When to measure OG?

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Harbey

Harbey

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I'm all set to start my first brew and I've written down all my instructions / to do list etc.
One thing is still bothering me though - when do I measure the OG and what if it's out? My recipe says I should have 28ltrs of wort for the boil and that the OG should be 1.045. So I make sure I have my 28ltrs; do my 60 min boil; cool the wort; and then, just before I put it in the FV, I take the OG reading. Is that correct? My question, however, is what if I'm out and how much out can I be? My (limited) understanding was that if I was too high on my OG I should add more water. And if I was too low, I should boil some off. But isn't it too late by the time I've cooled the wort?

Sorry - I'm sure this is a really silly question, but it's the one piece of the puzzle that is still bothering me (other than carbonation, but I can wait to worry about that can't I?) .
 
Harbey said:
I'm all set to start my first brew and I've written down all my instructions / to do list etc.
One thing is still bothering me though - when do I measure the OG and what if it's out? My recipe says I should have 28ltrs of wort for the boil and that the OG should be 1.045. So I make sure I have my 28ltrs; do my 60 min boil; cool the wort; and then, just before I put it in the FV, I take the OG reading. Is that correct? My question, however, is what if I'm out and how much out can I be? My (limited) understanding was that if I was too high on my OG I should add more water. And if I was too low, I should boil some off. But isn't it too late by the time I've cooled the wort?

Sorry - I'm sure this is a really silly question, but it's the one piece of the puzzle that is still bothering me (other than carbonation, but I can wait to worry about that can't I?) .
Click to expand...
If you are significantly under you can always chuck in some dried malt extract.
 
I always take my OG after it has been cooled but before I add the Yeast Nutrient and the Yeast.

As I am never trying to meet a target, the OG is taken so that I can get an accurate ABV. On those rare occasions when I actually hit the OG predicted by BrewersFriend I give myself a pat on the back ... athumb..

... but recognise that hitting the predicted OG was just a happy accident! clapa
 
If you really want to get your OG bang on, you could mash with the normal volume of water but boil with a bit less. Then you hope your OG is too high, which you can dilute with water in the FV. You just might end up with slightly more or less beer, depending on how efficient the mash was.

Remember that the hydrometer reading might need to be adjusted for temperature (use the calculator via the Calculator link at the top).

If you want to get the right volume, at the right OG, with the right bitterness, the right colour, the right dry hop profile, the right FG and the right carbonation...
 
Harbey said:
Thanks everyone. I'm over thinking it aren't I?

Right, I'm going to go give everything a final check and clean and try to find the courage to get started. I'll post my results.
Click to expand...

Better get started soon if you want to be done by bedtime!

Good luck!!!
 
Hi,
I'd measure gravity at the start and finish - 15 of the boil,(cool to 20°c and take a reading on both of these, and return the measured wort to the boil) then adjust with liquor accordingly ; and again after cooling, before pitching the yeast,
Cheers
Edd
 
Harbey said:
Ha. I'm optimistic clapa

One last(ISH) question. If I add water/wort to the FV after the boil, shouldn't that be boiled too, to avoid contamination?
Click to expand...
Yep, Any liquoring back should be done in the boil, though
I'd reserve a bit of extra brewing liquor from the mashing and add it at the end of the boil, maybe extend the boil to 1:15-1:20,
Cheers
Edd
 
Harbey said:
One last(ISH) question. If I add water/wort to the FV after the boil, shouldn't that be boiled too, to avoid contamination?
Click to expand...

I'll disagree with Edd on this one and say it won't matter. I've always topped up with simple tap water and never had an issue.

If you were worried, you could top up with water boiled in the kettle without the need to cool. You'd just have to make sure you're at the right temp before pitching the yeast.
 
Well, for better or worse, I've started. Got my water (25ltr) up to 70 then added the grain. Wasn't expecting quite such a drop off in temperature, went down to about 62 by the time i added all the grain (maybe being too slow adding it). I'd put a colander over the element of my Peco, so warmed it back up to 67 and then got it wrapped up. I'm going to give it a mix and check the temp after 30mins. Smells nice so far.
 
I agree with you Bezza any liquoring back should be done in the FV using the relevant calculator on Brewers Friend or similar.
 
If you are bothered about hitting the OG target, an alternative to adding boiled cooled water is to use bottled water. Tesco Ashbeck is often used because it has a very low mineral content (important for pale beers) and is cheap, I have also used Asda Still water.
 
Mash done. Bag out and sparged (sort of) in a second bucket giving me enough wort to hit the 28ltr (just about). Waiting for the boil now.

I think I've covered about 6mile so far making trip after trip to and from kitchen to brew room (opd out-house). Will have earned a pint by tonight!
 
First AG brew you just focus on the process and take the numbers. They are what they are and you have ages to think about them later. Then you think what you might do next time.

Sort of - crawl, walk, run, to use an analogy.

Don't over think on the day, just do it.
 
I measure several times with the refractometer, just to have water in the right temperature standing by, or maybe some sugar. But the important measurements with the hydrometer are just before pitching, and just before bottling.
 
So I'm done acheers..
Beer in the FV and everything cleaned out.

Really happy with how things have gone. Ended up with just short of 24ltrs and OG of 1.047 which seems pretty close.

My only worry is the amount of cloudy, nasty looking sederment that seems to be floating around in the brew (your cue to say "don't worry, that's perfectly normal and will clear by the time you bottle it"). I was expecting a bit, but there's loads (in my opinion). Anything to worry about?
 
A lot of cloud? It's not really normal to have a lot, but you will improve and it will be clearer. There's coldcrash and racking to bottling vessel that will take care of a substantial bit of floaties.

Now start worrying about how it will seem finished in 4 days but it still needs 10 more days to finish! Aaargh!
 
Pfft, don't worry about it. It'll settle during fermentation and cold crashing. Many people on here make no attempt to filter when getting into the fermentation vessel. The only difference it'll make at the end of the day is the amount of crud left in the FV when you bottle.
 

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