gravity sampling

[techrunner]

how much would it impact the gravity if i sample from about 1" above the trub as compared to sampling off the top? i just sampled off the racking port on my better bottle, and i got 1.020, just curious if i got much of the trub or anything in there that would cause it to read higher than it actually is. anyone have any data on how much variation there is from the top versus the bottom sampling?

 

[david_42]

The variation is minor to non-existent. The fermentation process keeps the wort/beer mixed and any trub in the tube will settle to the bottom. The main problem after the fermentation starts is small bubbles of CO2 collecting on the hydrometer.

 

[MilwaukeeBrewGuy]

good question. How would that same sample taste compared to one taken off the top. The reason i ask is i am never fully pleased with the way they taste, but maybe i am expecting too much.

 

[whatisitgoodfor]

Almost identical, unless you slurped up some yeast as well.

For fun, you should look really closely at your better bottle during high krausen (if it's a darker beer you'll have to shine a flashlight to see well enough)

The roller coaster ride that the yeast are taking is actually pretty damned entertaining to watch and impressive, considering that there's no external agitation. They also churn the beer up enough while it's fermenting that you can assume that there's no difference between the top and bottom.

 

[techrunner]

well, i have left it in there two weeks, so i think that the yeast are about done mixing it up for me. i did move the hydrometer around a bit, and make sure that it was a flat sample. just that my calculations were at like 58% apparent attenuation, which seems really low for a white labs irish ale yeast. i have a fermometer ordered, but i'm not sure that i didn't let the yeast get a little too cool. i moved it into a little warmer room now and swirled gently to get them moving again though.

 

[whatisitgoodfor]

How cold did it get?

If you made it down into the 40s it's possible that your yeast has flocculated and is now on the bottom of the fermenter.

 

[techrunner]

i'd guess 55 or so at coldest room temp. maybe not even that cold. i should check the spot it was in, but i really doubt it even got to 50. i guess it will have another week or two to sit anyway, so i'll just leave it. i could bottle on the 4th, that'd be right at 3 weeks in the primary. i was gonna leave it a month, but the first batch is running low, so i need a replacement. and my next kit is en route, so i was just gonna pitch that one right onto the cake.