hydrometer sampling

[Hex]

I know I could just go out and test this question on my latest batch that I'm getting ready to bottle, but:

Does it matter from what position (top, middle, bottom) a sample is drawn from the settled and still beer in a glass carboy for an accurate final gravity reading?

 

[mikebiewer]

I'm going to say no, only because I've never heard that it does.

 

[soxpats]

i generally stick the theif down towards the middle of all the beer to take a sample...i doubt that it actually matters very much, if at all, but it works for me!

 

[Hex]

I've been surfing and found some interesting articles on miscibility solubility and homogeneous solutions, but still no definitive answer. In my mind, the alcohol and water in beer are completely homogeneous in solution, unaffected by gravity and time in a carboy, but sugars are not. It leads me to believe that a gravity reading taken from the bottom of a carboy will be grater that one taken at the top. Any thoughts?

http://www.800mainstreet.com/9/0009-002-process.html

http://www.800mainstreet.com/9/0009-001-mix-solut.html

 

[Frank99]

Why don't you take a sample from the top/middle/bottom and see if the readings are the same. Sounds like a good experiment!

 

[LVBen]

I know I could just go out and test this question on my latest batch that I'm getting ready to bottle, but:

Does it matter from what position (top, middle, bottom) a sample is drawn from the settled and still beer in a glass carboy for an accurate final gravity reading?

I doubt it matters... you ever heard of a beer label that says to stir before drinking?

 

[david_42]

It might if you left the beer for several years in perfect thermal isolation.

 

[Justibone]

I doubt that the hydrometers we commonly use are precise enough to reliably measure the difference. True sugars should diffuse relatively equally throughout a aqueous solution, however differential sucrose densities can actually be used as a density column in a centrifuge, so... hmm. It would have to be experimentally settled. Someone wanna call Mythbusters?

TLDR; it shouldn't matter.