RUMBLORRRR the unfermentable stuck wash

[nuddy]

Gday AD's

I've got a bad case of unfermentable rum wash.

The wash in question is now 11 days old and has barely drop a single SG point.

I've tried an vast array of techniques and experiments to get the damm thing chugging along, all to no avail. Let me run you through this character building 11 days.

15/7/18: The1st generation of a wild yeast rum experiment had just finished fermenting and been put through the still so naturally I got stuck into creating the wash for the 2nd gen.

In a 60L fermenting vessel the following was added:
9kg of bundy refinery molasses (ferm sugars of 5kg) was added with
2kg raw sugar
Onto this 6.5L of hot dunder from the 1st generation was added and mixed thoroughly with a stainless steel mash paddle.
4g DAP and 4.1g Fermaid A added along with hot and cold tap water to get it to 34L mark. I don't remember the temperature at this point but I think it was around the 35 C-40 C range.
8L of cold tap water mixed with the yeast trub/bed from gen 1 was then added and mixed thoroughly.

Starting figures for start ya bastard rum.
Temp corrected S.G: 1.100
temp: 30.0 C
pH 5.6

This was temp controlled to 30.0 C by an aquarium heater running off an ink bird controller with the temp probe strapped to the outside of the fermenter buried under a sacrificed stubbie holder to insulate it. 2 layers of towels were wrapped around fermenter to insulate.

16/7/18 - 24hrs later no airlock activity, opened lid no visible signs of fermenting taking hold, pH 4.5, 3 heaped tsp of calcium carbonate added to bump pH back up.
50ml of gen 1 wild yeast slurry warmed slowly in a bain marie style bath of warm water to 28.6 C then pitched into fermenter.

17/7/18 - 24hrs laters, ferm temp 29.2 C, veryyy slow airlock activity 1 bubble every 1-2 mins,

18/7/18- 24hrs laters measurements taken, temp corrected S.G 1.098, temp 26.7 C, pH 4.1
2L was drawn off fermenter and diluted to 3.27L in a 5L demijohn for a S.G of 1.060 to see if lowering S.G would relieve osmotic pressure of yeast and fire up fermentation.

21/7/18- 72hrs later, 80g of dried bakers yeast pitched into now 40L of rum wash.
3.27L lower S.G experiment was heated slowly over stove, had 8g of bakers yeast hydrated and pitched into it along with 2 tsp of calcium carbonate, pH was raised to 4.4, temp 33.0C, SG 1.059

22/7/18- 24hrs later, 40L wash measurements taken, pH 4.1, S.G 1.090, temp 22.0C, 7 tsp calcium carbonate added, then whole wash was diluted with 8.2L filtered tap water to S.G of 1.076, temp 26.0 C, additional bakers yeast pitched onto surface of wash.
3.27L experiment slowly chugging away.

24/7/18- 48hrs later, now 48.2L rum wash now, pH 4.0, temp 28.0C at bottom of wash, 32.0C at surface of wash, S.G 1.070.
3.27L experiment, pH 4.3, temp 18.0C, S.G 1.030, finalllllly somethings fermenting. I then dumped this 3.27L of actively fermenting wash back into the 48.2L of non fermenting rum wash to try get it kicking over.

25/7/18 - 24hrs later, no ferment taken hold, 20g bakers yeast hydrated in warm water with 3 tsp sugar for 25mins, bakers yeast went nuts and was added to approx 52L unfermenting rum wash.

26/7/18 - 24hrs later, S.G 1.070, not moved a single S.G.

I'm at a loss as to why this dammmm wash wont ferment out.

It's got 24hrs before I dump it. Anyone got any ideas on whats going on?

[coffe addict]

The only times I've had rum wash issues I've changed molasses supplier's and the issue went away.
That said I've no idea what molasses I get as it's always stock feed.
Good luck

Edit: your sg isn't the issue as I've had sg of 1.30 finish with out problems back when I bothered to check

[nuddy]

Yeah its got me boggled. Bundy refinery molasses has never steered me wrong.

My brewer roommate has offer a suggestion that since I use tap water unfiltered I may have filled during a chlorine/chloramine spike on the municipal system.

Who knows, this lots going to the drain.

[woodduck]

I'd love to be able to help but I've got no idea sorry.

This probably won't make you feel better but I had a 200ltr bwko fermenting in the shed with some plastic wrap on it. I went in there the other day and obviously something had jumped on top of it, torn through the plastic and had a bit of a swim around, I'm looking squarely at the pet goat! It looked all funky and pussy and I thought well that will be going out. Went in there today (a week later, yes I'm a lasy bastard) to get rid of it and the bloody thing is bubbling away with a nice crust on it, still no plastic cover :laughing-rolling: so I threw a lid on it and I'll call it goats juice :laughing-rolling: it's funny how ferments can be so unpredictable. I could lend you the goat if you like? :teasing-tease: :laughing-rolling: :laughing-rolling:

[Nathan02]

roasted goat leg sounds better then stinky billy juice woody :text-lol:

[Doubleuj]

roasted goat leg sounds better then stinky billy juice woody :text-lol:

:laughing-rolling:

[woodduck]

Ohh it's on the cards, it's a prick of a thing. It jumps and craps on everything. I can't keep the bastard in the paddock.

[EziTasting]

Ohh it's on the cards, it's a prick of a thing. It jumps and craps on everything. I can't keep the bastard in the paddock.

Just take a leg at a time... that’ll fill the dinner table and slow that sucker down!!! :laughing-rolling:

[scythe]

Sounds like something else took over the wash this time instead of yeast.
pH is dropping so something is working in there.

Chlorine might have killed the initial yeast which allowed what ever is in there now to breed.

[nuddy]

woodduck I've left the lid off to see let mischief mother nature have a go, might be time to let loose the goat.

[woodduck]

Have ya got a dog? Or a small child even? :laughing-rolling: :laughing-rolling:

[Yurugaboy]

Have ya got a dog? Or a small child even? :laughing-rolling: :laughing-rolling:

:laughing-rolling: :laughing-rolling: :laughing-rolling: :laughing-rolling:

[hillzabilly]

Does ya wash taste sweet still or more bitter like a finished rum wash,I like ta regulary taste wash too help keep an eye on things ,have been surprised at the difference in molasses quality at times,have also used 100% soft dark brown sugar from CSR for rum with very good consistent results with excellent flavour,airating a wash prior to yeast pitching will help it get going quicker as well.cheers hillzabilly :handgestures-thumbupleft:

[YarraRanges]

That's very strange, molasses has just about everything a little yeasty needs.
I always us blackstrap molasses from the feed store and white sugar. Some molasses has sulphur added which can kill yeast.
If using mains water let it off-gas the chlorine for about 5 hours before you use it.
If you aerate the wash properly and then pitch the yeast at around 30C, the yeast multiplies while using up the extra oxygen in the wash. If it's done properly your yeast will triple. Once the oxygen is gone it then goes into ethanol producing mode. The ferment should look like a fast rolling boil that will finish in 4 to 5 days.
If you add some DAP you'll need to put vegetable oil on top to reduce the foaming.
10g of epsom salts and a small fingernail of butter (yeast need cholesterol to build it's cell walls) will also help.

[EziTasting]

Unable to add anything to the quality of your molasses (have a 44Gal drum just sitting there not wanting to ferment), but virtually all of my stuck ferments have been due to a pH that’s too low!
Bluc pointed out that I need to be aiming at 4.8-5.4 pH... so when I get my washes in that vicinity, they bubble away nicely!

How’s this wash going?

[fizzix]

I always throw in a brew bag full of a handful of oyster shells into washes and mashes.
They use them for poultry feed supplement, so are easy to get here in the states.
Shells of any kind make an efficient pH buffer, and leaves one fewer thing to worry about.

[EziTasting]

Agreed.

I’ve taken to using ‘shell Grit’ for on the stock feeders...

[nuddy]

I'll give you all the quick version here........... it went down the drain.

It still tasted quite sweet, hillzbilly.

I left the lid off hoping to see if something floating around in the shed would set up shop and go nuts (room mate brews beers so plenty of potential floating around in the air). Alas after a week and a bit nothing had taken up residence.

I umm'd and ahhh about what to do with it. In the end I sent it down the drain. :handgestures-thumbdown:

You live and you learn.


On a different but similar note, I've another 50L rum wash using feedstore blackstrap molasses that's just ticked passed using 1/3 of it potential attentuation with a pH drop of 5.5 to 4.3 in just under 20 hours. Went back to basics with this one.

[danwbrews]

Not knowing the temp difference between the yeast starter and the wash is where I see the problem. If there is a more than 8 degree F in temperature between the two, the yeast go into shock. You should always temper your yeast to the temp of your wash. Its a slow process but is doable. You add a small amount of your wash to the starter, say 1/4. let it set for a while (see a fermentation start). Then add 1/2 the amount to the total of the first addition. Let that set a while then add the yeast the main wash. Yeast go into shock if there is to much difference in temp. This will cause them to stop growing or even killing a vast amount of them. Least case you will get lots of esters that will not produce alcohol but lots of tails (too few yeast cells). Worst case you will get an infection (slow ferment start that allows souring stuff like Lacto to take over) . Any way your yeast and wash should be at the same, or within 8 F, temperature when pitching for a clean wash. Poor quality yeast will always cause a stuck ferment. Being a beer and wine brewer for over 25 years I've seen it all (stupid mistakes by myself) and also from people I instruct in those passions. Yeasts are your friends. Treat them well and they will reward you with a good product, mistreat them and they will mess up your final product.
Sorry for the rant, been teaching this a while.


Dan

[nuddy]

Not knowing the temp difference between the yeast starter and the wash is where I see the problem. If there is a more than 8 degree F in temperature between the two, the yeast go into shock. You should always temper your yeast to the temp of your wash. Its a slow process but is doable. You add a small amount of your wash to the starter, say 1/4. let it set for a while (see a fermentation start). Then add 1/2 the amount to the total of the first addition. Let that set a while then add the yeast the main wash. Yeast go into shock if there is to much difference in temp. This will cause them to stop growing or even killing a vast amount of them. Least case you will get lots of esters that will not produce alcohol but lots of tails (too few yeast cells). Worst case you will get an infection (slow ferment start that allows souring stuff like Lacto to take over) . Any way your yeast and wash should be at the same, or within 8 F, temperature when pitching for a clean wash. Poor quality yeast will always cause a stuck ferment. Being a beer and wine brewer for over 25 years I've seen it all (stupid mistakes by myself) and also from people I instruct in those passions. Yeasts are your friends. Treat them well and they will reward you with a good product, mistreat them and they will mess up your final product.
Sorry for the rant, been teaching this a while.
Dan

Danwbrews no need to apologies for the rant, some interesting and good information you've provided there which backs up some reading I did. Always a nice thing to find out :handgestures-thumbupleft: A few months after this kerfuffle I stumbled across yeast pitching temperature differences and the addition of wash to slowly bring it within temperature tolerances. The book I was reading called it "attemperation", it's something I am much more aware of now a days, I unfortunately do not remember the temps when trying to get that rum wash to start.

Yeast go into shock if there is to much difference in temp. This will cause them to stop growing or even killing a vast amount of them. Least case you will get lots of esters that will not produce alcohol but lots of tails (too few yeast cells).
Dan

I don't suppose you have any more information on this increase in the production of esters that creates lots of tails? Is that not the reason people underpitch yeast and ferment hot to create a slightly stressful environment for the yeast which then create these flavourful esters as a response? Or it is producing the wrong esters?