The Big Vodka Thread

Drunkas

@punkin said: I could recreate my build if you haven't seen it on ahb Philter.

+1

Philter

@punkin said: I could recreate my build if you haven't seen it on ahb Philter.

Thanks Punkin. Will take a look

punkin

I posted it here mate... Kegerator Beerfridge Build

Law_Of_Ohms

@Mickiboi

From the .DOC you posted...

"Arthur Yates Gro-plus Complete plant food"

Heavy Metals in Fertilisers @ Burke's Backyard

:-O

Mickiboi

@Law_Of_Ohms said: Mickiboi

From the .DOC you posted...
"Arthur Yates Gro-plus Complete plant food"

Heavy Metals in Fertilisers @ Burke's Backyard

:-O

I posted that recipe because I wasn't sure using garden fertilizer in something you are going to drink is a great idea. I have a Polar Bear water distiller at home for my drinking water so I'm pretty sure there would be no heavy metal carry over in distilling alcohol given the height of the column. Its the other lighter compounds that may be present that would worry me.

cunnyfunt

What prefecture were you in @cooperville?. I spent a bit of time over there too bumming it around while my GF worked:). Mostly Fukushima.

I just ran a wheat wash using 1118. It took 6 weeks at ideal temps:( I also looked into glycol chilling over the last couple of years, I personally think it would be worthwhile if you are chilling 200+liter capacity fermenters. But stc1000 and freezer is still very efficient for everything else.

If I was going glycol I would build a chiller out of an esky and a window type aircon.

I envy people that only have to worry about keeping their fermenters warm.

cooperville

Kanagawa Yep keeping things warm is easy

Grudaire

Lack of valine results in an increase in diacetyl as the pathway yeast take to produce valine results in said diacetyl, so if there is adequate valine for the yeast, the pathway is mitigated. Generally this is not much an issue for us brewers as barley is nutrient rich. I'd imagine people using low nutrient fermentables such as fruits or pure sugars would have issues with diacetyl. Certain yeast types produce more than others and colder temps can inhibit yeasts ability to uptake diacetyl, hence the diacetyl rest to aid in cleaning up lagers. I can get more in depth if you want as I wrote a paper on it once and could probably convey without ones eyes glossing over, just need to dig it up if you are interested.

cunnyfunt

Post it up @Grudaire I enjoy your posts.

vooharmy

I'm nearly ready to pull the trigger on a shiny new still! Burning question though, how many plates for a neutral!

Smaug

If run slow enough, you can collect 95% with relatively few plates, but I would not say the resulting spirit is neutral. Many of the German styled vodka makers are 18-22 plates.

Here in the US we try to recommend no less than 10 (actual or hypothetical) plates for a vodka like result.

punkin

4-6 plates with a 500mm packed section between the top plate and the reflux condensor is very popular here in Australia as a combination/jack of all trades still.

Common packings are either stainless scrubbers or scoria.

jbierling

@Smaug said: Here in the US we try to recommend no less than 10 (actual or hypothetical) plates for a vodka like result.

10 plates for neutral in one run or 10 for both a strip and spirit run?

Smaug

@jbierling said: 10 plates for neutral in one run or 10 for both a strip and spirit run?

That is really up to the distiller.

Davin Sherwood needs to distill at 95% but in no way wants his "sipping vodka" to be neutral. So he does a single run with 10 plates.

He distills mead made from wildflower honey and absolutely wants those floral notes to remain. By some interpretations, his finish product is not neutral enough.

As an aside, I am dieing to see how much power can be thrown at an 8er with ProCaps. May very well be possible to run a balls to the wall strip run with plates.

As per Dad's post on AD. Stranahan is stripping with a 4 plater and doing spirit runs with a pot still (for whiskey).

I can't get the possibilities out of my brain.

Smaug

@Smaug said: Davin Sherwood needs to distill at 95% but in no way wants his "sipping vodka" to be neutral. So he does a single run with 10 plates.

He would likely rather not take it off at 95% but felt compelled to do so to get into "vodka" territory.

He felt that without the use of the "vodka" word on his bottles, his potential customers would really not be able to identify and get their brain around what his product is all about.

His Vodka is amazing and I bet if he collected at below 90% it would really be special.

CothermanDistilling

@Smaug said: As per Dad's post on AD. Stranahan is stripping with a 4 plater and doing spirit runs with a pot still (for whiskey).

I wondered why the larger still had plates and the smaller one did not... pic is from May of 2006 when I got my eyes opened to what distilling was when my stepmom and I visited Flying Dog and were told about 'a distillery next door'....

I have 1.5 bottles of batch #2

grim

Why does it seem there is a new wave of oaked vodkas coming over from Europe? I'd tasted one example, and it was by no means distilled neutral, lots of grain flavor, absolutely a rye base spirit - with lots of oak, but little to no vanilla, or color. I'm guessing they passed it through charcoal after aging. It really didn't know if it was a whiskey or a vodka.

Interesting, but I'd never buy a second bottle.

captainshooch

That's what I call eye candy Michael!!! Just imagine people making vodka double run with 4 plates and others double run x-plates...as in Crystal Bean Stalk which turns out to be 36 plates in theory for a double run :-? However somehow it's all good. Go figure.

grim

How about something like SEBmature-L by Specialty Enzymes or Maturex by Novozymes?

I've been meaning to ask Sherman Owen about getting his hands on some SEBmature to run some trials to see if it's worth it. From a brewing standpoint, the big sales pitch is around turning fermenters quicker.

Grudaire

@cunnyfunt said: Post it up Grudaire I enjoy your posts.

Alright @cunnyfunt, I chopped some stuff up to post, so I apologize if it there are some funny transitions. Even then it looks like this will be a couple posts. I didn't have time to make it so your eyes won't glaze over...and obviously, as I'm a brewer and not a distiller this is for brewing beer not distilling; but, I figure what you do begins with brewing and the better the brewer the distiller is, the better the distillate can be...

My culmination on diacetyl research:

Depending on beer style, diacetyl has a flavor threshold as low as .04 parts per million (ppm) in the lightest lagers or as high as .1 ppm in stronger ales. Diacetyl is a ketone, more specifically a vicinal diketone (VDK), with a molecular formula of C4H6O2 (Fig. 1).

   O    O
   ||  ||
H3C—C——C—CH3

Fig 1

Yeast creates diacetyl in two ways, one being enzymatic and the other non-enzymatic. Both paths share similar beginnings as the yeast cell breaks down glucose into pyruvate in a process called glycolises. Once pyruvate has been created the enzyme pyruvate decarboxylase can catalyze pyruvate by decarboxylation (removal of CO2 from the molecule) with the reaction creating carbon dioxide and acetaldehyde. Some of the acetaldehyde then interacts with thiamine pyrophosphate (TPP, a vitamin B1 derivative) and magnesium in the reaction creating what is called the Acetaldehyde-TPP complex (active acetaldehyde) with the rest of the acetaldehyde remaining as free acetaldehyde.

Diacetyl can then be enzymatically created; however, this process is reliant on the enzyme diacetyl synthase which in some strains of S. cerevisiae is too inefficient to result in enzymatically produced diacetyl. In the strains with adequate diacetyl synthase the process works in a reaction between active acetaldehyde and acetyl coenzyme A (Acetyl CoA) and diacetyl synthase to produce diacetyl.

Active acetaldehyde + Acetyl CoA  diacetyl

However, this is more about knowledge of the fact as diacetyl creation through this enzymatic process is dependent upon yeast strains particular enzyme production and only is responsible for a small amount of diacetyl.

More significant to the creation of diacetyl is the non-enzymatic route which starts with active acetaldehyde reacting with pyruvate to create α-acetolactate. As seen in Figure 2 some of the acetolactate escapes the yeast cell where it undergoes oxidative decarboxylation to form diacetyl in a process believed to be a byproduct of the production of valine (Wainwright, 1973). The bad thing is that this reaction is at its maximum at a pH right around 5 according to Haukeli et al and this is the range we aim to put our beer.

Active acetaldehyde + pyruvate  acetolactate  valine  
                          
                            acetolactate  diacetyl  

Fig. 2

While the beer consumer may hate excess diacetyl, yeast love it since in the presence of the enzyme diacetyl reductase, yeast can metabolize diacetyl down into acetoin which can be further broken down to 2,3-butanediol. Do we care about these compounds? For current purposes not really, their taste threshold is many times lower than diacetyl so the most important thing to know is that if diacetyl is broken down into these compounds we no longer have to worry about butter beer.

Now, lets dust off our highschool chemistry class and discuss NAD and NADH. NAD is involved in the oxidation reduction (redox) reactions where there is a transfer of electrons. NAD is an oxidizing agent so it takes on electrons while NADH is the counterpart which is a reducing agent that gives electrons. Now that we know what we did not really want to know we can begin to understand the real trick to the reaction of diacetyls reduction to acetoin. As reported by Schwarz and Hang, this reaction uses NADH as the electron donor which means it is not a reversible reaction. Meaning that once diacetyl is broken down to acetoin there is no going back, it is a one way ticket to butter flavor avoidance. Before going on, there is one more little important tidbit when discussing diacetyl reductase. Sandine reports that diacetyl reductase is most active at a pH of 7.0 and becomes less active as the pH drops which impacts the ability of beer’s low 5 pH to clear out diacetyl.

Grudaire

Avoidance

The first area to avoid diacetyl is through proper cleaning and sanitization as gram positive bacteria including Pediococci and Lactobacillus can also create diacetyl (Fix); however, given they also produce lactic acid, sensory detection resultant of this form of bacterial contamination is easy, if it tastes like butter with a distinct sourness you probably have a bacterial infection. Since it is becoming increasingly understood by homebrewers and high quality sanitizers such as Starsan are readily available, bacterial infection due to poor sanitization should be an unlikely culprit for all but new brewers, those who intentionally introduced pedio and lacto into their brewhouse, and the “it won’t happen to me” crowd.

In one study lager yeast was repitched over four generations. In the first generation the diacetyl measured .15 mg/l on the first day and .12 mg/l on the seventh day. By the fourth generation the first day measurement was .36 mg/l and .40 mg/l on the seventh (Hoffman). That means from the first strain to the fourth strain the initial creation of diacetyl increased by 240% and day seven creation increased by 333.33%. As well, the data shows an inability to reduce ending diacetyl levels below initial levels by enzymatic reduction. George Fix reports that this effect, “parallel[s] increases in the level of respiratory-deficient mutants…[which] have lost their ability to reduce diacetyl.” For those that repitch yeast, these data suggest that an increase in diacetyl can result. If it does begin to become an issue and you do not have the proper equipment to isolate healthy yeast cells and propagate from that culture, it is time to start with new yeast.

Owades et al reported that the non-enzymatic creation of diacetyl can be inhibited by excess valine. This is because, like all creatures, yeast are lazy and will first seek to assimilate valine before generating its own supply. If it is not available the yeast will produce acetolactate in order to make valine. As discussed earlier, some acetolactate will escape the yeast cell and by oxidized into diacetyl. A yeast nutrient including yeast cells will provide a ready source of amino acids including valine and in doing so limit the production of acetolactate. However, this is a double edged sword as an introduction of excessive amino acids; whether it be from something simple like BCAA supplements or a more appropriate product such as yeast energizers can have a negative impact on the beer. That said, when it comes to using a supplement to feed the yeast, a Goldilocks balance must be struck, not too much, not too little.

Higher fermentation temperatures result in excessive yeast growth which results in excessive amino acid synthesis and thus excessive acetolactate production. However, fermenting cool also has drawbacks such as slowing fermentation, potential for stuck fermentations, and not enough ester production for the style. When getting a feel for how a yeast will behave you have the opportunity to experiment with temperature and cell count. Start off by using industry standard cell count levels and keeping in the yeast manufacturer’s temperature range guideline. From there you can change the variables to tweak the flavor profile, just remember to keep a constant.

Excessive pitching rates also have been shown to increase acetolactate levels which in turn result in more diacetyl. Part of this problem is that high pitching rates creates rapid fermentation shortening the amount of time acetolactate has to be converted into diacetyl. What happens in this situation is that during the bottling or kegging process some amount of oxygen is likely to get mixed into the beer. This normally is a minor problem as the beer will be consumed long before flavor problems arise. However, acetolactate readily oxidizes into diacetyl and with an over abundance of that precursor available due to the rapid fermentation process diacetyl will be created when bottling/kegging. At this point in time there will not be enough yeast available to clear out the newly formed diacetyl; voila butter beer results. However, there is contradiction in the argument that high pitching rates lead to more diacetyl as indicated by some research (Ersten et al). At the present it appears as yeast strain is the biggest factor when it comes to diacetyl production in relation to pitching rate. That said, the recommendation would be to start at industry standard pitching rates and adjust as needed.

Thinking in terms of strain selection, the flocculating habit of a strain plays a roll in how well yeast will clear out diacetyl as this is directly related to surface area. Highly flocculant yeast may need roused back in solution to create that surface area, but be careful to avoid adding oxygen into the system when doing so.

Remembering that acetolactate must be oxidized to become diacetyl brings up the issue of oxygenating wort. One might think that simply avoiding oxygen in the wort would be an effective means at limiting the production of diacetyl; however, as it should be coming clear, there is a balance with all things. Oxygen is critical for yeast health. The aerobic respiration yields far more energy than anaerobic fermentation, which is exactly what yeast need as they multiply. As well, oxygen is used during the lag phase to desaturate fatty acids which is critical to maintain cell membrane fluidity as the yeast multiply. This fluidity is critical since if the membrane is too rigid it can not as readily reabsorb diacetyl. On the other end of the process any remaining acetolactate will readily form diacetyl in the presence of oxygen. During bottling or kegging there is plenty of opportunity for this to occur. If you filter your beer there is no longer any means to remove diacetyl so oxygen contamination is more critical a consideration. For those who do not, adequate barrel or bottle aging will give the yeast time to clean out the beer.

As a side note, there is evidence that suggests copper interferes with the creation of diacetyl by interfering with the formation of active acetaldehyde (4).

PH is a factor that works against us. As noted earlier, diacetyl production is maximized at the recommended beer pH of 5.2 and the process that reduces diacetyl is maximized at a pH around 7. Increasing the pH is not a solution though as doing so yields problems such as the creation of haze forming polyphenols and extraction of tannins.

For those who lager, a diacetyl rest may be helpful. In this process the beer is raised to the low 60’s F for a day at the end of fermentation to take advantage of the increased diacetyl scrubbing effect of warmer temperatures.

Finally, ale should ferment to terminal gravity in about five days or less while a lager should not take more than seven days, with exceptions for certain styles. If it is taking longer to hit your terminal gravity this should be viewed as a symptom of poor fermentation which can lead to increased diacetyl production.

Grudaire

Conclusion

When taking diacetyl into consideration it is again a reminder that brewing is a balancing act between many different variables in our search for the perfect pint. The search should begin with just that, balance. Once the brewer has achieved consistency in their process they can begin to understand the characteristics of a yeast strain.

Diacetyl is a fact of brewing, no getting around it, just embracing it when needed and minimizing it when lagering. First things first, get rid of unwanted sources from things like bacterial and foreign yeast infections by being fastidious about sanitizing equipment. Next, care for your yeast and they will care for you. It is not enough to have proper pitching rates, you need proper pitching rates of healthy yeast. Give them yeast nutrients so they have all the needed trace minerals, amino acids, and vitamins they need to reproduce healthily, minimize unnecessary energy expenditure, and reduce the levels of acetolactate they produce. Give them oxygen, pure oxygen is the best if you can manage it, if not don’t get lazy on shaking that carboy. Keep fermentation temperatures in check. Let the beer sit on the yeast post fermentation to allow enough time to clear the diacetyl. Minimize any sources of oxygen after the lag phase.

Further reading:

Diacetyl: Homebrew Science

ADH1/YOL086C Summary

Development and Use of a Screening Procedure for Production of (alpha)-Acetolactate by Lactococcus lactis subsp. lactis biovar diacetylactis Strains (PDF)

On the occurrence of α-acetolactate decarboxylases among microorganisms (PDF)

Brewers' yeast pyruvate decarboxylase produces acetoin from acetaldehyde: a novel tool to study the mechanism of steps subsequent to carbon dioxide loss

Engineering of 2,3-Butanediol Dehydrogenase To Reduce Acetoin Formation by Glycerol-Overproducing, Low-Alcohol Saccharomyces cerevisiae

Fix, George J. Diacetyl: Formation, Reduction, and Control. Brewing Techniques. July/August 1993.

PATRIZIA ROMANO* AND GIOVANNA SUZZI Origin and Production of Acetoin during Wine Yeast Fermentation APPLIED AND ENVIRONMENTAL MICROBIOLOGY, Feb. 1996, p. 309–315 Vol. 62, No.

Wainwright, T. 1973. Diacetyl—a review. I. Analytical and biochemical considerations. II Brewing experience. J. Inst. Brew. 79:451–470.

Baumes, R., R. Cordonnier, S. Nitz, and F. Drawert. 1986. Identification and determination of volatile constituents in wines from different vine cultivars. J. Sci. Food Agric. 37:927–943.

S. Hoffmann, Brauwelt International (Brauwelt/Verlag, Nuremburg, Germany, 1985).
Process for brewing beer while enhancing yeast growth

OWADES, J. L., MARESCA, & RUBIN G, . (1960). Nitrogen metabolism during fermentation in the brewing
process. II. Mechanism of diacetyl formation. American Brewer 93, 24-26.

brewsmith

Great post @Grudaire, lots of good info here. As a pro brewer myself, my background is in beer fermentations, and the conditions some of the commercial scotch and bourbon fermentations ungergo blow my mind. However, years or decades in wood surely help to mellow out a lot of funky flavors made early on. Seems to me however, that an expert brewers approach to clean, healthy and controlled fermentation paired with an expert distillers' cuts would make for a fine spirit that wouldn't need to spend so much time aging to hit its prime.

Grudaire

@brewsmith said: Great post Grudaire, lots of good info here. As a pro brewer myself, my background is in beer fermentations, and the conditions some of the commercial scotch and bourbon fermentations ungergo blow my mind. However, years or decades in wood surely help to mellow out a lot of funky flavors made early on. Seems to me however, that an expert brewers approach to clean, healthy and controlled fermentation paired with an expert distillers' cuts would make for a fine spirit that wouldn't need to spend so much time aging to hit its prime.

Barrel aging is a beast in of itself. Esters, phenols, and alcohols react with the wood and micro oxygenation occurs completely changing the character. When I barrel age things like a barley wine I intentionally let the beer ferment warm knowing those higher alcohols and pronounced esters will age nicely and bring in a whole new character. However, clear spirits don't have the benefit from barrel aging so I could only imagine that the cleaner the ferment the cleaner the end product, just like us brewers specialize in. I think it would be fascinating to team up with a distiller and see what we could do working together.

grim

@brewsmith - The big question mark in my mind is which funky flavors do or don't carry over in the distillation process. I suspect this is one of the major reasons most large distillers can get away with a fermentation process that would make a brewer scream in agony. Some of the major brewing flaws are simply irrelevant post distillation, some flaws may actually be desirable. Same goes for mashing steps that are of less importance post-distillation (protein rest to improve clarity for example).

I've drank lots of fermented wash pre-distillation. Yeah, I said it. It wasn't on a dare either. Funky, not funky, lacto, you name it. Always trying to understand what flavors carry over, and which don't. Given sufficient lab equipment and a PhD, it's probably an easy question to answer, but I haven't found a PhD who wants to get paid in whiskey yet, so I rely on sensory analysis ... yum.

Always a disappointment to have a wash with a really interesting flavor, only to have that flavor lost in the background post distillation, or just not come over at all.

punkin

Lacto comes across for sure. Although that could be one of the complimentary flavours you refer to in some cases. I can always taste a hint in the white dog if it's there.

Not sure what plays in plain corn souring ala pint's method, but if it's lacto like he says it's a different one to the dusty top crop infection that i think of as lacto. It's a sour milk and it carries over real well and is definitely a taste i like.

brewsmith

This thread is perfectly relevant to my two leading interest at the moment, wild/brett/sour beers and distillation. Obviously the world of fermentation is vast as many craft breweries experimenting or even specializing in sour and wild ales, and there is certainly a world of opportunity in experimentation to be had between this and distillation. Intentional use of wild yeast, bacteria and bugs produce wonderful flavors and aromatics but possibly some things that may not be so pleasant. However, combined with the ability to make cuts in distillation allow you to be choosier yet as to which of those flavors and aromatics you retain. What first comes to mind for me are the wonderful pineapple aromatics I have gotten from pure brettanomyces ferments that would be wonderful if captured in spirits...

Bit of a tangent there, but I will be certain to keep everyone apprised of my further dabbling into the subjects.

Also, @Grudaire, that's an interesting concept applying this distillers tactics back to brewing wood aged beers to get those whiskey/spirit flavors in the beer from it's own interaction with the wood. Much room for play here :)

Smaug

One of my favorite Japanese (Hitachino Nest XH) beers is finished in Sochu barrels. Ordinarily when I think of great beer I do not think of Japanese beer, but I find this beer to be spectacular.

Myles

Can I take this right back to the start to clarify what sort of vodka you are interested in? There seem to be two distinct styles. One is a clean bland spirit for mixing with other products, the other is intended for drinking without mixing and often retains a slight flavour, and sometimes a distinctive "feel" in the mouth.

For the first I most often re-distill feints from previous runs and very rarely ferment specifically for it. I suspect fermentation for this type is not really important.

For the second however fermentation (grain based?) is likely to be an issue.

Myles

I have to agree with @grim. I just don't like the oaked vodkas and am not sure about the oaked grappa's either.
I really like clear fruit brandy and some of the grain vodka, and feel that oak has its place - but vodka and grappa is not where it is at.
However, that is just my opinion.