!!! -> Need questions for an interview on esters ASAP!

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!!! -> Need questions for an interview on esters ASAP!

Postby Single Malt Yinzer » Tue Oct 10, 2017 5:54 am

Hey everyone,

I read this article http://www.gobourbon.com/bacteria-and-your-bourbon/ and I ended up emailing the author - Dr. Patrick Heist.

Dr. Patrick Heist is the co-owner and Chief Scientific Officer for Ferm Solutions, Inc. and Wilderness Trail Distillery. Ferm Solutions provides yeast and fermentation expertise to distilleries all over the world and is housed at the state-of-the-art, Wilderness Trail Distillery.


http://www.wildernesstracedistillery.com/
https://ferm-solutions.net/

He agreed to answer our questions on esters! I need these questions asap as I want to compile them and send them to him tonight. I'll have my own but want to make sure everyone gets a chance to ask a question.

How awesome is this????

SMY
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Re: !!! -> Need questions for an interview on esters ASAP!

Postby der wo » Tue Oct 10, 2017 7:45 am

Single Malt Yinzer wrote:How awesome is this????

Depends on his answers. :lol: If he brings some light only to one of my questions, it's more than awesome.

1. The glue smell of Bourbon is obviously ethyl acetate. Produced by vinegar bacterias. Open fermentation seems to be the reason. But why even young Malt Whiskies doesn't have it? They also are fermented open normally. Is the key the fores cut of pot distillation vs no fores cut in continuous distillation. Or are there other causes like the warmer climate in Kentucky than in Scotland?

2. How is backset of sour mash Whiskey stored? Open, sterile? And how long until they add it to the mash.

3. What role plays the yeast selection, what bacterias, what the circumstances (temperature, fermentation duration for example).

4. Produces the yeast esters or acids (which are esterified later)?

5. Is the bubblegum smell of many Irish Whiskies butyric ester? If yes, why? Why in Irish, why not in Scottish Whisky?

6. Are there Bourbon distilleries using acids (besides backset) to rise esterification? Which acids? Sulphuric acid?


Perhaps I'll find more questions and add it later.
In Germany we say "asking someone holes in his belly" when behaving like me here. :ebiggrin:
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Re: !!! -> Need questions for an interview on esters ASAP!

Postby OtisT » Tue Oct 10, 2017 8:00 am

I have some, and will compile them today for you. Thanks for doing this.

Wish I could join the call, even if just listening. Any chance you and he will allow the QnA to be voice recorded? I'm sure his answers will be longer and more nuonced than you will have time to write and type for us. Just a suggestion.
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Re: !!! -> Need questions for an interview on esters ASAP!

Postby Single Malt Yinzer » Tue Oct 10, 2017 8:28 am

I'm going to be using a Zoom meeting (same as GoToMeeting). If he is ok I will record and post it. OtisT - I will PM you the time and info. If he is ok with it I'd be happy to have you on with us. We're both East Coast so it may be a bit early for you.
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Re: !!! -> Need questions for an interview on esters ASAP!

Postby OtisT » Tue Oct 10, 2017 12:39 pm

First, please tell him “Thank You”

These may be too much, or too wordy. I won’t be offended if these don’t get asked.

His article refers mainly to esterification during ferment. I hope he will consider my mostly post ferment questions below. Also, some of my Qs are pretty specific, so generalizations or just a point in the correct direction would still be appreciated.

Question (area) 1:
I have begun to follow and try the various discussions on HD as to when, where, and how to use backset to create esters. My first question would be to ask his opinion on which of these methods may be most promising (or not) at producing more/different esters, and why? His article covers bacterial infections well, so this is excluded here.
• Backset added pre-fermentation
• Backset added direct to low wines prior to spirit run. (follow-up. Does he think any esterification is taking place because of high heat during the boil?)
• Backset mixed with feints alcohols. Let age (or not) and add to low wines
• Backset added to your cuts

Q2:
If mixing backset directly with alcohol (not ferment) for the purpose of creating esters works:
• What kind of ratios/concentrations/measures are needed to foster esterification? (ex. Should we need to adjust PH, dilute alcohol, etc.)
• Should we be amending this chemical mix to foster esterification?
• Time/Temp for reaction to complete? (varies by method?)
• What alcohols would be most promising for esterification and why? Either by alcohol name or maybe simply considering fore shots, heads, hearts, tails? Does it matter?

Q3:
The article says higher ABV can kill bacteria needed for esterification, and also says the ester creation process takes place over time in the barrel. 62% must not enough to kill all the bacteria (I hear some can live in space) No direct question here other that “hugh?” I am guessing that some bacteria do survive at 62% ABV and that the process is just slow.

Q4:
Personal Preference. What specific esters would be in your “perfect” Bourbon?

Related, but off subject Question:
How do you identify ester smells/tastes? Please briefly describe your process of isolating and identifying these wonderful smells/tastes. Underlying question is how do we learn to do this? Is there a book, specific reference chart, site/blog that he thinks describes this well? [This is extremely difficult for me. I am great and comparing/contrasting, but in isolation naming a smell is not my thing.]

Extra Credit Question:
Teach us a new ester trick we can try. Anything he thinks is cool with esters that an enthusiast may find to cool. Maybe a yeast/recipe/process that makes a product that tastes like a peach, or some such PHD level magic ;-)

Thanks, Otis
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Re: !!! -> Need questions for an interview on esters ASAP!

Postby OtisT » Tue Oct 10, 2017 12:41 pm

Single Malt Yinzer wrote:I'm going to be using a Zoom meeting (same as GoToMeeting). If he is ok I will record and post it. OtisT - I will PM you the time and info. If he is ok with it I'd be happy to have you on with us. We're both East Coast so it may be a bit early for you.


Cool. I will look for the meeting info in PM. Early is no issue, unless it's when I get my boy ready for school. Thanks. Otis
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Re: !!! -> Need questions for an interview on esters ASAP!

Postby shadylane » Wed Oct 11, 2017 5:53 am

What ester is responsible for the sharp burning taste in a sugar wash?
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Re: !!! -> Need questions for an interview on esters ASAP!

Postby thecroweater » Wed Oct 11, 2017 6:14 am

what makes oats smooth, something is going on here, get a gain like rye and its super peppery and oats and it will smooth it or and other bill and straight oats are ultra smooth. Would love to know the actual reasons why grains produce this difference that is not apparent in the raw grain flavour.
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Re: !!! -> Need questions for an interview on esters ASAP!

Postby MDH » Wed Oct 11, 2017 11:40 am

OtisT wrote:The article says higher ABV can kill bacteria needed for esterification, and also says the ester creation process takes place over time in the barrel. 62% must not enough to kill all the bacteria (I hear some can live in space) No direct question here other that “hugh?” I am guessing that some bacteria do survive at 62% ABV and that the process is just slow.


The chemical reaction that results in esters involves oxygen, hydrogen and produces water and the respective ester. It works because fresh distillate and sometimes oak extract is acidic or rich in hydrogen ions. It isn't produced by bacteria metabolism.

Also, you didn't ask me, croweater, but I can definitely tell you why rye is peppery - it has to do with phenols present in the grain. They are called hydroxycinnamic acids and aromatic acids. These include complex ones (tannins) and acids like coumaric, syringic, caffeic acids. They're present in almost all grain and fruit, but some more than others. Longer growing seasons accumulate more of it, which is why northern harvest grains (from Canada such as Saskatchewan or northern BC) have a more intense profile. Bacteria will metabolize these hydroxycinnamic acids into simple phenols or phenyl esters in a mash environment, which are heavy, but volatile enough that they could make it into distillate if you were just using basic pot distillation. During aging they further develop into other compounds that give rye its signature flavors such as mint or medicinal quality.

Also should mention that these acids are responsible for Brett flavors as brettanomyces yeast eats coumaric acid and spits out two compounds which are responsible for that offputting barnyard character some people apparently like for some reason.
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Re: !!! -> Need questions for an interview on esters ASAP!

Postby JohnsMyName » Thu Oct 12, 2017 6:10 pm

This thread is great! Thanks for your words MDH. Can't wait to hear answers to the great questions above too! I'm especially interested in the backseat questions.
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Re: !!! -> Need questions for an interview on esters ASAP!

Postby OtisT » Fri Oct 13, 2017 9:26 am

MDH wrote:
OtisT wrote:The article says higher ABV can kill bacteria needed for esterification, and also says the ester creation process takes place over time in the barrel. 62% must not enough to kill all the bacteria (I hear some can live in space) No direct question here other that “hugh?” I am guessing that some bacteria do survive at 62% ABV and that the process is just slow.


The chemical reaction that results in esters involves oxygen, hydrogen and produces water and the respective ester. It works because fresh distillate and sometimes oak extract is acidic or rich in hydrogen ions. It isn't produced by bacteria metabolism.


Doh! Thanks, that makes sense. I should have known that ( I did know that ), and that's what I get for not rereading and thinking through my own question. Thanks for setting me straight. Otis. :-)
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Re: !!! -> Need questions for an interview on esters ASAP!

Postby Shine0n » Sat Oct 14, 2017 1:20 am

I have no questions but just wanted to thank MDH for his knowledge and passing it down.
You're a very intelligent man and I enjoy reading your posts.
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Re: !!! -> Need questions for an interview on esters ASAP!

Postby zapata » Sun Oct 15, 2017 2:49 am

These are all great questions. I'd end with whats next after esters? We need something new to nerd out on!
Yeast generated phenols?
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Re: !!! -> Need questions for an interview on esters ASAP!

Postby zapata » Sun Oct 15, 2017 2:55 am

OtisT wrote:How do you identify ester smells/tastes?

Did you see this chart I put in one of shineon's threads?
download/file.php?id=52466&mode=view
Not very nuanced, but I found it very informative.
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Re: !!! -> Need questions for an interview on esters ASAP!

Postby JohnsMyName » Mon Oct 16, 2017 9:18 am

Did you ever get any answers?
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Re: !!! -> Need questions for an interview on esters ASAP!

Postby Single Malt Yinzer » Mon Oct 16, 2017 4:47 pm

I sent him our questions. He's working on answers and we'll schedule the live interview when he's ready - maybe later this week, but it will be up to him. I will keep everyone updated once I hear something.
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Re: !!! -> Need questions for an interview on esters ASAP!

Postby Single Malt Yinzer » Wed Oct 18, 2017 4:50 pm

Let me preface this by saying that my opinions are from the standpoint of a microbiologist/biochemist. While I have over a decade of experience working directly with distilleries, my expertise lies more with the microbiology and biochemistry of fermentation (yeast and bacteria), rather than a chemical expert on ester biosynthesis.


What process causes the most esters to form? (Enzyme/Fischer/Other)
When looking at esters I consider which ones were produced by the yeast and bacteria in fermentation to begin with (often simple esters with fruity notes) and also what esters were formed from precursors (alcohols and carboxylic acids- ethyl alcohol plus acetic acid = ethyl ecetate, for example) during fermentation, distillation and barrel aging. Also, what do the simple esters become over time during barrel aging- do they stay the same, turn into complex esters (with more complex clove or spicey notes). I need to brush up on hard core ester chemistry and relevant literature. This is very complex and there doesn’t seem to be any simple answers.


In what stage do most esters form? (Ferment, Wash run, Low Wines, Spirit run, aging)
My guess is fermentation and aging. Our whiskies are currently aging, so every year we gain more data and learn more.


What process(es) creates the best esters for whiskey/rum?
Fermentation and aging are where it’s at. This would be dependent on several factors- yeast strain, presence or absence of bacterial contaminants, fermentation conditions (temp, duration, pH, mash recipe, etc), aging conditions (type of barrel- age of wood prior to making barrel, toasting, char level), entry proof, pH/acidity (drives ester reactions), how long in the barrel, etc. So very multi-factorial. This would vary for whiskey and rum.


How can one target specific esters? (As an example Redbreast’s rose/floral notes)
This is the billion dollar question. If you like certain notes from a particular product, then you can start with the mash recipe if you can get it. Along with the yeast strain and fermentation conditions, barrel and aging details as mentioned above. There are several different esters that produce floral notes, but most have 6+ carbons on the alcohol component and 9 carbons from the carboxylic acid. There are others such as esters derived from salicylic acid (a plant component), but it is uncertain exactly how these are formed.


Does wort clarity affect ester production, does it target specific ester production?
My guess is that any part of the fermentation process that can be changed could affect ester production, even if ever so slightly. This would also depend on the starting ingredients/grain bill, yeast strain, bacteria, etc as above.


For ester production, what process is better: Sour Mash or Muck?
This is debatable. We run a sweet mash process at our distillery and we get wonderful aromas. Our aging whiskies are also first class, so we know you can accomplish an exceptional ester profile without sour mash or muck. Having said that, either of those would contain organic acids (lactic, acetic, etc) that are precursors to esters. Also lower pH can drive ester production, so another thing to consider. If either sour mash or much contributed wild yeast or contaminating bacteria, that would be another way it would influence ester and other chemical production.


Has there been any research into putting tails in ferments?
We often recycle tails back to the beer well, but not fermentation (could be toxic to the yeast). We only make tails cuts on our pot still. Most larger distilleries, including us, use column stills, so tails are controlled by column temps and doubler conditions. Having longer (carbon) chain alcohols could influence production of more complex esters (hexyl-, benzyl-, or heptyl nonoate, for example).


For ester production, what would you consider to be a minimum ferment time? Maximum useful time?
This is debatable and would be highly dependent on the yeast strain and any contaminating bacteria, in addition to other factors like the mash bill.


Are there any ways to increase ester production in aging?
Age longer. Different barrel treatments (aged wood, toasting, char level). Position in the warehouse (temp, humidity). Barrel entry proof. pH and acidity of the distillate.


How does oxygen in the mash affect esters?
We know that oxygen can oxidize alcohols to form aldehydes and acetic acid. Acetic acid is a precursor to ethyl acetate, so that is one small example of how oxidation could influence ester production. There are likely other reactions that could similarly affect ester production. We also know that oxidation drives production of chemicals like vanillin, which is a positive influence to aged bourbon.


How does pitching rate affect yeast?
Depends on the strain, the reproductive capabilities, fermentation temperature and many other factors.


What yeast produce the most esters?
In beer production, ale yeast produce more esters than lager yeast for example, but they are generally fermented at highly varying temperature. But that isn’t the only way esters get into the beer. One must also consider the precursors produced by yeast and bacteria (organic acids).


Is there a way to encourage yeast to produce esters?
My belief is to start with a simple process that can be repeated and if it works it takes less effort to maintain great consistency. There are all kinds of different opinions and methods for “improving” esters, but at the end of the day if you do something (sweet mash vs sour mash, this yeast vs that yeast, level of bacterial contamination, grain bill, etc, etc,) to make a distillate, if the end result is favorable and has a distinguishable bouquet, then you don’t even need to know anything about ester chemistry to be successful. Many distillers that talk about ester profiles, may just be referring to aromatic qualities in general without elucidating if specific notes are from esters, alcohols, aldehydes, acids, oils, etc.


Does clarity of the wort affect esters?
See above.


How does floculation affect ester production?
This probably matters more in beer production, because grain based alcohols have such high solids in fermentation the yeast don’t settle out like they do in a clear wort. Rum production would be more like beer (less solid and a clear mash), but I don’t know how flocculation would affect ester production.


How does open/closed fermenting affect esters?
Open top could allow for more bacteria and wild yeast contamination. Closed top may cause backpressure or additional temperatures, so I’d say there are good and bad with each type. Closed top would also likely be more “anaerobic” due to less ability to vent CO2. This could affect oxidative reactions and is known to affect yeast metabolism as it relates to unsaturated fatty acid biosynthesis and sterol production. Not sure how that would fit in with ester production, but the point is the level of oxygen can affect yeast metabolism, which is bound to affect ester or ester precursor production.


What are we missing with esters?
I would like to know more about the following:

Examples of simple esters (fruity) and how complex esters (floral, spicy, clove, etc) are formed and examples for each. Also what drives these reactions in fermentation, distillation, and barrel aging.

Examples of esters that can be tasted at levels below detection.


Does breaking down proteins to amino acids (the protein rest) in unmalted grains increase ester
production?
It sure could as liberated amino acids lead to all kinds of different chemical reactions and serve as precursors to many metabolic byproducts. We cook our small grains (wheat, rye and malted barley) at lower temps than corn to reduce breaking down proteins. We are mainly concerned about liberating arginine, a precursor to ethyl carbamate (a carcinogen).


Does Fischer esterification require a second type of acid or is one type of acid enough? (example: an
alcohol plus a lactic acid plus another lactic acid work, or would it require a different acid like
sulfuric?)
Sulfuric can serve as a co-factor and drives the reaction, but I don’t think it incorporates with an alcohol like an organic acid (acetic, etc). This gets a little out of my area of expertise, although I could read up on it.


What’s the best way to reduce ester production? (for neutrals)
That is hard to say.


Other questions:
What order do you see contributors to flavor profiles?
Grain bill and grain quality, barrel quality and aging, yeast strain, method of fermentation, method of cooking the grains (from most likely contributor to least).


Aside from esters, what do do you think homedistillers should focus on for flavor development?
Running a process that is consistent and can be repeated while producing an excellent spirit. I think errors or just plain bad ideas are what lead to bad juice. If you stick to tradition, develop a nice prototype and change it slightly from there by making incremental changes you can formulate a unique process and great juice.


Processes, materials, etc.

What’s the hardest thing to master in developing a great flavor?
Consistency between batches.


How to keep Muck pits from become ammonia?
This would depend on several factors (muck chemistry, microbes present, oxygen potential, etc).


For conversion, is Alpha required or can it be done completely by Beta?
My understanding is that you need alpha. After all it is alpha 1,4 and 1,6 linkages you are trying to break. Beta can help reduce viscosity, but nothing that alpha won’t do.


What books you would recommend for aspiring distillers?
All of the articles I sent to you that I wrote. As well as the old Seagrams books and manuscripts. Also come to one of our training sessions and we’ll show you how it’s done.
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Re: !!! -> Need questions for an interview on esters ASAP!

Postby Single Malt Yinzer » Wed Oct 18, 2017 4:55 pm

Der Wo:
1. The glue smell of Bourbon is obviously ethyl acetate. Produced by vinegar bacteria. Open fermentation seems to be the reason.
There are other ways acetic acid is produced rather than by bacteria, like the yeast. It isn’t always vinegar bacteria (Acetobacter, for example), its often lactic acid bacteria like heterofermentative Lactobacillus and related species. Further, ethyl alcohol can be oxidized to form acetaldehyde and acetic acid. Open fermentation it would seem would lend to things being aerobic enough for Acetobacter and related bacteria. However, we more often find these bacteria in yeast prop tanks (aerated) and beer wells (indicates it is more aerobic than fermentation), and less often from fermentation.

But why even young Malt Whiskies doesn't have it?
Maybe the malt overpowers the ethyl acetate?

They also are fermented open normally. Is the key the fores cut of pot distillation vs no fores cut in continuous
distillation.
There is probably something to that, for example, if you left in higher alcohols this could lead to longer chain esters, which lend floral and complex scents.

Or are there other causes like the warmer climate in Kentucky than in Scotland?
Warmer climate could lend to esterification reactions, but it would depend on many other factors.

2. How is backset of sour mash Whiskey stored? Open, sterile? And how long until they add it to the mash.
Typically backset is stored only for a short time before it is added as part of the cook water, I would say within a day of making it. It would also likely be kept very hot (>150F) until used. We do not use backset at our distillery (sweet mash), but get great ester production.

3. What role plays the yeast selection, what bacteria, what the circumstances (temperature, fermentation duration for example).
See above.

6. Are there Bourbon distilleries using acids (besides backset) to rise esterification? Which acids? Sulphuric acid?
Lowering the pH can drive ester reactions (like by adding sulfuric). Normally when I think of acids in ester formation, I am thinking about the carboxylic acid that condenses with the alcohol to form the ester. I don’t know of too many distilleries adding sulfuric to the distillate. It wouldn’t classify as a bourbon if you did that. However, many distilleries will test acidity of their distillate.
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Re: !!! -> Need questions for an interview on esters ASAP!

Postby Single Malt Yinzer » Wed Oct 18, 2017 5:00 pm

OtisT:
First, please tell him “Thank You”
You are welcome!


Question (area) 1:

I have begun to follow and try the various discussions on HD as to when, where, and how to use
backset to create esters. My first question would be to ask his opinion on which of these methods may
be most promising (or not) at producing more/different esters, and why? His article covers bacterial
infections well, so this is excluded here.
• Backset added pre-fermentation
• Backset added direct to low wines prior to spirit run. (follow-up. Does he think any esterification is
taking place because of high heat during the boil?)
• Backset mixed with feints alcohols. Let age (or not) and add to low wines
• Backset added to your cuts
I think most of these were answered above (to the best of my current capability).

Q2:
If mixing backset directly with alcohol (not ferment) for the purpose of creating esters works:
• What kind of ratios/concentrations/measures are needed to foster esterification? (ex. Should we need
to adjust PH, dilute alcohol, etc.)
Typically distilleries will use an amount of backset equal to 20-30% of their water added to cook.

• Should we be amending this chemical mix to foster esterification?
• Time/Temp for reaction to complete? (varies by method?)
• What alcohols would be most promising for esterification and why? Either by alcohol name or maybe
simply considering fore shots, heads, hearts, tails? Does it matter?
Q3:
The article says higher ABV can kill bacteria needed for esterification, and also says the ester creation
process takes place over time in the barrel. 62% must not enough to kill all the bacteria (I hear some
can live in space) No direct question here other that “hugh?” I am guessing that some bacteria do
survive at 62% ABV and that the process is just slow.
I was referring to higher ABV’s in fermentation that can inhibit or kill bacteria that produce esters. This isn’t a catch all as there are many different possible bacteria (we have over 5,000 just in our collection) that have a range of temp, alcohol, sugar and other tolerances and produce varying amounts of different esters. Throw in the yeast strain and possibly wild yeast and this gets complicated real quick.

Q4:
Personal Preference. What specific esters would be in your “perfect” Bourbon?
Its not just about esters, but I like a bourbon with the basic vanilla, caramel and nuttiness, but also with floral and complex notes of spice (clove, tobacco, etc). I like all kinds of different bourbons, so one flavor profile doesn’t cut it for me.


Related, but off subject Question:
How do you identify ester smells/tastes?
Sniffing and tasting the product and matching up aromas to a flavor chart with esters, followed by analytical testing (GC-MS, MALDI, etc) to figure out which esters are detectable, etc.


Please briefly describe your process of isolating and
identifying these wonderful smells/tastes. Underlying question is how do we learn to do this?
Start by making something and sorting out the flavors, then make small changes and see how it affected the base spirit. Its all about trial and error.
Is there a
book, specific reference chart, site/blog that he thinks describes this well? [This is extremely difficult
for me. I am great and comparing/contrasting, but in isolation naming a smell is not my thing.]
All my the papers I passed along. There are good on-line resources for esters and ester production, but I have yet to find a cohesive resource for esters and distilled spirits. This line of questioning has prompted me to write a white paper, so watch out for that.

Extra Credit Question:
Teach us a new ester trick we can try. Anything he thinks is cool with esters that an enthusiast may find
to cool. Maybe a yeast/recipe/process that makes a product that tastes like a peach,

There are all kinds of ideas here. First, we have several thousand yeast strains and species that have never been used (at least in recorded history) for making bourbon, yet they are good candidates and some with very unique and novel ester (and other chemical) production. We want to use these strains to make a very unique product. Also we are looking at incorporating very specific bacteria into the process out of our collection of several thousand isolated from distilleries. Given that any part of the process can be varied, it lends to thousands of different permutations for creating unique products.
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Re: !!! -> Need questions for an interview on esters ASAP!

Postby Single Malt Yinzer » Wed Oct 18, 2017 5:03 pm

Articles he wrote that he sent me:
AS_Issue012_SugarUtilization.pdf
(676.43 KiB) Downloaded 9 times

ArtisanSpirit_Issue011_MicrobialContamination.pdf
(377.37 KiB) Downloaded 8 times


ArtisanSpirit_Issue009_YeastStrains.pdf
(677.03 KiB) Downloaded 21 times
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Re: !!! -> Need questions for an interview on esters ASAP!

Postby Single Malt Yinzer » Wed Oct 18, 2017 5:06 pm

For me, the best part:
This line of questioning has prompted me to write a white paper, so watch out for that.


It makes me happy to see us inspire him. Yinz are awesome. Thanks for asking questions. For those that didn't get their questions answered I will do so during the phone interview. OtisT - it should be next week sometime.
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Re: !!! -> Need questions for an interview on esters ASAP!

Postby RedwoodHillBilly » Thu Oct 19, 2017 7:01 am

SMY, good read, thanks. He did dodge Otis's Q1 and Q2. That is an area that I'm starting to experiment with. I think that there is some interesting data to be gained, but good design of experiments are going to very important. My guess as to why he dodged the Qs is that he doesn't have any direct experience, as they don't seem to use any of those processes.
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Re: !!! -> Need questions for an interview on esters ASAP!

Postby OtisT » Thu Oct 19, 2017 8:20 am

Single Malt Yinzer wrote:OtisT - it should be next week sometime.


Thanks. I’ll be reading his articles, responses, and will be ready to go when the time comes. :-)
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Re: !!! -> Need questions for an interview on esters ASAP!

Postby ShineonCrazyDiamond » Thu Oct 19, 2017 3:19 pm

I would like some more clarification on this from someone smarter than me on the subject...

We cook our small grains (wheat, rye and malted barley) at lower temps than corn to reduce breaking down proteins. We are mainly concerned about liberating arginine, a precursor to ethyl carbamate (a carcinogen).


So there are lots of us here that boil corn and grains in all (wheat, rye, malted barley), and then add enzymes for conversion. This pastuerizes the grains, and is easier. So this could be creating, or liberating, carcinogens, in the mash?
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Re: !!! -> Need questions for an interview on esters ASAP!

Postby RedwoodHillBilly » Thu Oct 19, 2017 3:48 pm

ShineonCrazyDiamond wrote:I would like some more clarification on this from someone smarter than me on the subject...

We cook our small grains (wheat, rye and malted barley) at lower temps than corn to reduce breaking down proteins. We are mainly concerned about liberating arginine, a precursor to ethyl carbamate (a carcinogen).


So there are lots of us here that boil corn and grains in all (wheat, rye, malted barley), and then add enzymes for conversion. This pastuerizes the grains, and is easier. So this could be creating, or liberating, carcinogens, in the mash?


I'd be curious as well. When using unmalted grains (except for corn) I add them at 170°F or so on the way down. What temps does he add/cook unmalted grains at? Is there a range that arginine production is reduced vs gelatinization temperatures?
John Barleycorn must die.
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The huntsman he can't hunt the fox, nor so loudly to blow his horn
and the tinker he can't mend kettle nor pots without a little barleycorn."
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Re: !!! -> Need questions for an interview on esters ASAP!

Postby Single Malt Yinzer » Thu Oct 19, 2017 3:58 pm

I'm not smarter than you but this is what I know:
In short it's a concern, but that it's not quite defined as to how much of a concern. https://en.wikipedia.org/wiki/Ethyl_carbamate#Hazards

It's a problem for commercial distillers that want to export to the EU. They require testing for it and do not allow any in spirits. Some commercial grain are specifically bred to have zero precursors. In the EU most/all commercial grains are like that.


http://onlinelibrary.wiley.com/doi/10.1 ... .12084/pdf
https://www.fda.gov/downloads/food/food ... 119802.pdf
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Re: !!! -> Need questions for an interview on esters ASAP!

Postby RedwoodHillBilly » Thu Oct 19, 2017 4:13 pm

Single Malt Yinzer wrote:I'm not smarter than you but this is what I know:
In short it's a concern, but that it's not quite defined as to how much of a concern. https://en.wikipedia.org/wiki/Ethyl_carbamate#Hazards

It's a problem for commercial distillers that want to export to the EU. They require testing for it and do not allow any in spirits. Some commercial grain are specifically bred to have zero precursors. In the EU most/all commercial grains are like that.


http://onlinelibrary.wiley.com/doi/10.1 ... .12084/pdf
https://www.fda.gov/downloads/food/food ... 119802.pdf


Thanks for the links. Everybody is smarter than me, I hope. I never want to be the smartest guy in the room, if so I don't learn much.
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The huntsman he can't hunt the fox, nor so loudly to blow his horn
and the tinker he can't mend kettle nor pots without a little barleycorn."
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Re: !!! -> Need questions for an interview on esters ASAP!

Postby yakattack » Fri Oct 20, 2017 10:01 am

Just subbing in
HDNB wrote: The trick here is to learn what leads to a stalled mash....and quit doing that.
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Re: !!! -> Need questions for an interview on esters ASAP!

Postby Single Malt Yinzer » Thu Nov 02, 2017 6:46 am

Interview complete - I need to figure out how to post it once I get it converted to MP3. It was good!
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Re: !!! -> Need questions for an interview on esters ASAP!

Postby OtisT » Thu Nov 02, 2017 4:41 pm

Single Malt Yinzer wrote:Interview complete - I need to figure out how to post it once I get it converted to MP3. It was good!


Thanks again for doing this. Looking forward to it.
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