Sedit - 26-10-2011 at 12:45
I know someone who makes there own hooch and since they are not a chemist I was given a sample to perform an assay on for him.
I want to determine water content first of all which should be relatively simple using MgSO4 in excess and measuring the weight gain after the fact.
I am also thinking of feeding SO2 into the alcohol to test and assay any Ketones or Aldehyde present.
Lucas reagent seems useless here since the majority of the contents are a primary alcohol it would render the test useless.
There is something in the brew which is very tart and makes ones mouth water. I want to determine what this is. I believe it to be a carboxylic acid
or an ester there of since addition of NaOH and evaporation followed with H2SO4 brought out the smell of something awful that has came over with all
the "bad" batches.
Can anyone suggest other useful test to run this through the gauntlet of simple test to determine the contents. He uses most of the EtOH for fuel
anyway but it seemed like a fun project to take on and there is always that small mid section of the distillate that we can't resist having a sip or
ten
.
bbartlog - 26-10-2011 at 16:35
Seems like a simply hygrometer should tell you the alcohol/water ratio. I mean, if there are really large amounts of other contaminants (fusel oil and
all that) then maybe it will not be dead on, but I don't think you will get any better accuracy using MgSO4.
Carboxylic acids are certainly possible. Don't know about qualitative tests for individual ones, but if you can measure pH and titrate you could at
least estimate the total quantity of acids present.
Sedit - 26-10-2011 at 16:56
Well the PH seems to be relatively neutral and yet I know there is enough Fusel oil to give it a foul taste and messed up feeling so I believe that
there is Esters in there and hydrolysis will need to be performed using NaOH to determine the concentration of the Fusels.
The MgSO4 is the first part of the test anyway so there is no reason to use anything else when I want further test to be anhydrous. Since I am going
to dry it before pumping in SO2 to check for ketones and aldehydes I figured I may as well determine the H2O content while I am at it.
What other test could be performed? Im pretty sure most organic acids are locked away as there esters, more then likely there ethyl esters.
mr.crow - 27-10-2011 at 10:04
How does SO2 check for ketones and aldehydes?
In my experience fermenting ethanol for scientific purposes, we used a lot of sodium bisulfite to kill the yeast. This gave the product a strong
sulfurous smell after distillation. The final ethanol still has a slight smell, though it is kind of pleasant.
Sedit - 27-10-2011 at 11:52
SO2 forms an adduct with some ketones and aldahydes. Sulfites are a just a source of SO2.
DJF90 - 28-10-2011 at 05:56
No, you need the bisulfite to form the adducts, at least to the best of my knowledge. If you have a reference for using SO2, the please share it.
If you suspect the foul taste to be down to the presence of esters, you might suggest your friend reflux over NaOH and then redistil. This should at
least remove the esters and the acyl portions of them (as carboxylate salts left in the still pot). The down side is that any flavouring agents in the
alcohol may also be affected.
The main concern I would have with moonshine is the presence of methanol in the liquor. As methanol and ethanol are both small aliphatic primary
alcohols, there is no simple way to test your friends hooch for methanol contamination...
mr.crow - 28-10-2011 at 07:16
I'm pretty sure if it is fermented properly there won't be any methanol. The stories of people going blind with bathtub moonshine probably come from
denatured alcohol being sold by assholes.
I like the idea of using NaOH
I tried leaving NaOH in a jug of drugstore rubbing denatured ethanol for a week to get rid of all the weird crap in it. Diethyl phthalate, who would
want to put that on their skin??? Camphor too, didn't really get rid of that smell. I was hoping for Aldol reactions on the ketone. I don't really
want to use this ethanol for a solvent because of that.
Sedit - 28-10-2011 at 13:45
I believe the reference for the SO2 adduct was on this forum and my attempts to locate it have failed so far.
Pectin is the source of MeOH in fermentation and sadly I can not rule this out as a contaminate because he makes it from such a variety of sources
some are bound to contain Pectin.
The NaOH reflux is already on the list of things to do because I have released some foul smells in the past from it but he is unable to do so because
the pot of his still is Aluminum and it will not take strong bases.
Its really strange because I have sampled it a variety of times and EVERY time even after small amounts I am greeted with a night of very vivid
dreams.... This is starting to interest me more then anything else about this alcohol.... Dreams are what started me getting interested in chemistry
in the first place because I feel if there is a substance that prevented the hippocampus from deleting them upon completion one would be able to live
the equivalent of a much longer life in terms of mental leg work.
unsub - 7-11-2011 at 03:06
I found this a very interesting thread so far. One of the very first chemistry experiments I did on my own was fermenting and distilling some alcohol.
I had noidea about methanol at the time but thee is no question what I got out of my plug in kettle ,garden hose and duct tape contraption was a mix
of ethanol and methanol. Even as young and dumb as I was at the time I knew I didn't want to drink any and ended up using it to clean my bathroom. It
worked really well for that. I "still" want to make a useful solvent and if I could get a usable fuel and a drinkable booze I would be thrilled.
I remember reading somewhere about a tribe of american indians who consider the lives they live while their dreaming just as important and real as
their waking life. That stuck with me. I would guess that you could start to exert a bit of control over your auto delete in your hippocampus by
keeping a dream journal ,meditation and being aware of it happening when you wake.
The guy who invented the wankel rotary engine used in the mazda RX7 and the new RX8 woke up from a dream with the engine fully designed. It is
complety different from conventional engines with no pistons or valve train. Mazda really deserves respect for having a product mass produced so
unlike everything else.
ScienceSquirrel - 8-11-2011 at 04:05
The best way to make your own hooch for drinking is to use a mash of malted barley with up to 30% raw grain eg flaked maize or barley. The raw grain
is optional but makes the malt go further and thus reduces your cost.
Collect your sweet wort and give it a good boil, all this is well documented on home brew beer sites.
Crash cool and then run off the wort through a bed of oat hulls or similar to remove the precipitated protein. Ferment out the wort with a good spirit
yeast that will give you a high attenuation eg maximum conversion of sugars to alcohol. Normal beer yeasts will give around 70 - 80% attenuation as
some residual sweetness in the beer is nice but for spirits this is unneeded.
Distill and pass through charcoal, this will give you a vodka like spirit.
ABV ( alcohol by volume ) can be assayed with a spirit hydrometer.
http://www.the-home-brew-shop.co.uk/cgi-bin/sh000001.pl?REFP...