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Classic Lloyd

Sourcing bacterial strains for rum fermentations

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Potential microbiological basis for carotenoid precursors in cane and rum can potentially be due to Rhodotorula.  This has been implicated in Cachaca and Tequila/Agave spirit as well.

beta-Carotene production in sugarcane molasses by a Rhodotorula glutinis mutant.
https://www.ncbi.nlm.nih.gov/pubmed/11571614

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Several wild strains and mutants of Rhodotorula spp. were screened for growth, carotenoid production and the proportion of -carotene produced in sugarcane molasses. A better producer, Rhodotorula glutinis mutant 32, was optimized for carotenoid production with respect to total reducing sugar (TRS) concentration and pH. 

EFFECT OF SOME SUGARS AND AGRO-INDUSTRIAL BY- PRODUCTS ON CAROTENOIDS PRODUCTION BY SOME YEAST STRAINS OF RHODOTORULA SPP.

http://srv4.eulc.edu.eg/eulc_v5/Libraries/UploadFiles/DownLoadFile.aspx?RelatedBibID=ODQ2ZDQ0NDAtM2U0OC00ZjMzLTkyMTgtOGU5MWQ1MGI3NGZkX2l0ZW1zXzEyMTIwNzM3XzM1Mjg5MV9f&filename=1097.pdf

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Several microorganisms, including bacteria, algae, moulds and yeasts of the generaRhodotorula, Rhodosporidium, Sporobolomyces and Phaffia are able to produce carotenoids naturally( Frengova and Beshkova, 2009).

Microbiology and physiology of Cachaça (Aguardente) fermentations

https://link.springer.com/article/10.1023/A:1010225117654

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Cachaça (aguardente) is a rum-style spirit made from sugar cane juice by artisanal methods in Brazil. A study was made of the production, biochemistry and microbiology of the process in fifteen distilleries in Sul de Minas. Identification of 443 yeasts showed Saccharomyces cerevisiae to be the predominant yeast but Rhodotorula glutinis and Candida maltosa were predominant in three cases

Did Fahrasmane and Ganou-Parfait simply miss it in "Microbial flora of rum fermentation media"?

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Don't have access to this one, but also indicates β‐Damascenone formation from precursors during distillation, in a way that is aligned with the Shochu paper above.

Influence of the Production Process on the Key Aroma Compounds of Rum: From Molasses to the Spirit

https://pubs.acs.org/doi/pdf/10.1021/acs.jafc.6b04046

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(E)-β-Damascenone showed by far the highest OAV (3280) in rum. Although this compound was determined already in molasses, its concentration increased significantly during distillation, indicating a thermolabile precursor.

Perhaps the specific pathway?  Xanthophylls naturally occurring within sugar cane, as well as in corn.

Thermal degradation of a neoxanthin-like xanthophyll to the potent aroma compound beta-damascenone

https://www.researchgate.net/publication/295324888_Thermal_degradation_of_a_neoxanthin-like_xanthophyll_to_the_potent_aroma_compound_beta-damascenone

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I have a bunch of the papers behind paywalls. It is quite the rabbit hole. When you experience these compounds isolated, they are quite extraordinary. I wrote two very funny blog posts where I introduced them from the perfume industry perspective. They very much live up to Arcadi Boix Camps idea that he immediately felt the desire to introduce them to Plato!

One of the nice things about them is that targeting them goes hand in hand with targeting esters.

Wayne Curtis just wrote an interesting article about the state of tequila rediscovering itself. When they describe character they cannot really pin down through their change in process, even though they have GCMS, a lot of what they are doing may be maximizing these carotene based aromas. The heritage Tahona process (as opposed to diffuser) likely comes with greater time under heat. They also put some shredded agave in the ferment. These compounds are very challenging to look at and only university based labs are sophisticated enough. The birectifier gives a cheap window, but only allows you to do an organoleptic survey.

To go to yet another Daily Beast article from Lew Bryson, where I think his argument is flawed, the difference between pot and continuous column stills (beer still) may be their ability to target these hard to reach compounds. A pot still has longer time under heat with increasingly concentrating acidic conditions. If a continuous column has a fusel oil separator, they may be inadvertently trashing these compounds. Two strikes against the continuous column, but if the pot operator doesn't know what they are looking for, how do they know they are maximizing potential? The sour mash process is quite special, just like the dunder process. All that time under heat invested into the stillage can create high value aroma that can be unlocked by the next fermentation.

Both articles and the discussion here, show these compounds are going to move to the top of distillation discourse and very much fit in with everyone's pursuit of esters. I hope they present opportunities for smaller producers to really excel and rival large productions.

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The Formation of β‐Damascenone in Sweet Potato Shochu - Yoshizaki - 2011 - Journal of the Institute of Brewing - Wiley Online Library

 https://onlinelibrary.wiley.com/doi/abs/10.1002/j.2050-0416.2011.tb00464.x

 

 

I was just reading this paper today!  It made me wonder what role enzymes play in the overall creation of esters and damascenone.  Like - would prefermenting some of your ingredients to prep your main fermentation (a la the use of koji in shochu production) result in higher ester output, in addition to higher alcohol output?

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3 minutes ago, bostonapothecary said:

One of the nice things about them is that targeting them goes hand in hand with targeting esters

It seems like the same process will yield both compounds through inverse reactions - Condensation (removal of water) in esters and Hydrolysis (addition of water) in Carotenoids, both involving acids or enzymes. Also long distillation times seem to raise both ester and damascenone counts.

 

8 minutes ago, Classic Lloyd said:

would prefermenting some of your ingredients to prep your main fermentation (a la the use of koji in shochu production) result in higher ester output, in addition to higher alcohol output? 

I believe that part of the premise of stillage - be it fresh, seasoned dunder or muck. It helps build precursors to other more interesting compounds. SCD/BA - is that how you're interpreting it? As for higher alcohol output - do you mean volume or fusel alcohols? I think you mean volume - I can't answer that as I'm not sure. Interesting question - you mean like a starter or something else?

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12 minutes ago, Foreshot said:

I believe that part of the premise of stillage - be it fresh, seasoned dunder or muck. It helps build precursors to other more interesting compounds. SCD/BA - is that how you're interpreting it? As for higher alcohol output - do you mean volume or fusel alcohols? I think you mean volume - I can't answer that as I'm not sure. Interesting question - you mean like a starter or something else?

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Well, with koji-malted fermentations, the koji keeps producing enzymes even after the fermentation has started - mostly amylase, but also a whole host of other enzymes (lipase, protease, beta-glucanase) which dries out your fermentation and often raises attenuation above 100%. I'm thinking about loud, but maybe some dunder can have building blocks for chemical / enzymatic transformation, in addition to the bacteria and concentrated ingredients I'm familiar with reading about.

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1 hour ago, Foreshot said:

I don't know much about Koji. Seems like interesting stuff though.

Oh yeah - very much so, although probably less relevant to rum. (I use it mostly for protein-rich fermentations.)

Really, I’m trying process all the great stuff in the thread. My original question was really “where do I find bacteria to produce butyric acid esters” and it’s evolved to “how do I create the most conducive environment for overall ester creation?” The shochu article has me wondering, specifically, “how I can utilize dunder to set up a successful fermentation?”

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13 hours ago, Classic Lloyd said:

Sort of relevant - a friend of mine using a mix of an enzymatic mold and yeast to create esters on quince:

https://www.instagram.com/p/Bsss6e2AcHQ/

 

I wrote about Koji's historic use in whiskey as a follow up to some other whiskey documents. It would be awesome to introduce the Noma team to the birectifier. A recent case study shows that it may be a viable way to analyze vinegar. They could also likely take that quince, extract it's aroma with ethanol, then fraction it to gain insights.

Reading through the carotene derived aroma literature, there may be spectacular potential in odd substrates if grand arôme ideas are used as opposed to more straight forward fermentation/distillation templates.

Arroyo's mold was actually an alt-yeast that metabolized proteins to produce the high value ester, ethyl-tiglate, which smells appley. My microbiologist colleague has isolated it and it's looking like it may be the easiest to work with grand arôme fermentation complication.

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There is such a compelling desire to want to hone in on a a process, a technique, a molecule or class of molecules, and want to implicate that as being the most important factor in an outcome.  To try to chase it all the way down to the source, define it, master it, optimize it, in hopes of achieving some super-optimal end goal.  Believe me, I love this stuff, the hunt is almost as exciting as tasting the first drops of distillate.  The fact is, it's never so simple, and it's far more likely that optimal goals are not traced back to single things.  In fact, it's more likely that we are turning 2 or 3 dials, on a control panel with hundreds of dials.  As much as we think a single dial is the dial of critical importance, it's not.  Even with the most sophisticated analytical techniques we have today, it still remains impossible to replicate a spirit by looking at it's chemical fingerprint, because given all the variables we know, there are still more variables we don't.  It doesn't even matter, because even if you could achieve some optimal goal, you still have the human side of the equation, individual preference and perception of flavor, which is so variable that defining "optimal" becomes futile.  You can look at the history of rum, and the overwhelming trend towards clean rums as embracing this trend, realizing that emphasizing "character" means potentially alienating customers, because of individual preference.  Just like the vodka trend through the 70s and 80s hit the dark spirits industry like a freight train, there's an overwhelming trends towards eliminating character, because character eliminates customers.  There's a reason Smirnoff wins every single double blind vodka taste test, because it contains nearly zero objectionable character - and keep in mind, what you love, someone else might find objectionable.  All these things we do start to run contrary to that, and there is nothing wrong with that.  But always keep in mind that Bacardi is selling 200,000 bottles of white rum for every bottle of high hogo that you can make, let alone sell.  We are talking niche, and we are talking about passion products, not profit products.

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I'm in a particularly nihilistic mood this morning.

Consider the fact that Arroyo may have been wrong.  We hold one of his works as being incredibly influential, US Patent US2386924A - Production of heavy rums.  However, I've never found any evidence that it was ever licensed and put into production commercially.  @bostonapothecary - Perhaps you've come across some evidence that this was ever licensed by a commercial distillery, and actually had a bottle produced through his patented process?  If so, please share, I've never seem anything that indicates it was ever even licensed (though that information is likely not in the public domain).  Reading "between the lines" of some of Arroyo's later papers, he seems to be giving up on the heavy rum process, giving up on Pombe as being key, giving up on bacteria being key, and later focusing on hybridized yeast as being the key factor.

Now, sure, It's possible that existing commercial producers simply didn't care about his patent.  Why bother licensing his process if you were a commercial distillery that was already doing it.  It could have been due to market trends, his timing may have been too late, with clean industrial rums becoming far more commonplace at the time.  Or, he was wrong, and his process simply doesn't deliver what we hope it could deliver.  Whatever the reason, it's arguable that his patent was a commercial failure.  Keep in mind, this was not an academic paper, this was a patented industrial process.  We're not drinking "Arroyo Process (TM)" heavy rums today, and it's questionable if one was even ever produced.

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This is the only piece of evidence I’ve ever found, and it’s not likely these producers were making heavy rums.  Given the focus on production and capacity, this seems like more traditional production consulting.  Arroyo looks to have run this ad in the Sugar trade mags a few times.

B890E224-F269-4451-AEC6-26ADD994A4EE.jpeg.72e57b832c66d5cd53bd33c3c7c0f3d8.jpeg

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58 minutes ago, Silk City Distillers said:

This is the only piece of evidence I’ve ever found, and it’s not likely these producers were making heavy rums.  Given the focus on production and capacity, this seems like more traditional production consulting.  Arroyo looks to have run this ad in the Sugar trade mags a few times.

B890E224-F269-4451-AEC6-26ADD994A4EE.jpeg.72e57b832c66d5cd53bd33c3c7c0f3d8.jpeg

I personally favor a lot of the Jamaican ideas over the Arroyo ideas. Arroyo got his ass kicked by numerous factors. He also had numerous successes that are very easy to take for granted. For starters, he died untimely which doesn't help promoting something very complicated. Then his ideas for heavy rum came at a time where the post war economy demanded affordable ubiquitous commodity products. Puerto Rico also had the tax rebate so they focused on that comparative advantage and obliterated everyone else in the commodity sector. There was a super cool talk on "Spanish style rums" in Jamaica this past October. No style was discussed. It was all just startling efficiency and economy. At some point Arroyo's papers were lost and barely referenced again even as others waded into the same territory.

Even though no one made heavy rum, the Arroyo victories are everywhere. Continuous stills got filled with encrustations until his molasses pre-treatments were adopted. Many distilleries use centrifuges but Arroyo paved the way. People used simple bakers yeast and paid no attention to pitching quantities that impacted fermentation rate. Yeast nutrient use was a mess. Little attention was also paid to yeast selection even for fast fermenting light rums. Arroyo also taught about record keeping to prove efficiency. Many at the time were running continuous stills inefficiently and losing a ton of alcohol in the stillage with few records to isolate the loss. Arroyo even taught people about even congener composition when before they were just winging it. His stamp is all over fast fermenting economy rum, quite a lot of precedents.

Arroyo elaborated the birectifier, but I think no one used it except one guy in Trinidad in 1953 for a PhD dissertation. Rum distilleries really cheaped out on labs until they learned from the Seagram crowd. By that time, chromatography was becoming fashionable.

There is significant opportunity today because analysis is faster and much cheaper. Fine wine was born in the lab (Grgich, Stag's Leap, Chateau Montelena) and fine distillates will be the same. Right now people that are frustrated are conducting zero analysis. One of the best things you can do is deconstruct role models to learn the grammar. Back in the day they had a lot of trouble obtaining exemplary samples and now we can go to any corner liquor store. As mostly non formally educated biochemists, we also have the benefit of YouTube University and inter library loan. One of the big complaints in the 20th century was how scattered the literature was, but now it is aggressively being collected and shared.

The heavy rum patent may be some kind of weird tease, but is anyone really using 21rst century opportunities in their operations? When I discuss a heavy rum production idea, I've got a comprehensive $3000 analysis solution to examine it. And true, yet another $4000 for a titrator. My goal for 2019 is more case studies and model ferments. Bring it to life backed up by the most basic analysis.

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"Fine wine was born in the lab (Grgich, Stag's Leap, Chateau Montelena) and fine distillates will be the same.  "

I don't understand your use of the word 'fine' I guess. The idea that there was no 'fine' wine before the 70s is ludicrous.  

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4 minutes ago, JustAndy said:

"Fine wine was born in the lab (Grgich, Stag's Leap, Chateau Montelena) and fine distillates will be the same.  "

I don't understand your use of the word 'fine' I guess. The idea that there was no 'fine' wine before the 70s is ludicrous.  

It isn't when you consider California and its transformation under figures like Maynard Amerine and André Tchelistcheff. Wine with with fine ambitions as opposed to commodity existed but was extremely limited before the 1970's. When you read all the memoirs and oral histories, the pattern is that all the players were adept lab guys that spent time working with Tchelistcheff, Mondavi, or sitting in on night classes at UC Davis. That lab work also wasn't too wild. It was a lot of tracking titratable acidity and sulfur dioxide.

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You would need to specify fine 'californian' wine, Europe has had 'fine' wine by any reasonable definition since about the 3rd century. In some of those oral histories you will find reference to a variety of 'fine' or ambition wines produced in California prior to prohibition and even fine distillates like pinot noir brandy. The creation of 'Fine' beverages might be aided by lab work, white papers, university research etc but what ultimately matters (as Silk mentions above) is intention, palate, and an understanding of your materials (however derived). 

 

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I didn't chime in earlier, but I read your site and really enjoy it and appreciate the work you put into it. That statement just really rings hollow for me. 

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Hey, first post, but been lurking. Setting up a distillery in Louisiana. I've learned a lot from this forum. 

I'm following this thread with a lot of interest.  My background is in microbiology, I'm currently an MD.  Please allow a tangent for a second to serve as an analogy.  Breast milk is a complex consortium of enzymes, chemicals, and a microbial biome.  The best analogy I've heard for breast milk is that it is a symphony and each of those enzymes and chemicals are playing a part in the symphony.  Formula companies can add things, albeit gluco-oligosacharides, fructo-oligosacharides, lactoferrin, etc, but they are just adding noise or instruments and the outcome is a product inferior to breast milk.  The cello line from the 1812 overture doesn't make sense unless you have the rest of the instruments. But neither do the rest of the instruments without the cello line. 

My fear of stressing individual chemical esters or pure isolates of specific bacteria is that you end up creating noise instead of a symphony.  And I think of a fine wine or a great spirits as a symphony.  The microbial ecology of a dunder pit is fascinating.  Each of those individual species in the pit is playing a part. Each of the esters in rum may need a different compound to make it mature "appropriately." Species x in the dunder pit may rely on species Y to create the precursor compounds that species x metabolizes into what you desire.  

To tie it back into the wine talk, I think terroir, especially when we talk about it in context of distilled spirits, may have a lot to do with the individual microbial biome of y'alls (and hopefully soon my) distilleries.  Many of the bacteria in any biome are un-culturable by traditional culture techniques as PCR has demonstrated.  

Keep up the talk, its fascinating and I am learning a lot!

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35 minutes ago, JustAndy said:

You would need to specify fine 'californian' wine, Europe has had 'fine' wine by any reasonable definition since about the 3rd century. In some of those oral histories you will find reference to a variety of 'fine' or ambition wines produced in California prior to prohibition and even fine distillates like pinot noir brandy. The creation of 'Fine' beverages might be aided by lab work, white papers, university research etc but what ultimately matters (as Silk mentions above) is intention, palate, and an understanding of your materials (however derived). 

 

I think I made some assumptions and chose California's figures at the Judgement of Paris which is an entrepreneurship story which inspires a lot of distillers. Europe having fine wine is a bit messy. It definitely had them, the best, and was no doubt was direct inspiration for California's pioneers, but Europe also had a sea of local wines riddled with faults. The Europe we know today which is a beautiful sea of diverse consistently produced fine wines is probably because of incredible oenology education programs and small scale labs at small properties. Knowledge and awareness of how sulfur acts on wine is not enough, you still need instruments to measure sulfur and wield the knowledge.

Old California wine history has some problems which is why the oral history series was created. Tchelistcheff and Amerine gives us really plain looks at the state of the best early California wines (very few and their stories are incredible) while Leon Adams muddies it and gives us another. Adams, running the biggest trade group (the wine institute), was an obsessive propagandist. He admits to fabricating a lot of early wine history to build mythology and erase the notion that wine was a salvage product (table grapes > raisins > wine) drunk by bums on skid roe. His two oral histories are completely insane.

I don't think California had any truly extraordinary brandies until the Remy Martin Scramsberg project and there are cool oral histories on it as well as two excellent James Guymon lectures by Eli Skofis and Robert Léauté.

The cool thing about analysis is it both reinforces and turbo charges intuition so you know when to invest the time and when to not. It is the key to building a palate and understanding materials. Birectifier analysis is very cool because its most basic form is organoleptic. Working with it constantly builds you palate.

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I don't think it's fair or accurate to say European wine is or was riddled with faults', things that one might consider a fault in some context are important parts of terrior or wine character for some styles. The 'international' style of flying winemakers driving things from a lab is starting to get quite a bit of push back as people become interested in historical, authentic flavors of place (is brett, va, oxidation, a fault? depends on who you ask). By the same token many of the rums, mezcal, and baijiu that incorporate some of the techniques discussed here would be judged hugely faulty by many palates. That's what I mean about intention. There is no 'ur'-spirit, and research will not uncover the holy grail of flavor that everyone agrees is the best, because taste is subjective and context matters. It's very useful to have the tools to figure out how to make more cinnamon flavor, but that doesn't mean cinnamon tastes better than vanilla. 

I've read Skofis's transcript and several of the other ones which were all interesting, I don't recall the specific name but there was a CA winery making pinot noir brandy in the 1880s that took prizes at the World's fair or something like that. From his transcripts I gathered not that they didn't know how to make quality brandy, but that there was no market for it which is a pretty different problem.   

Anyways, back to bacteria talk.

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The University of Bordeaux was just as aggressive as UC Davis in increasing the quality of European wines. They had storied thinkers like Denis Dubourdieu who just passed recently. They eradicated a lot of very specific flaws through education. A flaw is not a flaw until you attach symbolic concepts like regrets or missed opportunities. A Dubourdieu project was eliminating the bell pepper aroma from certain varietals (Carmenere). Many thought it was site specific terroir, but it was revealed to be removed by pruning techniques. Removal of the character added a lot of value to the grapes.

The international style is a whole different story, but related to low risk wine making, and fad flavors. That style doesn't dream enough and no wonder it wore out quick. Even in the center of the terroir scene, a problem is that ordinary wine making flaws have been so significantly eradicated that when they reappear, elite critics are mistaking them for terroir. What is ordinary becomes briefly extraordinary until the regrets and missed opportunities are re-attached. Jamie Goode, who wrote, Authentic Wine: Toward Natural and Sustainable Winemaking, just wrote a book about understanding faults in wine

Mezcal, like so many spirits, are well in the realm of acquired tastes. We have fun looking at the production of eccentric spirits because they seem very risky and yet it mostly works out. Many of them do have flaws and Mezcal is often flinging anything at consumers hoping they will try a single bottle before moving on. We often don't have the language to separate faults from acquired tastes.

One cool thing about the flavors in rum, particularly rum oil, is it was absolutely chased. Jamaican rums and Batavia Arracks fetched the highest amount of money in the world for spirits ever. This was leaps and bounds above what other spirits got at the same time. Very certain rums were the pinnacle of luxury consumption so we know something about the value of what we're chasing. It really captivated imaginations.

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Gentlemen, let's not go too far off on a tangent on the quality of wine. This the most interesting thread we've had on fermentation and flavor development I think ever and I would not want to have it get too far off that subject. So to get back to that...

5 hours ago, thomasd said:

My fear of stressing individual chemical esters or pure isolates of specific bacteria is that you end up creating noise instead of a symphony.

 

11 hours ago, Silk City Distillers said:

There is such a compelling desire to want to hone in on a a process, a technique, a molecule or class of molecules, and want to implicate that as being the most important factor in an outcome.

That ^^^^^ (both of them)

I am in agreement with both sentiments. It's the law of unintended consequences that when we aim for one thing in such a complex process as fermentation we will upset something or many something elses (grant me some poetic license here, I'm on a roll). But we still need to experiment and see what happens. It just has to be with an open mind that honestly critiques the results.  To me the worst thing that could happen is that we end up with a process like most fast aging process that hit one aspect of an aged spirit and fails on so many others - As ThomasD said, it creates noise, not a symphony. SCD said it more scientifically.  I want to make some really esoteric spirits. But I don't want to make a gimmick. I want to make some that has all the right aspects in the right quantities that make a spirit great. Most whiskeys on the market now are really good. But it's the same process without much innovation. Our great-grand parents could, and did, make great spirits too in basically the same way. I want to do something new.

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