Gravity question

Hogarthe said:
I don't think the sugar is going to settle while your wort waits. Its dissolved into solution, so unless something happens to cause it to come out of solution, it should stay evenly throughout the liquid. I don't know what could cause it to come out of solution. Like a can of soda has sugar in solution and you drink it weeks after its made, the sugar is still evenly mixed in the soda. It doesn't settle leaving you with a non sweet half and a double sweet half.
Click to expand...
Agreed. The only reason it should stratify is if it weren't well mixed (which would happen over time). Sugar is so soluble it won't "settle" under normal conditions.
 
jeffpn said:
I don’t think trub/break/sediment affects gravity readings, unless there is so much of it that the hydrometer is sitting on it. Trub is just stuff in the liquid. It doesn’t contribute to the density of liquid like sugar does.
Click to expand...

My sample from the pump and hose has a lot of trub/break material suspended in it and takes a while to settle out to a degree that the hydrometer doesn't touch it. I see between 2 and 3 points difference in gravity after settling. Think of it like air bubbles in the wort with the opposite effect. Neither is in solution, but both affect the density because they share space with the solution.
 
Air bubbles would tend to make the hydrometer float by pushing it up. I could see where it could cause a false reading. What about that glitter beer? Who thinks glitter beer has a higher gravity than its non-glitter counterpart?
 
jeffpn said:
Air bubbles would tend to make the hydrometer float by pushing it up. I could see where it could cause a false reading. What about that glitter beer? Who thinks glitter beer has a higher gravity than its non-glitter counterpart?
Click to expand...
I think that would definitely affect reading until it settles out (the first two pints had all the glitter). I didn't add glitter to SWAMBO's until packaging though so I don't have any data to back it up. There's no trace of it now aside from a pink tint left by the dye in the luster dust.
 
Beer_Pirate said:
I think that would definitely affect reading until it settles out (the first two pints had all the glitter). I didn't add glitter to SWAMBO's until packaging though so I don't have any data to back it up. There's no trace of it now aside from a pink tint left by the dye in the luster dust.
Click to expand...
well as long as the glitter didnt come out of you in the TOILET:eek:! imagine that..
 
Maybe try an experiment... can you take an undisturbed sample from just above the settled trub and then take one near surface and compare the two?
 
I’ve tried using the thief to get wort from the middle of the kettle, hoping it’d be pretty clear. It takes forever for my kettle to settle!
 
We’ve talked about a snow globe before. Would the specific gravity of the water inside depend on whether the snow was suspended or settled? In my mind, since it’s not dissolved in the water, it doesn’t contribute to the density of the water.
 
Here's a nice math-y similarity from stack exchange. The scenario is a little different, since they're talking about a spherical buoy chained to the bottom of a tank, but it's some food for thought. The question itself makes the assumption that water with particulates (not in solution) has a higher density than water without.
 
Way too much for me (especially since the first equation would have to change since hydrometers aren't spherical)!
 
OK, I brewed today and, as usual, took my sample for OG by draining the pump and hoses so there was a good amount of break material in it. I took the first hydrometer reading of 1.052 right after filling the hydrometer jar at 80 degrees F. My hydrometer is calibrated at 68, so the correction is +.0022. The second reading after the break settled to below the hydrometer was 1.051 at 70. The correction is + .0003. The difference with corrections applied was .0029, or just under 3 points.
 
You must log in or register to reply here.
Copyright © 2007-2025 Brewer's Friend, Inc. - Send Feedback - Terms - RSS Feed - Do Not Sell or Share My Personal Information

Back
Top