Leaving a gravity sample for a week?

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Bashley

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Hi All

I broke my hydrometer last week whilst brewing but I took a sample anyway, added it to my tube and wrapped cling film around the top; I should receive my new hydrometer tomorrow. Will the reading still be accurate if it's been sitting around for a week? Cheers!
 
Hi All

I broke my hydrometer last week whilst brewing but I took a sample anyway, added it to my tube and wrapped cling film around the top; I should receive my new hydrometer tomorrow. Will the reading still be accurate if it's been sitting around for a week? Cheers!

It will tell you the SG of the sample as it is now, if you check the calibration afterwards. The new hydrometer will read 1.000 for water at 20C.

It will give an indication of what it may have been a week ago, but a lot can happen to a small quantity of beer in an environment that is not sterile., over the course of a week.
 
Hi All

I broke my hydrometer last week whilst brewing but I took a sample anyway, added it to my tube and wrapped cling film around the top; I should receive my new hydrometer tomorrow. Will the reading still be accurate if it's been sitting around for a week? Cheers!
So the tube is clean? -ish? If it's a representative sample then fermenting will have continued and the sample now would equal the brew now. Would/should but whatever. And then again what @Slid said: bounce the hydrometer in a beerglass and see if it reads 1000.
 
So the tube is clean? -ish? If it's a representative sample then fermenting will have continued and the sample now would equal the brew now. Would/should but whatever. And then again what @Slid said: bounce the hydrometer in a beerglass and see if it reads 1000.
I'm a noob so I could be wrong here but the sample was taken before I added the yeast. So I can't see how it would be fermenting at all. Am I missing something?
P.S The glass tube was sanitized.
 
If it was taken pre pitching then it should give you a good indication.

If however any wild yeasts or bacteria have got in and are munching the sugar, then the gravity will reduce giving you an untrue reading.
I'm not too clued up on this but I believe all or nearly all wort will have some form of contamination, but the prompt pitching of a healthy beer yeast will win the fight and kill off the competition (wild yeast and bacteria) with the alcohol it produces. That's why after a week without "proper" yeast, the reading may not be what it was a week ago.

It's certainly worth reading the sample to see what it is. You'll never be 100% certain if it's 100% true but it'll not do any harm.
 
If his happens to somebody else then get the sample somewhere cold or even freeze it then it'll halt any fermentation so you could do that until you get your hydrometer.

Bashley, do you have the inventory for the beer - you could get a fair estimate from brewing software, too, and then double check with the reading you do get.
 
I'm a noob so I could be wrong here but the sample was taken before I added the yeast. So I can't see how it would be fermenting at all. Am I missing something?
P.S The glass tube was sanitized.
In that case there will be no fermenting, I stand corrected.
 
If his happens to somebody else then get the sample somewhere cold or even freeze it then it'll halt any fermentation so you could do that until you get your hydrometer.

Bashley, do you have the inventory for the beer - you could get a fair estimate from brewing software, too, and then double check with the reading you do get.
I guess it doesn't matter too much. It's a session IPA recipe from brewdog and I imagine if I leave it for 10 days, 1 week dry hop I'll be all good.
 
Btw, do people ever take a gravity reading directly after pitching the yeast. It seems strange to me because you're essentially wasting yeast - I don't get it.
 
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Ahh. Forget about hydrometer nonsense (they all break eventually).

Take out measured amounts of finished beer - you may need an "observer" for this technique. Every ten minutes drink down one of the measured samples. Record when you fall over. Compare to beer of known strength (you may need to repeat test on another day). That should give you an idea.

Hang on... (What now...). Okay, seems I've said something wrong again.
 

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