Aussiedistiller, Home Distilling, Moonshine, Home Brew

Hi all,
Looking for a bit of advice on troubleshooting my 5 gen combo spirit run on UJSSM. I've googled, searched the forum and used the AD Search to no avail, so apologies if this has been asked and answered somewhere else.

Problem: five generations of UJSSM combined low wines for a spirit run, end product tastes flavourless and bad. Acrid, iodine-y after taste and a hint of heads prickle on the tongue across all cuts and down into tails; however, the stripping runs smelled great (butterscotch and corn). Stole a bit of the hearts of Gen 5 and "force aged" it to get an idea of flavour profile and it was pretty good (and I'm not a bourbon drinker).

Background Info: 23L batch generations, raw sugar used instead of white, feed grade cracked corn (probably only 1-2 cracks per kernel), 7L backset used for every generation aside from first, ~3300ml low wines collected from each stripping run (200ml foreshots discarded each run) taken down to 25%, no issues with ferments - all finished dry within 7-10 days (on a beer brewers heat pad set to 25 degrees but would've dropped overnight for some gens). Third Gen only got to 1.010 but I just ran it anyway. Lowan's bakers yeast used.

Spirit run: 22L boiler charge (once low wines diluted to ~40%), another 200ml discarded for fores (just in case), dropped energy input to under half once close to product off-take and ran at a thin, broken stream for the whole run. Fores came off at 87%, hearts (when tasting off the still) at 80% and tails at roughly 45%. After leaving open to off-gas for ~15hrs, went to sample cuts in order to blend and everything tasted bitter, astringent, no flavour and a bit heads prickly.

Still: 50L keg CCVM run in pot still mode, 1 x 2000W element hooked up to a 5 Star voltage regulator, 2 inch copper column at 1200mm, 2inch shotgun condenser at 500MM.

Working theory: I've either run it too quick and smeared heads into everything, or got some passive reflux from the column and the ABV is too high to carry over any flavour congeners with the ethanol. Looking at an ethanol liquid/vapour chart, 40% shouldn't be hitting 87% without some sort of reflux.

Any help much appreciated in figuring out where I've gone wrong and whether it is salvagable or not. I'm trying my luck and running the whole thing again with the column insulated and much slower off-take.

Apologies if I missed any crucial info.

Thanks all

87-80 is high for a pot on pot my heads hearts were normally 80-75 and 70-75. 40% low wines. Normally on a pot if you run too fast on a pot abv drops. You did have your rc out and top closed?

Did you collect the run in seperated cuts jars? How much per jar?.

not sure if this is any help as i have a 2" CM, but i have a 1.2m column (1 x 600mm + 1 x 500mm) and only use one of the pieces for pot still mode.

bluc wrote:Did you collect the run in seperated cuts jars? How much per jar?.

Definitely had top capped and RC nowhere in sight. Did small cuts where I assumed the changes would be. So first 2L was in one big jar, then 300ml jars until the hearts stabilised, 1.8L jars for hearts, then back to 300ml jars once I saw ABV dropping to 60%.

Thanks for the help, Bluc. Re-running as we speak and I'm up to the hearts transition, so collecting in small jars for now to see what it tastes like with 2-3 drips/sec off take. :handgestures-thumbupleft:

howard wrote:not sure if this is any help as i have a 2" CM, but i have a 1.2m column (1 x 600mm + 1 x 500mm) and only use one of the pieces for pot still mode.

Thanks Howard. I suspect I'll be making a dedicated shorter column for pot mode in the near future. :handgestures-thumbupleft:

Update: Just getting into clear hearts now and the acrid, heads-y prickle has subsided as I would've expected. Corn flavour is present but very subtle. Will see what comes in later hearts/early tails.

I think a combo of too tall column meaning too high ABV for flavour to come over (someone will probably call me out on that over-simplification) and running it too fast and smearing heads into hearts caused my issues. Will report back once I've finished the run and blended in a few days time.

Thanks for the help, all.

Egg you can always time how long it takes to fill a 100 ml container as this will give you the take off rate.
Drip drip trickle Vs thin stream is very subjective and varies person to person where 2 litres an hour is the same for everyone :)

Some packing in your riser might contribute a small abv bump, depending on ambient temperature, but generally not anything major unless you're adding reflux.You wont notice a difference with a shorter riser (that's empty). Pointing a fan at it will do something if that's your aim.

Pot still spirit run speed is subject to the size if the boiler charge. Id suggest reasonably slow, 1.5lph is what id aim for on 20l, fores even slower.

Def start taking speed measurements, drip rates and broken stream are very subjective as the viscosity of the product will change by wash and even the shape of your output pipe will affect things. I frequently end up running too slow and making runs go for too long if i don't jump on it from the start.

Are you proofing down to taste? Water qty can make a big difference on flavour, try it at a spread between 35 & 45, the changes can be surprising.

Taking speed measurements is definitely sage advice. Will do so next time, thanks folks. I've also purchased a better temp probe to make sure I am getting accurate temp readings for conversion of ABV when not at 20 degrees.

Definitely no packing in column. I pack with stainless scrubbies and lava rock when in reflux mode and going for high ABV neutral, but leave it all out on pot runs.

Also, proofing down to 35-42 ABV when tasting. I've blown out my palate on high ABV before and it's no fun trying to taste anything after.

For posterity's sake in case anyone comes across this thread later, the hearts started tasting awful again on the much slower second run - bitter, chemical-like aftertaste - so I stopped the run and will chalk this one up as a hard lesson learnt. Just wish I knew where I went wrong so I can rectify for next time :))

Had plans on adding it to a TFFV low wines to bulk out my supply of neutral, but if the hearts were that bad I think better to just ditch it altogether.

Thanks for the responses, all.