Aussiedistiller, Home Distilling, Moonshine, Home Brew

So I have found with a big ferment 200l that the longer the wash sits the more it seperates in the fermenter with the alcohol going to the top.(I have done runs where the third/last run yields as much as first two combined)
So my question what is the best way to get reliable reading using a hydrometer on the ferment in this situation.. :think:

first thought just use a wine thief to check the depth of the ferment

I do 200 litre rum washes and I haven't noticed any difference between the first strip run and the last. How long you been leaving them sit and what wash was it?

Sugarhead whiskey usually 3 weeks sometimes 4

well, alcohol is lower density than water. it would make sense. but I cant say ive taken that much notice on my stripping runs. i tend to strip stright into a 50L keg these days

orcy wrote:well, alcohol is lower density than water. it would make sense. but I cant say ive taken that much notice on my stripping runs. i tend to strip stright into a 50L keg these days

:text-+1:

I haven’t had this happen, but haven’t done many large ferments. Thinking though, once it’s alcohol it’s alcohol. Otherwise you’d leave your fermenter for a while and siphon off the top third instead of distilling, no?? If you leave a beer in the fridge for a while, the alcohol doesn’t concentrate at the top.

Are there any other factors bluc? Heater at top of FV not heating bottom? FV sitting on cold concrete?

Next time maybe check gravity before drawing off your boiler charge then check gravity remaining in fermenter.

:text-+1: check gravity of each boiler charge, I've not noticed a difference in yield between first and last/third run from a 200L drum.
So if it's happening it must be a relatively small difference in alcohol content.
If you're worried about it rack the lot into a secondary fermenter and stir prior to filling your boiler

No factors dig, no heaters etc. It aint a big deal but I am getting different reading with hydrometer from scooping off the top to using bottom drain. I have done heaps washs, but am trying to learn to use the tools of the trade reliably..

bluc wrote:No factors dig, no heaters etc. It aint a big deal but I am getting different reading with hydrometer from scooping off the top to using bottom drain. I have done heaps washs, but am trying to learn to use the tools of the trade reliably..

I found going the hydrometers just weren't accurate enough for our 2000 litre washes. We went to a brix meter to give us accurate readings of our ferments.

Hanna Instruments HI96813

They are quite expensive :scared-eek:

Looks cool but bit ott for my needs. I will just continue with my routine. Getting the right volume just wanted more accurcy for working out potential abv for my own notes. All good cheers.

It is lower density than water but the law of diffusion should negate it from doing this. If it is separating I'm not sure how as both water and alcohol are polar so should mix well.
:-B

Edit: Is it possible you're reading at a different temperature near the bottom than at the top throwing out your measurement?

Warra any other explanation for higher gravity out the bottom tap then off the top?

Could be the solids and unfermentable stuff dropping after fermentation has finished. So the bottom of the wash is thicker than the top.

I know its not solids I even once ran some wash through a coffee filter and got the same gravity reading as before I filtered. Being a sugar wash I never thought of unfermentables. I quite often get a difference in gravity of 1.02 at bottom and 1.000 at top.
My sugarhead whiskey i get 3 keg charges. And often get as much volume out of the 3rd run as first two combined. Not always though if I run it straight away after it finishs fermenting. I get roughly equal amounts. I just find it weird but seperation was the only thing I could think of..

bluc wrote:Warra any other explanation for higher gravity out the bottom tap then off the top?

Not that I can think of. The pressure difference would be negligible, temp might be different and also as mentioned may be more solids thickening it up near the bottom. Maybe some indigestible heavier sugars sink to the bottom which may not filter out with the solids but increases the concentration near the bottom displacing the ethanol to the top to maintain the diffusion ratio?
This is just guessing. Without some sort of testing its all just a theory.

Sounds like a reasonable assumption also cheers :handgestures-thumbupleft: