Brix hydrometer help

[DonutBrew]

Hey guys,
I brewed a lager with a friend in another city about 3 1/2 weeks ago, I brought all my equipment, he supplied the stove, carboys, and basement for cool fermenting temps. We measured the OG with my hydrometer (1.040) and expected to get to under 1.010. Now, the problem is all he's got to measure the FG with is some wine-making hydrometer that only has a Brix scale. It's not a refractometer, but a smaller hydrometer-shaped tool. It measures water at 0 and the fermented wort at ~5. Assuming him to have a regular hydrometer, I did not take a Brix reading of the OG.

It is a pilsner (100% German Pils, double decoction) and it is fermenting using WY2278 (Czech Pilsner). The basement has been around 47-50 deg the last couple of weeks, which is at the very low end of the fermentation temp for 2278.

He says there were some bubbles on top, the beer was pretty clear, and that he didn't notice bubbling in the air lock.

Questions then are (1) Is there any way to reliably convert his 5 Brix reading to SG? and (2) is this beeyotch finished? And I suppose (2b) if it's not, should I just wait it out or do something to make it keep going?

Thank you for any help or advice!

(Cross-posted in fermentation--perhaps not the right place)

 

[nealf]

Beersmith is saying it converts to 1.007 according to my computer.

 

[DonutBrew]

Cool, that's what I was guessing based on a couple of web calculators I was using. Two more questions...

1. Does any one know of a thing that is not a refractometer and looks like a small hydrometer that measures Brix?

2. Is there any good way to think about what Brix means? That is, I can wrap my head around the fact that SG 1.020 tastes sort of sweet, there are sugars, and 1.005 tastes really dry, less sugar. When I was trying to think about Brix, the table at http://www.fermsoft.com/gravbrix.php gives a conversion ( I suppose for OG ) of Brix to SG and estimates that 5 Brix = 1.020 SG. However, when I use a calculator like that on BeerSmith or at http://onebeer.net/refractometer.shtml and tell it that I had a beer that went from ~10 Brix to about 5 Brix, it says the final gravity should be around 1.007 (as noted in the above post). What exactly is it measuring and why does the change in Brix not vary directly with the change in SG? Does this short-hydrometer-like-thingie measure in Brix equivalent to what you would get with a refractometer?

Thanks for putting up with all my questions.

 

[nealf]

1) I have no idea, probably just some old school wine equipment.

2) Brix is simply the percentage of sugar in solution. 10 Brix (~1.040) means 10% of the solution is made up of sugar. Brix apparently gets mixed up when alcohol is in the mix and therefore has to be adjusted.

btw, welcome, what part of GA are you from?

 

[DonutBrew]

1) I have no idea, probably just some old school wine equipment.

It is most definitely old. I glanced at it before I went home, figured he knew more about it than me.

2) Brix is simply the percentage of sugar in solution. 10 Brix (~1.040) means 10% of the solution is made up of sugar. Brix apparently gets mixed up when alcohol is in the mix and therefore has to be adjusted.

Percentage sugar makes plenty of sense. Thanks.

btw, welcome, what part of GA are you from?

Thanks! I'm in Atlanta, not too far east of Midtown.

 

[eriktlupus]

2...brix is what most refractometers measure sugar in and nealf is right in that alcohol changes the formula for conversion. this means that conversion calculators need starting and current brix readings to accurately convert to SG.