Stripping and Puking

[doctee]

I stripped my 5th all grain cornmeal wash yesterday. I strain it first through a nylon bag, but a significant amount of solids still makes it through. Things were going nicely at first, then decided to turn the heat up a bit on my propane fired 2" x 48" Bokakob LM design running as a pot still. I was shooting for around 3kW of power measured at the condenser. Suddenly raw wash started coming over in a very fast stream. Got control of it, but it happened again after loosing my focus a little later. DAMN! I don't think it is ruined cause I can clean it up in the spirit run, correct? Frustrating nevertheless. After the run I did a post-op analysis and read some topics on this forum I came up with these suggestions for future strips.

1) I over filled the boiler. My boiler is a 10 gal milk can. I had been filling it to just at 9 gal right where it starts to neck and most of the time if being real attentive to flame and the power level I can get away with running at around 3 kW. This time I had about 9.25 gal and it was just up into the neck, not good.

2) Power level. Things were pretty smooth at around 2.5 kW, but I wanted to speed it up a bit. I was making very small increases to the flame, but when I gave it a big bump, that is when I got into trouble. So for now, limit strips to 2.5 kW until I figure things out, and remember make very small increases in power.

3) Next time it pukes. Immediately shut the off take valve after lowering the flame to limit the amount of damage. Don't sit there and watch in amazement hoping it will get better, it won't.

4) Add boiling stones and defoamer. I have always added about a tablespoon of manteca as a de-foamer for washes with lots of protein in them, but have never used boiling stones. Posts on this forum say to put enough things in the boiler to cover the bottom. A combination of copper couplings and ceramic rashig rings is where I am headed next time.

I do 2 strips and a spirit run, so if I get it right on the 2nd strip, hopefully that will "water down" the damage already done.

Persevering and charging forward,

Todd K.

[Coaster]

@ toddk63,

Rule of thumb boiler charge should not exceed 75% of the boiler capacity. In short don’t put more than 7.5 gallons in your 10-gallon boiler.

Also suggest that after your mash has fully fermented that you carefully rack your mash from your primary fermentor to a secondary fermentor. This allows the mash to thoroughly clear in the secondary fermentor and allows the mash to be removed from the lees (spent dormant yeast) sitting on the bottom of the primary fermentor. Allowing the fermented mash to sit on lees can cause undesirable smell and/or flavor in the finished sprit product. Racking from the primary fermentor to a secondary fermentor and allowing the mash to settle until clear ensures that your mash is clear and you don’t have to be attempting to filter particulate matter from your mash.

Regards,
Coaster

[Bull Rider]

Ya haven't really ran a potstill until you puke it a few times. Back off on the boiler charge, and back off on the heat.

Too much heat at the start is the quickest way to puke the still, later in the run, it can take more heat.

I've used defoamer (Fermcaps) for beer, works like magic, it should work with a still too.

You're learning the very best way, hands on!

Bull.

[rad14701]

Did you pull out all of the packing...??? Are you sure it's puking and not just flooding due to the excessive amount of vapor combined with an inability for the condensed spirits to fit through the needle valve...??? I completely remove my needle valve for stripping runs for this very reason... I can't do an aggressive stripping run with it in place...

[Prairiepiss]

You should watch your alcohol intake. Pukeing is alcohol abuse. And we don't need you stripping either.

[doctee]

It was definitely puking. It was raw beer that came over. There is a 1/2" layer of cornmeal silt on the bottom of my carboy of 2 1/2 gallons of yellow tinted cloudy low wines. All packing was removed except I keep one at the top of the column to help catch minor burps.

I am seriously considering reducing boiler charge volume to 80% (8 gal) from 90% (9 gal), but at the same time wondering if the boiler chips will allow me to get away with 9 gal with a bit more safety margin than I had. I like to run things at their maximum capacity.

[rad14701]

It was definitely puking. It was raw beer that came over. There is a 1/2" layer of cornmeal silt on the bottom of my carboy of 2 1/2 gallons of yellow tinted cloudy low wines. All packing was removed except I keep one at the top of the column to help catch minor burps.

How did the "silt" get into the boiler...??? It should have been left behind in the carboy...

[doctee]

Yes it probably should have been racked off. I got lazy , I guess.

[rad14701]

Yes it probably should have been racked off. I got lazy , I guess.

Consider it one of lifes many learning experiences...

[Bull Rider]

Boiler chips won't make a significant difference, as I said before, back off on the charge, and back off on the heat. Once you get used to your system and mashes, then you can try a little larger charges.


Bull.

[doctee]

I stripped the second of two washes for this cornmeal whiskey project today. The stillin' gods were shining down on me. It went flawless and I even pushed the envelope quite a bit.

From my opening post on this thread we all believed that the puking was due to overfilling the boiler, solids in the boiler (cornmeal), and / or too much heat.

I initially racked the first of the two 4.5 gallon buckets of wash. But getting only 3 gal of clear wash and 1 1/2 gal of cornmeal sludge, I bravely decided to throw it all in not wanting to accept the 3 gal loss I would have had from both buckets. I used a healthy amount of manteca (2 TBS) as a defoamer. I usually use 1 TBS. I also used 68 boiling chips made from 3/8" dia copper tubing cut about 1/2" long. I have to also add that I used my new Bokakob Single Reducer LM head with a 1" throat instead of my old 3/4" throat head, but I don't think that made any difference here. I filled the 10 gal milk can boiler to 9.0 gal. Right where it starts to neck in (once again feeling brave). When it first started running off, I was only running it with 1.8kW. I slowly pushed it up to 3.0 kW over 25 minutes and held it there for the remainder of the run. Total run time from first drip to burner off at 210.6°F vapor temp was 1 hour 25 minutes...and clear as crystal!

Todd K.

[Prairiepiss]

Now since you threw the whole ferment in. Did it scorch on the bottom of the boiler? All those solids can easily scorch and ruin a good run. Just sayin. There is a reason most of us rack off the lees. And accept that loss. Which isn't that much in the grand scheme of things.

[Samohon]

Done it myself...

Trying to get a good charge going in the boiler, funny thing is, when I filled the boiler, I knew there was too much in it...
I Dont do it now though, 30L max in a 50L boiler.. No puking/flooding on my stripping runs...

As Rad said, definitely a learning experience....

[doctee]

Now since you threw the whole ferment in. Did it scorch on the bottom of the boiler? All those solids can easily scorch and ruin a good run. Just sayin. There is a reason most of us rack off the lees. And accept that loss. Which isn't that much in the grand scheme of things.

Now too clarify, I remove most of the solids by straining thru a nylon bag. I start with 12 gal of mash into the fermenter. After straining, I have about 9 gal to the still. A considerable amount of finer particles still gets by though. I had done it this way 4 times without a problem and only the 5th time did it puke. I was probably always on the ragged edge of puking those first 4 times as well. Adding the extra measures (no more than 9 gal, more manteca, boiling chips, slowly increasing heat) seems to have given me that safety margin I was looking for.

I never had a problem with scorching. I could see where that might be a problem with an electric element, but I am propane fired.