Pulling a sample vs putting the hydrometer in the bucket.

[slym2none]

I can't help but nitpick here... You're actually measuring to 4 sig figs, unless, of course, you're measuring dry wine, where you'll likely be under a 1 OG...

Nitpick back - he did say "significant" figures, which means for us beer brewers, we don't really count the whole number (1), just those after the decimal.

 

[brewcat]

Since I started kegging my fg sample is usually my first pour. I might use a thief and test jar when dry hopping if I'm unfamiliar with the yeast.

Umm...Carbonation? That will throw off your reading. Maybe I should assume you stir the sample to release the CO2?

I use a thief and test jar. I take my reading when I'm ready to bottle/keg. I want an accurate reading. Otherwise, why bother? Seems it is easier to draw a sample than mess with dropping a hydrometer in a bucket.

Accurate readings are very important & useful for designing recipes.

 

[JawZziff]

I think Best Practices, at the risk of over using that phrase yet again in another industry, is the proper way of looking at the brewing industry now. What was considered dogma 10 years ago is being found to be not quite right or maybe just plain wrong--at least for the homebrew community when compared to pro-brewing. We are finding that some things should not be considered dogma, but rather "best practices" based on present knowledge and technology, and could or will change in the future. Even within the home brew community "best practices" can be different depending on Volume (1, 3, 5, 20 gal, etc,) and BIAB. It's different depending on the equipment (1, 2, 3, vessel) automated vs manual, gas fired vs electric, the list goes on. Best practices for a beginner could and in some cases are different than an advanced home brewer. Just saying...

Sorry, but I don't have time to give examples, but someone else please feel welcome to write a proper article on this subject, or a book.

lol that is a big ol can of worms now isn't it?

 

[Stillraining]

We make simple things to hard sometimes.

 

[TurnipGreen]

There's a lot of science and numbers flying around here.

I use a thief. While I do take a gravity reading, when I pull a sample I do it just as much to give a taste. Where's the fun if you just get a number and no beer?

 

[sompls]

There's a lot of science and numbers flying around here.

I use a thief. While I do take a gravity reading, when I pull a sample I do it just as much to give a taste. Where's the fun if you just get a number and no beer?

You seem to have a handle on things just fine and we should all take a page out of your book...it's supposed to be fun...and beer!
p.s. when in doubt, @Gavin_C knows his stuff so a person could do way worse then follow his suggestions. If you're into science and stuff

 

[Pkrd]

Umm...Carbonation? That will throw off your reading. Maybe I should assume you stir the sample to release the CO2?

Gargle and spit.

 

[max384]

Nitpick back - he did say "significant" figures, which means for us beer brewers, we don't really count the whole number (1), just those after the decimal.

https://en.m.wikipedia.org/wiki/Significant_figures

 

[muels]

This is the reason I posted this in the beginners section! Thanks all.

Honestly I'm not all that concerned with the accuracy unless it's something completely different that I have never brewed or a new yeast. I have my process down pretty well and can pretty much tell where most of my stuff will finish within a point or two. I'll normally take a reading in the bucket as I'm getting ready to cold crash just so I can avoid any surprises.

I was really just hoping to spark a discussion and get a few pros and cons that may give me something that I hadn't thought of or read yet.

I also agree that Best practices may be a bit different for beginners and folks with more experience.

Thanks again.

 

[masskrug]

I just use airlock activity as a means to tell gravity. It's a very accurate way to tell where fermentation is at.

Count the bubbles for 6 seconds and then multiply that by 10. This is your Bubbles Per Minute (BPM) reading. This number should correlate to the last two digits of your gravity. For example, if your BPM = 20 then your gravity is 1.020. :hs:

 

[passedpawn]

Count the bubbles for 6 seconds and then multiply that by 10. This is your Bubbles Per Minute (BPM) reading. This number should correlate to the last two digits of your gravity. For example, if your BPM = 20 then your gravity is 1.020. :hs:

^^ he's kidding, noobs!

 

[beerwheel]

So can you pull a pint or so from the fermentation bucket after the yeast is added and ferment that is a bottle/jar and use that to test rather than opening the bucket/carboy to pull a sample?

 

[Pkrd]

So can you pull a pint or so from the fermentation bucket after the yeast is added and ferment that is a bottle/jar and use that to test rather than opening the bucket/carboy to pull a sample?

This is called a forced ferment test. If you keep it warm and swirl now and then it should reach FG in a few days. This is the lowest FG you can expect to see in your fermenter.

 

[Homercidal]

So can you pull a pint or so from the fermentation bucket after the yeast is added and ferment that is a bottle/jar and use that to test rather than opening the bucket/carboy to pull a sample?

This is not for testing the current gravity of the main fermentation, but it could be useful to tell you what your expected FINAL gravity WILL BE eventually.

The portion kept separate is generally fermented warmer - conditions that the yeast LOVE, but isn't generally as good for flavor. The sample will ferment faster and get to completion sooner.

You can measure that, just to get an idea of how low your main ferment is going to get. You can then measure your main ferment and when it reaches the same gravity as the sample (or very close) you can consider it "finished".

I personally like to check gravity of the main ferment, and when it gets mostly done, move it to a warmer location to finish. The higher temps aren't a problem because almost all of the fermentation is complete. The warmer temps encourage the yeast to finish their party, and clean up after themselves.

The other option is to simply leave the fermentation at the same temp and wait a bit longer. But that's so hard to do when you first start out and have no pipeline.

 

[beerwheel]

Thanks, that is great explanation. My current plan is to leave the brew in the 6.5 glass primary for three weeks (expiring tomorrow) and transfer to 5 gal glass secondary this weekend and pull a sample at that point. It's a 6% dry Irish ale and hasn't bubbled for 10 days at a constant 67. I use a water bath and will ferment my draw in the same environment and the main batch next time. I don't want to draw samples from the fermenter so I hope that will work.

 

[Kee]

It's worth mentioning that hydrometers are notoriously inaccurate (yes, you can get an idea how to adjust after checking the SG of water). But in the real world being a point off doesn't matter so much as knowing the beer is done.

I would never leave a hydrometer in a brew bucket, but only out of concern that the hydrometer may break.

I take multiple readings (usually) but if the krausen has fallen, the beer is clear, you've hit the upper range of the yeast's recommended temperature range, and the FG is around what it should be, I call it done. And then give it two or three more days, just in case.

 

[ViciousFishes]

Count the bubbles for 6 seconds and then multiply that by 10. This is your Bubbles Per Minute (BPM) reading. This number should correlate to the last two digits of your gravity. For example, if your BPM = 20 then your gravity is 1.020. :hs:

Then, you actually need to divide the last two digits by 2 to get to true BPM. In this example, you'd have a nice dry finish of 1.010 in BPM (bupkis per minute, according to 18th century chemist, Leonardo da Bupkis).

 

[ame]

My brew bucket has a tap at the bottom. I use this to pour a sample, which I transfer to a measuring cylinder. I put my hand over the top of the cylinder and shake it well to get rid of the dissolved gas. When that's done I take a reading with a hydrometer.

Then I drink the sample.

 

[NoIguanaForZ]

I ferment in glass. Getting the hydrometer back out could be...dicey. Otherwise I'd probably have tried this.