strength of mash

shortie · Post by **shortie** » Sun Jun 25, 2006 3:33 pm

how do you know the alcohol of the brew before and after it goes throught the still?

Watershed · Post by **Watershed** » Mon Jun 26, 2006 12:39 am

Before hand by comparing the original specific gravity of the brew to the final specific gravity using a hydrometer:

http://en.wikipedia.org/wiki/Gravity_(beer" onclick="window.open(this.href);return false;" rel="nofollow)

Afterward distillation by specific gravity with a hydrometer ( generaly you can't use the same ones as designed for brewing as they don't cover the right range ) or an alcometer - which is basicaly just a hydrometer calibrated in % alcohol. Or you can weigh a known volume and work it out from the density ( which is what I used to do until I got an alcometer ).

stillkickin · Post by **stillkickin** » Thu Jun 29, 2006 7:25 am

I am wondering what would be the effect of using an alcometer on a sugar only wort pre-distillation?

Theoretically there is no sugar: only water and alcohol (and only traces of other chemicals) so shouldn't it give us a reasonably accurate, or at least ballpark figure?

That is, unless all the dead yeasties make a big difference?

stoker · Post by **stoker** » Thu Jun 29, 2006 7:51 am

funny you mention this. I've done it today.
and my alcohol meter gave +-0° so 100% water, means, a gravity of 1000 (what you would read on a hydrometer)
maybe there was sugar left or other stuff.
I distilled it, and it did contain alcohol

AfricaUnite · Post by **AfricaUnite** » Thu Jun 29, 2006 11:01 am

having a hydrometer and alcohol meter is so handy, I dont know how people live without them, the alcoholmeter was about $8 and hydrometer was $12, $20 and theres no more guessing games.

grunther777 · Post by **grunther777** » Thu Jun 29, 2006 10:33 pm

I guess there must be a different range on some hydrometers mine basically stops at .995

Watershed · Post by **Watershed** » Thu Jun 29, 2006 11:34 pm

AfricaUnite wrote:having a hydrometer and alcohol meter is so handy, I dont know how people live without them, the alcoholmeter was about $8 and hydrometer was $12, $20 and theres no more guessing games.

Well I used to take samples from each run to work, weigh 5ml of each on a microbalance and calculate the SG that way then use a look up table but it's a stupidly long way round compared to just spending a couple of quid.

I never bother with OG reading or an SG from the fermented wort - not even when I'm brewing beer. I figure I don't need to know the strength of my beer and with the still all I care about is the output strength.

The Chemist · Post by **The Chemist** » Fri Jun 30, 2006 8:11 am

For routine checks, I use a refractometer (a little pricey, but dang handy). I've check alcohol content of beer, basically a wash, by gas chromatography (ridiculously pricey, but I had it handy). Really, the only way to check the EtOH content of a wash/beer is to use the difference method, or distill a portion and use the alcohol hydrometer directly.