Stop That Lager!

[scarper11 (Pinski)]

@denny

@yso191

Very, very interesting!  I have been assuming that the refractometer was the more accurate of the two, including the conversion in BeerSmith to get FG/ABV.  I may have to buy a hydrometer.  Using a hydrometer means increasing one’s batch size by how much?  I assume a minimum of two tubes of wort/beer.  What does that equal?  right now I make 5.5 gallon batches.  Might just take it to six as I’d rather have too much than too little.

It takes me 8 oz. for each hydro reading.  Although, after the beer is fermented I take 14-16 oz. samples.  After I get the reading I put the samples in a 20 oz. PET bottle with a carbonator cap.  Hit it with 30 PSI, put it in the freezer for 45 min., and I’ve got a cold carbed sample.  I also make 5.5 gal. batches.

+1
This is my favorite thing about hydrometer samples!
Accurate readings post fermentation is a close second. I’ve been taking both refractometer and hydrometer readings for my last few batches at various stages of fermentation and entering the readings into a spreadsheet. After a few more batches I’ll start charting the results to see what sort (if) a pattern emerges. I hope to be able to come up with a close correction factor for my refractometer readings post fermentation and maybe a better understanding of why it varies if the results are not consistent.

[jeffy]

I can also recommend the late Gregg Noonan’s book, Brewing Lager Beer.  I have the old version, before it was “New.”  It was the first book I bought that helped me with technical all grain brewing issues and I used it as reference for many years.  It is still an excellent resource.

[denny]

So if you mashed from 150 down to 147 for an hour you definitely mashed dry.  No surprise then that you are below your estimate FG.

I heard this is a good book to read for lagering.

Amazon.com

I bought it but since im not set up to lager i havent bothered yet with all the other material(a bookshelf worth) id like to plow through.

Cheers,
Jeff

I’d give that book a solid “Meh” in regards to homebrewing.  It’s really aimed at commercial brewing.  Interesting info and science, but way over the top for most of us.  Noonan feels like every mash needs to be decocted.  In addition, it’s getting a bit long in the tooth in regard to ingredients.

[a10t2]

@yso191

I have been assuming that the refractometer was the more accurate of the two, including the conversion in BeerSmith to get FG/ABV.

At the very least, you should use a better tool.

http://seanterrill.com/refractometer

In my own brewing, I’ve found that I can get precision about on par with a cheap hydrometer (standard deviation of about one “point”). A lot of people haven’t had such good results. To be honest, I suspect it comes down to most people not being as anal about their calibration and measurement technique.

[denny]

@a10t2

A lot of people haven’t had such good results. To be honest, I suspect it comes down to most people not being as anal about their calibration and measurement technique.

I’m one of those “lot of people”.  Got any tips on calibration and use?

[hopfenundmalz]

@denny

@a10t2

A lot of people haven’t had such good results. To be honest, I suspect it comes down to most people not being as anal about their calibration and measurement technique.

I’m one of those “lot of people”.  Got any tips on calibration and use?

Zero with RO or distiller.

Make a 10% solution with table sugar and RO water, it should read 10 Brix. You can also make enough solutions of different concentrations to plot a curve. Use the solution to check your hydrometer while you are at it. It helps if you have a gram scale for the sugar and a good way to measure the water volume.

Sean may have better techniques.

[denny]

@hopfenundmalz

Zero with RO or distiller.

Make a 10% solution with table sugar and RO water, it should read 10 Brix. You can also make enough solutions of different concentrations to plot a curve. Use the solution to check your hydrometer while you are at it. It helps if you have a gram scale for the sugar and a good way to measure the water volume.

Sean may have better techniques.

Thanks, Jeff.  I already do the first one.  I’ll try the second.  I assume that’s 10% of the water weight as sugar?  For example, 100 gr. water and 10 gr. sugar.  Or is it 90 gr. water and 10 gr. sugar?

[hopfenundmalz]

@denny

@hopfenundmalz

Zero with RO or distiller.

Make a 10% solution with table sugar and RO water, it should read 10 Brix. You can also make enough solutions of different concentrations to plot a curve. Use the solution to check your hydrometer while you are at it. It helps if you have a gram scale for the sugar and a good way to measure the water volume.

Sean may have better techniques.

Thanks, Jeff.  I already do the first one.  I’ll try the second.  I assume that’s 10% of the water weight as sugar?  For example, 100 gr. water and 10 gr. sugar.  Or is it 90 gr. water and 10 gr. sugar?

It is a 10% solution, so 90 gr water and 10 gr sugar.

[fejjgw (Jeff M)]

Kal Over at TEB put this together.  Might help answer some of your questions?  Might raise a few more even!

http://www.theelectricbrewery.com/forum/viewtopic.php?t=26975

Cheers,
Jeff

[ajk]

Did you happen to use Rahr Pilsner malt as your base grain?  It’s thought to be pre-acidified by the maltster, causing its acidity contribution to the mash to be greater than other base malts.  That could result in better attenuation than expected.

[yso191]

Am I reading between the lines correctly that the refractometer calculator in BeerSmith may be inaccurate when calculating fermented/ing wort?

[blatz]

@yso191

Am I reading between the lines correctly that the refractometer calculator in BeerSmith may be inaccurate when calculating fermented/ing wort?

once i got my correction factor adjusted through some trial/error, mine has never been off my hydrometer.  I do both on occasion and they always match within .01 gravity points.  and this has been the same through 3 hydrometers over the years.

not sure why some folks have problems.  starting to think its guys who wear glasses or something…

[denny]

@hopfenundmalz

It is a 10% solution, so 90 gr water and 10 gr sugar.

Thanks, Jeff.

[scarper11 (Pinski)]

@blatz

@yso191

Am I reading between the lines correctly that the refractometer calculator in BeerSmith may be inaccurate when calculating fermented/ing wort?

once i got my correction factor adjusted through some trial/error, mine has never been off my hydrometer.  I do both on occasion and they always match within .01 gravity points.  and this has been the same through 3 hydrometers over the years.

not sure why some folks have problems.  starting to think its guys who wear glasses or something…

What correction factor do you use?

[blatz]

@blatz

@yso191

Am I reading between the lines correctly that the refractometer calculator in BeerSmith may be inaccurate when calculating fermented/ing wort?

once i got my correction factor adjusted through some trial/error, mine has never been off my hydrometer.  I do both on occasion and they always match within .01 gravity points.  and this has been the same through 3 hydrometers over the years.

not sure why some folks have problems.  starting to think its guys who wear glasses or something…

What correction factor do you use?

will need to check at home.

[a10t2]

@denny

Got any tips on calibration and use?

Jeff pretty well covered it:

• I calibrate with water (tap or distilled, you can’t measure the difference) before every brew session.
• When I do my quarterly brewing checklist, I also calibrate against a 20°Bx sucrose solution.
• I keep the refractometer in my fermentation chamber, unless I’m fermenting a lager, in which case I keep it in the house. The closer to the calibration temperature (mine is 20°C), the better.
• If the grain bill isn’t similar to something I’ve checked before, I take both refractometer and hydrometer OG readings and record the WCF. The FG equation is cubic, so small errors in the WCF will be compounded.
• I use a small syringe to pull ~1 mL of beer, and discard it twice to “rinse” out any sanitizer before taking the sample for testing.

That’s all that comes to mind. A two-point calibration is definitely where to start.

[fejjgw (Jeff M)]

Sean, do you have a link to a good set of pro brewer level hydrometers?

Would be interesting to look at the difference between those and the cheap ones we use:)

Jeff

[el_capitan]

@ajk

Did you happen to use Rahr Pilsner malt as your base grain?  It’s thought to be pre-acidified by the maltster, causing its acidity contribution to the mash to be greater than other base malts.  That could result in better attenuation than expected.

Interesting.  I haven’t heard a lot of positive feedback on Rahr pilsner, but I use Rahr 2-row quite a bit.  For this batch I used the end of a bag of Best Malz pilsner.  Good stuff!

[a10t2]

Sean, do you have a link to a good set of pro brewer level hydrometers?

Any decent supplier will carry them as a set of three. They’re large (~16" long) for high precision, generally cover something like 0-8, 8-16, and 16-24°P, and have a thermometer and correction scale. Just an example: http://www.gwkent.com/plato-hydrometers-with-build-inthermometer.html If you have a Foxx account, theirs are about half the price.

I have one of these and it’s nice, but annoying since it’s only marked in SG. They’re more delicate than the “pro” ones and not as large: Home Brewing Supplies and Home Brewing Kits

[ynotbrusum]

Had one of these - I broke it after less than a year:

Testing & Measuring for Homebrewing and Wine Making

It was nice, but I can’t trust myself with the thin stem, so I use an el cheapo and a refractometer.