wort stratification vs beer stratification

ok this is bugging me. If I have to worry about my SG and OG stratifying. then how come not when pulling a sample off the top of my carboy for FG?

I assume you're talking about the stratification you get if you top off your wort with cold water? That will mix out on its own too, it just takes some time. When you pull a FG reading, it has already had ample time to distribute out.

Because the fermentation process mixes the wort very completely and once fermented, the beer does not stratify.

Because when you add water to beer you have 2 materials with different SGs. As the yeast turn the combination to beer the differences even out. You get a line separating water and oil. You do not get a line separating water and water.

ok so i thought in the mash and brew kettle it was just different concentrations of sugar water vs water. sugar being heavier. and in the carboy it is sugar water ( unfermentable) vs water vs alchohol. with alcohol being the lightest.

and i also figure the longer it sets the more it statifies

carrolte said:

ok so i thought in the mash and brew kettle it was just different concentrations of sugar water vs water. sugar being heavier. and in the carboy it is sugar water ( unfermentable) vs water vs alchohol. with alcohol being the lightest.

Click to expand...

Nope. Dissolved sugar will keep equal concentrations throughout the water.

one less thing to worry about i guess. thank you.

MalFet said:

Nope. Dissolved sugar will keep equal concentrations throughout the water.

Click to expand...

I'm going to have to disagree. I've long ago found that wort will quickly stratify. For instance, when I whirlpool, I have to retrieve my refractometer sample immediately after the mixing or the surface layer will have a lower gravity. This occurs in minutes. Test it for yourself. After boiling, perform your whirlpool and immediately collect and test a sample from within an inch of the wort surface. Then collect a sample after 15 minutes from a similar near surface location. It will have a lower gravity.

mabrungard said:

I'm going to have to disagree. I've long ago found that wort will quickly stratify. For instance, when I whirlpool, I have to retrieve my refractometer sample immediately after the mixing or the surface layer will have a lower gravity. This occurs in minutes. Test it for yourself. After boiling, perform your whirlpool and immediately collect and test a sample from within an inch of the wort surface. Then collect a sample after 15 minutes from a similar near surface location. It will have a lower gravity.

Click to expand...

I can do you one better. I've got a better bottle full of beer that's been aging for three months. I just took a sample from the top and another from the bottom with the racking arm, and the densities are as close to identical as I can measure. *shrug*

I guess I didn't state it plainly enough. This stratification does occur in WORT. i agree that it does not occur in beer.

mabrungard said:

I guess I didn't state it plainly enough. This stratification does occur in WORT. i agree that it does not occur in beer.

Click to expand...

Hmm...You've got me curious, but I'm still not sure I buy it. Why would wort behave so differently than beer? In both cases, the question is whether or not the sugars in solution stratify at different depths.

I just opened up a pint jar of canned wort. Tested the bottom, tested the top, shook it up and tested the middle, waited an hour and tested the top again. All gave me identical numbers.

In any case, the question asked by the OP was about stratification at FG, and that's what I was speaking to.

@MalFet
Thank you for your experiment. That basically helps me with my predicament. Whether or not I can trust the FG reading from the top of my carboy, with my barley wine that's been in primary for three weeks now.

@mabrungard
I too had similar results as you with my post boil wort. Which is what raised my concern. I will admit I do not have enough experience to rule out user error, but I plan on keeping an eye on this apparent tendency to stratify the OG.

Obviously somehow beer in a keg seems to stay well mixed. otherwise that last draw would be pretty damn strong. Maybe it just has to do with high concentrations of sugar and the tendency for it to want to concentrate and fall to the bottom. Creating big differences from the top and bottom. But after fermentation there is a lot less sugar and therefor much less noticeable differences in gravity.

carrolte: are you topping off your wort with water?

MalFet said:

carrolte: are you topping off your wort with water?

Click to expand...

no, full boil ten gal batches.