around us, And we stack the odds in our favour with good cleanliness and sanitation and by pitching a population counted in the billions of our chosen microlife (yeast) so they have the advantage to out eat and thrive above anything else. But its best not to take any unnecessary risks ;)

dont mean to come across all preachy, i just do it naturally..

and if the brews not warmed up to the point its steaming, then Yes the increased co2 pressure is a +ve sign and you could well be on track for hitting the expected FG or getting a bit closer at least..
 
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