Brix and High ABV sugar washes and alternate still heating

[nb0s]

Hi I am a newbie at this game. To date I have only completed 2 Turbo washes. Currently underway I have a TPW and a DWWG. I have been lurking around the Forums reading many interesting articles and posts. I really would appreciate any and all help.
I have a few questions the first are from an excellent article on High ABV Sugar Washes on www.homedistiller.org a site commonly referenced from this forum.
!). I note that the wash should remain aerobic for the first 48 hours and that the yeast should remain in suspension for the entirety of fermentation. To this end I thought a small submersible pump could assist. Has anyone tried this and if so what sort of pump did they use. My thought was to use a pump from the aquarium world.
2). I need some confirmation or correction of my perception of brix. As I understand it an initial SG of 1000 means zero sugar zero ethanol and zero brix (ie pure water). Whilst an initial SG of 1040 for a sugar wash prior to yeast addition represents a wash very near a brix of 10. Therefore to keep the brix sub 20 the initial wash should remain below SG 1080. Now as the wash ferments and ethanol is produced the SG falls. At about SG 1000 the mash should contain approximately 10.5% ABV. A pure water ethanol mix of 10.5% should produce a SG of slightly less than 980. Therefore the mash at SG 1000 should have a brix of 5. Now the article refers to maintaining the brix between 4 and 6 brix so when the SG drops to 996 some sugar could be added to bring the wash to 6 brix. Overall the remaining sugar to create the additional rise in ABV of 5% should be added in 2 brix increments or an SG increase of 8 keeping in mind the fact, that as one approaches 15% ABV a pure water ethanol mix would have an approximate SG of 970 and the SG of a 4 brix wash will drop to 986.
In summation, one starts by adding sufficient sugar to bring the sugar water mash to 1080. At SG 996 one adds 10% of the original sugar volume (inverted of course) which should raise SG to 1004 now when the SG drops to 994 one adds another 10% and allows the SG to drop to 992 and so on until the total amount of additional sugar reaches 50%. One then allows the fermentation to proceed to completion hoping for an SG of 970 but in reality somewhere between this reading and 980.
To my mind practically all this could be achieved simply through the dissolving of the total amount of sugar with an invertase in 4.5 litres of water. For a total wash of 23 litres, 3 litres of this could be added to 17.5 litres of water containing the tomato paste the yeast is then activated at the same temperature as the water (80F) in a further 1 litre of water and added to the water sugar wash. A fish tank heater could be set to keep the wash at this slightly elevated initial temperature and the temp lowered after 48 hours when the wash goes into its’ anaerobic stage through the addition of the fermenter lid and airlock. The additional sugar could then be introduced through 5x300ml additions of the left over sugar mix at the appropriate SG readings.
I note that most suggest keeping the ABV sub 10% is this because of taste or the extra rise is seen as too much trouble? In my naivety I see the pump for continual circulation as being highly beneficial. It is my intention to apply this methodology to my next TPW unless, of course, someone notes serious errors in my thought process.

The next question arises from an article on the commercial distillation of Scotch Whisky.
3). A reference is made to new yeast not being able to put up with the rigours of high ABV. The remedy for the commercial Scotch whisky makers is to add “brewers yeast” from the top of a fermenting beer. Referring to Scotch this would be UK based info and as they mainly consume ale rather than lager – Does anyone know if there is a difference? Has this been tried? I can find no general reference.
The next question arises from general forum lurking and refers furfurals
4). It would appear that high temperatures when distilling either at the immersed element/wash interface or the bottom of the boiler/wash interface when heating with propane can burn suspended solids creating unpleasant flavours from the resultant furfurals. My question is, has anyone here tried heating the fermented wash in the still with recirculated water through a coil in the bottom of the still tank. And if so what sort of pump did they use to circulate the near boiling fluid? I note that the recirculated fluid could have its’ boiling point raised by adding salt to the fluid. Further I note that most commercial breweries use this method to heat the wash in their stills.
5). Oh and one last question – Has anyone tried the addition of salt to the fermented TPW wash prior to distilling so as to raise the boiling point of the water and create a greater temperature differential between water and ethanol. If so was it successful or did it introduce new problems?
Regards

[MR-E]

Whew, that's a lot of reading :techie-reference:
Your start & finish s.g will give you your a.b.v for the wash.
I don't use an air pump, I aerate the wash when I mix it & then let nature take over.
I stripped a T.P.W last night that was 14% & got 6ltrs of low wines @ 50% a.b.v.
I'd stick to Tried & Proven & then go from there.

Cheers :handgestures-thumbupleft:

[bt1]

Hello nb0s,

There's a fair amount of assumed knowledge in that write up. We need to focus on the things that are important here...keeping it simple.
Little concerned that selective articles are quoted as true, in context perhaps but as a general guide way off line.

Yeast timing
Dependant on yeast type (I’m a fanatic on yeasts) I'm not aware of any specialist yeast or general type require an aerobic hydration or growth phase of 48hours. If I did I wouldn't bother considering it as most general yeast are more like 30 mins. I've used 8 or so specialist yeast and none have this requirement.

Sugar addition
Adding sugars once inverted at specific intervals is way way too complicated. It has little or no benefit especially given even basic yeasts have sufficient osmotic tolerance to higher sugar concentrations. Having said that for a general yeast like Lowan's red can I stick to <-250g/lt and for specialist high tolerance yeasts =350gm /lt. Your start and finish SG's are more a function of convenience rather than specific measure measurements i.e. 2 x2Kg sugar is easy to handle store and use.
Additionally a constant temp which yeasts prefer would be lost by the regular additions.

I personally don't ferment with air locks in place, this is not the safe practice norm however, as I see no point in putting yeast under further stress. 1 inch of water =2.75 bar why do it. Once wash has stopped actively venting I then do plug to prevent infection risks.

Yeast nutrition
Higher osmotic pressures put strain on yeast cells. There are several common additives like Epson salts, DAP that help yeast deal with this.
A later addition of a food source would serve little or no purpose for yeast health.

Pt4. Heating still is a matter of costs and complexity. Sure it could be done but simply put if you rack well for several days and siphon with some care there's no issue here.

Pt5. We go to great care to induce flavour. Why stuff it up with adding a salt that will change pH and effect flavours.

In summary there's nothing wrong with getting it right but simplicity has to hold a value, especially in the smaller lower cost washes we use. We're not commercial here.
I'd suggest there would be more benefit from getting a good wash recipe and pH right before investing efforts in some of the issues raised.

bt1

[nb0s]

Thanks for that BT1 You are totally right i forget the KISS principle and get carried away in the minutiae. Trying to push to the extreme in small production to save 3 parts of SFA is really pretty silly. I will remember that.

Regards

[nb0s]

Thanks guys for the response.
As I said before I totally agree that I forgot the KISS principle. I came across this article by Dr Clayton Cone and followed his advice when really, pushing the outcome to the extreme is for the big boys. For we home distillers does it really matter if our processes are only partially efficient?
Having said that any discussion quoting Guru Cone becomes academic. His recommendation for 48 hours aerobic reaction time is to grow the cell wall of the yeast cell so as to withstand high ABV. But why not settle for 12% washes? - KISS. Similarly Cone states pitching the yeast direct probably kills 60% of the yeast but hey, as he states "it's a numbers game". When you have 20 billion yeast cells per gram and kill 60% you still have 8 billion per gram to get on with the job.
Again thanks I learned my lesson - KISS and enjoy the process.
nb0s
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[nb0s]

Hi BT1

I was just going over your response and feel I need to clear a few things up. Firstly let me say (once again) that I agree fully with you about observing the KISS principle - it will be central to my thought process from now on. I thank you for this. FYI The article I was quoting was by Dr Clayton Cone who as I understand it is regarded as the foremost authority on yeast. Still, quoting Cone is largely academic as we are agreed on the KISS principle and agree that efficiency can take a back seat to simplicity.
When I referred to the aerobic phase of fermentation I was not referring to the yeast (re)hydration process but the actual fermentation of the wash. Cone states allowing the fermentation process to be aerobic for the first 48 hours allows the cellular walls of the yeast to strengthen and withstand high ABV. Similarly he advocates the addition of yeast nutrients over time to grow a "stronger" strain of yeast. All only mentioned on an academic note.
The reference to salt was only for clear (neutral) washes to increase the variance in boiling point between the ethanol and water and is recommended by Alex Bokabob of the Bokabob still fame. A friend of mine is working on a (scotch) whisky wash and if I put salt in his wash ... well!!

Regards

[bt1]

Bloke,

couple on intresting points here. I can see the logic behind the salt and if for a neutral I can see the purpose.

On the yeasts issue I'll be back to you on this as it kinda does not sit right with my reading/understanding.

Any chance of a link to the orginal web site/article so i can read in context?


cheers
bt1

[nb0s]

Hi BT1

I have read quite a bit of Dr Clayton Cone - the links you want are
http://homedistiller.org/wash
http://koehlerbeer.com/2008/06/07/rehyd ... yton-cone/
In the second link I find the 5th paragraph of Cone's response interesting in so much as it helps to explain why we should always remember that we are doing something different to the brewers. What works for the brewers might not necessarily work with our high sugar washes.
Regards

[Divey]

Hello nb0s,

I personally don't ferment with air locks in place, this is not the safe practice norm however, as I see no point in putting yeast under further stress. 1 inch of water =2.75 bar why do it. Once wash has stopped actively venting I then do plug to prevent infection risks.

bt1

Wow, 1 inch of water = 2.75bar (39.88 psi) !! :)) I don't think so. I love my air locks. :-D

[bt1]

Yeh.
typo

kilopascal

[bt1]

Bloke,

I've read it twice but can't see how hydration lines up with the suggestion your making. In any case if you think there's a gain here give it a try. Let us know the results.

On rehydration yeast grows and forms the frothy film we see after first pitching. Yeast by itself will disperse into wash and start the process of sugar consumption/growth.

Even without stirring in yeast, (odd cos most folk do), the wash would become increasingly anaerobic as Co2 rises and strips O2 from the wash. By its very nature it would commence anaerobic conversion.

Could you perhaps explain the mechanism you intent to use to keep all but the top mm of the wash aerobic?

I also have issue with the idea; we pitch to achieve a result. The yeast we choose is either high tolerance specific yeasts or a general type. In either case we're not here to grow yeast we simply want an alcohol result. I still can't think of even a general yeast including crap like Tandico that would require 2 days of aeration. Our pitch rates are usually on the very generous side in any case.

Why would we do this? I manipulate temp and nutrition to get a finished ferment when I want it...i.e. 1 week or 2 weeks generally to fit in with free time. For one shot yeast use I can't see a benefit in terms of outcome, costs, quality or abv.

bt1