235 – Bourbon Chemistry with Dr. Tom Collins

Are you ready to geek out? Like super bourbon geek out? Dr. Tom Collins has dedicated part of his career to the details of different spirits and wine. His studies looking at the chemical composition of bourbon as well as the chemical influence from barrels is what intrigued us. We examine, at a scientific level, what char levels create different compounds and reactions, how entry proof affects these compounds, and how bourbon and rye are different in their molecular makeup. Like I said, get ready to geek out!

Show Notes:

  • New EU Tariffs: https://www.latimes.com/food/story/2020-01-04/trump-wine-tariffs and https://qz.com/1779258/a-us-wine-tariff-on-the-eu-isnt-great-for-california/
  • Scotland ankle monitoring: https://www.thescottishsun.co.uk/news/5128975/scottish-criminals-alcohol-ankle-tags/
  • This week’s Above the Char with Fred Minnick talks about turning your hobby into a career.
  • What is viticulture and enology?
  • How did you choose this profession?
  • Tell us about your research.
  • What compounds are you looking for from toasted barrels?
  • Are there times where a toasted barrel provides a certain flavor profile in the lab, but not in the real world?
  • Is it hard to get consistency from the barrel?
  • What was the outcome of your research?
  • How do you get a buttery taste out of a barrel?
  • Can you tell different whiskies apart chemically?
  • What are the different compounds in rye vs. bourbon?
  • Do bourbons have more differentiation compounds than ryes?
  • How does each compound contribute to the bourbon?
  • What kind of budget did you get to buy the bottles for research?
  • Where do the fruity notes come from in bourbon?
  • What are your thoughts on barrel entry proof?
  • Do you think you could look at dusty bourbons from the 60’s or 70’s and see differences compared today?
  • What’s a big takeaway from your research?
  • What happens when a whiskey is aged in a wine cask?


Yeah, I’m excited about today you sent me like beforehand, here’s some info, so we don’t look stupid. And then I started reading I’m like, well if I’m gonna look stupid

What’s up everybody it is Episode 235 of bourbon pursuit. And this week we are back in action, yet again talking about bourbon. But before we do that we do have some news to cover. Now, we already know that the trade war, it’s going pretty strong and bourbon has been hit, and there’s no telling if that is ever going to end. But now, there’s a new target insight as part of a retaliation effort and we’re looking at wine as sort of say more specifically European wine and other kind of European whiskeys. So there’s currently a looming trade tariffs up to 100% that would affect all European Union countries, selling wine and other spirits to the United States. Now wine in general is imported as a $20 billion a year industry here in the States. And this follows already an existing round of 25% tariffs that have been levied back in October against Spain, France, Germany and the United Kingdom. American wine drinkers would be faced with fewer wines coming to America from the EU, especially those made by small independent producers. And you can expect higher prices on those bottles that do make it in for those that make a livelihood in the wine trade. The mood is less than stellar importers, distributors, wine shop owners, Somalis and grocery store wine buyers said they fear that would have to impose salary or staffing cuts as a result of dramatically reduced profit margins. Now you might think that this would be good for domestic wine producers like those in California that make up 95% of the US wine market. However, the wine Institute has spoken out against the terrorists, arguing that the EU could just as easily turn around and target us winds in a tit for tat trade war, as much as California vendors want to serve up their wine for domestic consumers. Europe is still their most important export market, bringing in around 460 $9 million in 2018. And you can find the links to these two articles from the la times in QC calm with the link in our show notes. The Tennessee ABC has issued a cease and desist orders from out of state businesses who have been doing direct to consumer shipments of alcohol. Now we talked about shipping alcohol all the time on the podcast, and this one is kind of rolling things back in a negative way. As a quote, wine is the only alcoholic beverage that can be legally shipped direct to consumers in Tennessee, and it requires a winery direct shippers license issued by the Commission, and this is coming from the Tennessee ABC director Russell Thomas. The Tennessee ABC recently discovered the illegal shipments after analyzing common carrier reports compiled by the Tennessee Department of Revenue. It requires common carriers to file alcohol delivery ports. To the Department of Revenue each month, and it also requires that any business that sells and ships wine director Tennessee has to be licensed as well. In other news, the Scottish Government is trying to tackle booze related criminals, and they have given the green light to remote alcohol monitoring in sobriety tags after awarding a multimillion pound security firm contract. The anti booze angle tags can detect if you’ve consumed alcohol by monitoring the sweat every 30 minutes from your pores. But ministers are still in talks about handling Scottish courts the power to force these criminals whose convictions are linked to alcohol to actually where these tax if this goes ahead, then they can be forced to go alcohol free for a month to tackle the drinking problem which contributed to their crimes. You can find the link to the Scottish son within our show notes. Alright, so you ready to geek out and I mean, like super bourbon geek out. I heard about our guests today Tom Collins, after I learned he gave In Depth talk at tails. It intrigued me to know more about the science behind bourbon. Tom has dedicated part of his career to the details of alcohol in for us, it’s looking at the chemical composition of bourbon, as well as the chemical influence from the barrels as well. We examine at a scientific level, what certain char levels create how entry proof affects it in how bourbon and rye are different from their molecular makeup. Like I said, Get ready to geek out. But now let’s go ahead and take a break. We’re gonna hear from Joe over barrell bourbon, and then you’ve got Fred minich with above the jar.

It’s joe from barrell bourbon. I know I talked a lot about blending here, but we also have a national single barrel program, ask you a local retailer or bourbon club about selecting your own private barrel.

I’m Fred MiniK. And this is above the char this week’s idea comes from Kyle man on Twitter or at bourbon numbers on January 2, He wrote me and said, Does making a career out of your hobby ever diminish the fun or actually deepen the experience? Do you have a hobby you would not go pro for that reason? Thanks. That’s a great question calm, and I actually do have quite a bit of experience with this. See, I initially started my career as a sports writer. Well, professionally I did. So my career starts as like an ag journalist where I was covering crops and cattle futures and things like that. But I always wanted to be a sports writer, because I was a huge sports junkie. I get into sports, you know, in high school, I start writing about, you know, local football games, track baseball. I would also write about anything that anybody would let me write about to be honest with you. But I get to college and I start writing about sports. And I take a job with the daily Oklahoman, I’m on the sports desk there. And I’m writing the headlines for the daily Oklahoman and I start interviewing athletes and coaches and there was one thing that was Pretty common, it did not matter, the level or the sport. Coaches did not treat reporters with the same respect that they did. colleagues or their players or parents even in the players kind of follow the leadership of their coaches. And for the most part, reporters get treated like crap in the sports business. And you don’t have to look any further than a Bill Parcells or Bill Belichick. Press conference to see what I’m talking about. They often come with a very much a disdain toward reporters, and I was coming at it from a fan’s perspective. And I didn’t necessarily like the way that sports the kind of Avenue I would have to go down in order to continue a career in sports. Because as I was covering them, I felt my I felt the fan being ripped away from me. I didn’t enjoy that. I want to be honest with you. enjoyed being a fan far more than I did covering sports. Now fast forward to my bourbon career, I start writing about bourbon in 2006 and 2007 and get really serious about it between 2010 and 2012. And I kind of started in a period in which people weren’t really writing about bourbon on a professional level. You did have some bloggers and you had a couple magazine writers, but there was not a lot of us. And to this day, there aren’t that many professional whiskey writers. But back then there were there were not the proliferation of blogs, social media wasn’t around. And distillers were just happy to get attention from anybody really, in the consumer base was, we’re all about, you know, people who would crack open this kind of mythical bourbon egg and shine the light upon some of the secrecy and those that was kind of what I was doing. And so I found myself in a where both of the consumer base and the distiller base were very excited to see any kind of writing I was doing. And while that has certainly change my passion for bourbon has not the one thing that has changed in bourbon and it’s nothing like it wasn’t sports, you you tend to have a lot of people who enter this space and want to make a career out of it or they want to cash in on bourbon while it’s big. And those people tend to go away because they don’t have the passion for American whiskey like many of us do, and they just see American whiskey as as another check. And I think right now we’re seeing a lot of those kinds of people come and go. And those who have the passion, those who want to see this, you know, through the end and enjoy it for the rest of our lifetime. You’re going to see us around for a long Long time, even when whiskies not popular anymore, and that’s this week’s above the char Hey, if you’re interested in getting a career in American whiskey, there’s all kinds of avenues open for it. You can even find some places to go to school to learn more about it. I think Kenny’s got a few ideas

he’d like to share with you.

And that’s this week’s above the char hit me up on Twitter or Instagram, if you ever want to connect. Until next week, cheers.

Welcome back to another episode of bourbon pursuit the official podcast of bourbon, Kinney and Ryan here tonight we are well during the day. I don’t know me I’d be driving right now but we’re recording this at night and in this is going to be something that like, I’m gonna I’m going to really, really enjoy because especially anybody out there that has had any background in science or chemistry. We’re about to geek out here.

Yes, yeah. I think the light Last time we really kicked out was when we were talking Easton, like with Pat heist and then from wilderness trail we kind of went well I did anyways like, went down this rabbit hole of like, all these crazy sports talk and all this stuff that’s way over a lot of people’s head but yeah, I’m excited about today you sent me like beforehand, here’s some info, so we don’t look stupid. And then I started reading I’m like, Well, if I’m going to look stupid

we’re talking about the very beginning our guests today sent over some some abstracts or some some scientific papers that he had helped publish and stuff like that. And, and one of them I’ll just kind of read the title was called profiling a non volatiles and whiskey using ultra high pressure liquid chromatography quadruple the time of flight mass spectrometry. That was the title and like, like

Mind blown here, right. I started reading through it and have a horticulture degree with terman. Like, I remember having to take organic chemistry and like barely passed it. And this reminded me of a lot of it. So this is brand new, like bad memories of like failing at life in school. And so Tom will be easy on us.

Yeah, absolutely. So let’s go ahead and introduce our guest today. So today on the show, we have Dr. Thomas Collins. He is the or is an assistant professor at Washington State University in the Viticulture and Enology program at Washington State. So Tom Welcome to the show.

Oh, well. Hi, thanks for Thanks for the invite. I’m I’m looking forward to this conversation. This should be fun.

Absolutely. Did I did I did I stumble on your the program that you’re in there?

Or did I go I think I got it right. Then I did Viticulture and

Enology. Alright cool. I didn’t put her to bed. So for for people that want to know more about even what that is explained even what Viticulture and Enology is to our our listeners out there.

So Vedic Vedic culture is the science of grape growing virus. Is the species for grapes. So viticulture is just the study of grape growing. And then analogy is the study of winemaking. So my background is I’m a chemist and I do work in aroma and flavor chemistry of grapes, wines and distilled spirits. Nice.

Yes. So how did you choose that path? I mean, that would mean if I had a chemistry degree, that any film to choose I would probably it, but how would How did you get involved with that?

Well, I think you’re on the right track there. If you’re going to do this sort of thing. It’s important to study something you’re going to enjoy studying, right? So there’s lots of areas of science you can go into, and some of them I wonder how people get involved. But I think studying grapes and Wine and Spirits seems like an area that would be enjoyable. You’re going to have samples to work with and samples to all kinds of sensory evaluation. Right? Yeah, absolutely offer research. All in the name of science.

I’m surprised you don’t have a plaque behind you that says that or something like that. Just a banner that says just just for science here.

Yeah, well, the the license plate holder on my car says Life is too short to make bad wine. So pretty nice.

So I guess kind of talk about, because I know you do a lot of stuff with wine now, but I know that you know, we had originally reached out to you because I saw it. You had done a presentation at Tales of the cocktails A few years ago, and was really I said, like, there’s got to be somebody out there that really knows like the chemistry behind bourbon. And so you had you had kind of been doing that. So kind of talk about your research over the years and kind of what you’ve been focused on in that category.

So I guess the way the how I ended up here was I worked for a big winery wine company in California, and I work with them while I was doing my PhD at University of California Davis. And, and the focus of my research at that time was on oak aroma and flavor chemistry because the winery I worked for the cooperage. So they had a company that was making barrels for them. And the focus was really trying to understand how the coopering or barrel making process affects the outcome of the barrel, what what the chemistry of the barrel looks like. And then ultimately, the chemistry of the wine that’s aged in those barrels. And so that was my PhD project was really just trying to understand how what happens in the cooperage affects what happens to the barrel and then what happens to the wind start in it. The next step is to look at are the next one of the next steps in my research development was alright, so that’s what happens when you put wine in a barrel and it’s 15% alcohol. What happens if you then look at a different beverage a different product, what happens is we put whiskey in that barrel instead, now we’re talking instead of 15% alcohol, we’re at 60 65%. Alcohol, you’re going to extract different things, the barrels are made in a different way. So it just was sort of a logical, logical extension to the research I had already done. And also gets me into the working in distilled spirits, you know, an area that I enjoy personally. And here’s an opportunity to learn a little bit more about how things are different with spirits compared to wine.

Yeah, absolutely. I mean, that is cool. And so I guess let’s, let’s kind of go into that topic a little bit. Right. I mean, I think the first one that you kind of mentioned was, was the oak and the wood and stuff like that kind of kind of talk about some of your research that you did in regards of really what the because I think there was one. One paper you had also written called targeted volatile composition of awkward samples taken during toasting, edit. mercial cooperage. So kind of kind of let’s talk about, really, what, what the goal, or the thesis of this was, and then the results and really where you came out of this?

Well, from a, from a practical standpoint, the question we were trying to answer with the initial research, when I still work with the winery was, the company owns this cooperage. So it gives us an opportunity as a company to have barrels made exactly the way we would like them to be made rather than buying barrels that someone else has made and decided how they wanted to do the toasting. This was an opportunity for winemakers to talk directly to the Cooper’s and say, This is what I’m looking for in a barrel and have the Cooper’s make them for that. It sounds like a great prospect. But it turns out, it’s hard. You need a translator between what winemakers say they’re looking for, and what Cooper’s can actually do. So if the winemaker says I want a certain kind of tannin or I want a certain aroma, flavor profile. There’s that there has to be some translation for the Cooper to understand what they’re looking for and how winemakers speak sort of translates into something that they can do in the cooperage to achieve that goal. And so that’s where this the genesis for this research project was really just trying to understand. If winemakers are looking for a certain thing, what are the Cooper’s have to do to achieve that? And that morphed into really just trying to understand how does the whole process of toasting barrels work? And what are the key factors in terms of where the wood originates from, how it seasoned, how you’re going to toast it to get to a certain aroma and flavor profiles that the winemakers might look for. And so that’s where you get these studies where we’re looking at volatile profiles changing during the testing process because we’re trying to understand what components are being generated as you heat the barrel as you toasted, and how they changed throughout throughout the toasting process. So, so it turns out many of the things that we associated with toasted out in terms of the aromas of vanilla and clove and the spicy aroma is sort of the things that we’re looking for from our barrels. Most of those are produced during the testing process. They’re not present in the untoasted what

what are some of the things that you’re that you’re looking for?

So the actual compounds so yeah, yeah, getting it on us. Yeah. What about on that road? Well, the first one is vanderlin which is not surprising the one that smells like vanilla. But we’re also looking at things like huge and all an ISO huge and all which have clove type aromas. Huge and also the primary compound in in clothes. We’re looking at firfer awls, which comes degradation of sugars during the toasting process. So, the cellulose and Hemi cellulose that compose the structure of the wood in part, when those when that’s heated, you get thermal breakdown that results in the formation of firfer all kinds of compounds that give you these toasty aromas. And other structural polymer in wood is lignin. And when you when you break that down by heating it, you get things like we get vanel in for one you get quiet call and for methyl glycol, which are related, which are the whiskey lacked are related to the whiskey lactones through the kinds of aromas that give you spicy or medicinal characters, depending on their concentrations in which ones you get. So there are a number. I mean, we looked at about a dozen different compounds and looked at how they’re produced throughout the toasting process. So we put thermal couples into the staves as the bear before barrels were toasted. So we could measure the temperature of the wood throughout the process. And then we took samples at regular intervals during the process, and took that back to the lab for the analysis. And so while the barrels are being tested, we’re monitoring the temperature, we’re collecting samples, the wood, and then we can do the analysis to figure out how things changed throughout the testing process. These compounds aren’t all produced at the same time at the same rate. So some of them are, some of them take more heat to generate, and so they tend to develop later in the testing process. Some things are produced very quickly. But if you have too much heat, then they get degraded, broken down into other compounds, or they just volatilize and disappear. And so depending on what the winemakers looking for, you might want to toast the barrel for a longer period of longer period of time or a shorter period of time. You might do a high temperature short time toasting to emphasize things that are produced quickly. We might do a slower low heat, toasting protocol to produce things that take more heat to generate. And so by doing this kind of study, we could start to understand how to tailor the toasting process at the cooperage to get the specific aroma compounds that the winemakers were looking for.

Interesting. Yeah. So with the, how do you control I guess the variables, you know, because you have wood, which is a living thing, I’m just thinking of like turf research and like, you kind of have like a lot of uncontrollable variables because you are dealing with a living thing or was living in so how is Are there times that like, you know, you have like, like you said, we’re toasting the exactly the same with the exact same type of wood and it doesn’t translate like it did in the lab, you know, out in the real world.

Right? Well, and you really kind of hit the nail on the head, nail on the head in terms of the problem with the toasting process generally is there’s not a lot of control. In terms of how that happens, so the Cooper’s all have a protocol, they’re supposed to use this many fires. And you’re supposed to be on each fire for this amount of time. But one of the things we saw in this process is that there’s a lot of variability just in how the how the individual Cooper’s manage their fires. And so at this particular cooperage, there were two different Cooper’s that did the toasting, and they didn’t manage their fires quite the same. And their barrels were different, even though they’re following the same protocol, the same number of fires for the same amount of time. Getting the intensity, that fire to be consistent is one of the things that you have to do well to get a consistent outcome. And that’s that that’s fairly difficult to do, and some are who’s really on top of that can do a better job. But if the two if the two Cooper’s are not doing it quite the same, then you end up with barrels that look different. We could tell from the chemical analysis which Cooper made which barrels

really saying it just it just like with whiskey, you know, it’s like you do single barrel pics and you have sister barrels on the same exact row like honey barrels that just tastes like significantly different than one that’s like right next to it. You’re I wonder if those variables in the toasting even though they’re theoretically at the same char whatever, you know protocol that like you said there’s so many different variables that it right hard to like

pin that down. Yes, that’s exactly right and we and we saw the same thing in you see the same thing in winemaking. If you taste wine from 20 different barrels that are all made, same day, same cooperage, same wood, same forest, you have all those variables controlled, you still see variability in the outcome, and it’s because to a great extent it’s because of this variation in the testing process that it’s really hard to get that well controlled and and most Cooper urges don’t necessarily have a lot of instrumentation that says this is what the temperature is it would at this point there, it’s not. It’s not easy to put that kind of instrumentation in place. And most of them don’t have it. And they’re relying on the experience of the Cooper to come up with something that’s consistent. But I was it, it is a really difficult job to get that level of consistency day in and day out. I mean, we looked for one of the things we looked at is, over a four day period, how consistent were the barrels from one day to the next to the next to the next. And there there were definitely good days and bad days in terms of efficiency.

I’m kind of looking at some of the data here and you have you have some graphs that basically show the the the type of oak, the the type of toast, and then you have, like the level of vanderlin in regards of like what degree Celsius was the I’m assuming it was either the temperature or was the word at that time. So you can kind of really, you can’t actually calculate what’s at what temperature you’re trying to pull out the most of that particular compound.

Right? So so we look, again, we looked at about a dozen different compounds. And we measure the temperature throughout the process. And, and so we could start to say, when we get to this kind of temperature, we’re going to see formation of these compounds. And as it progresses, certain compounds like glycol, for example, the longer you heat it, the hotter it gets, the more glycol you get. But things like valin, there’s some there and the untoasted would, it gets produced fairly early in the process, but as you continue to heat the barrel, it drops off, it’s being converted into something else, or it’s just escaping. And so the goal of that was really to try and understand what temperature protocols you want to follow if you want to emphasize valen for example, rather than quiet costs, so if you want something that has more of those values, characters, how would you achieve that. Whereas if you want something that’s toasty smoky and has a lot of quiet call, you just keep toasting it, the harder you go that the more of it you get. So it’s the it those those particular plots are really critical to trying to work with the Cooper’s to understand what they needed to do to make specific profiles.

So what is the what’s the outcome here? I kind of of what you were trying to get or what was like the, the general data like what did it really say to you?

Well, so I guess the the main, the most important takeaway message from that whole study was, there’s a lot of variability in this process. And until Cooper’s really focus on getting consistent testing protocol protocols, getting that part of the process down all the discussion that we have in the wine industry about the upcoming from French for us, whether it’s white, green, oak, or Tiger Green oak or comes from this forest versus that forest, all of that stuff really doesn’t matter if the Cooper doesn’t have a way to toast the barrels consistently. So what we saw was the variability in the toasting process, sort of trumped everything else. Because until you could get that more consistent, you couldn’t see differences between tight grain and open grain, you couldn’t see differences between this forest and that, it was really more about how the barrels were toasted. So that was the first thing was the cooperage really needed to focus more on getting the Cooper’s to be consistent in toasting. The second thing was, if you can do that, then you have the possibility of making barrels that have specific flavor profiles by by adjusting how you do the toasting, to focus on baneling or to focus on glad calls. Those these things all have distinct curves for when they’re produced and when they’re degraded. And so you can start to adjust how you make the barrels to Focus on one flavor profile over another. So that was an important key. And then the other thing that came out of the overall process was as wine company, we knew a whole lot more about how to assess barrels, how to make decisions about the composition of barrels, and how that might interact with the wine that we were trying to make. And so we could give the winemakers a lot of information about barrel selection that I think allowed them to do some more interesting things with their barrels than they would have been otherwise. It’s it’s always good to have good information about the tools that you’re using. And this this study did a good job of helping the winemakers better understand the contribution of oak in their in their wine profiles.

There’s Cooper juice out there that not all of them toast their barrels right. So I guess this this is also showing that Yeah, there is scientific research and study here. That You can figure out that you can pour, pull more those types of compounds that you want by toasting it as well.

Yep. And I think just to jump ahead a little bit, I think there may be some information from this toasting study that could be beneficial for distilleries that are starting to move are interested in moving into these barrels that are toasted and then charred. Because you’re you’re going to use charred barrels generally speaking for bourbon but there there is a move at least in part towards doing some toasting the barrel first before you before you chart and and I think the potential benefit there is you below the Charlie or you’re going to have the opportunity to affect the composition of that, that toasted layer underneath the char. So you may be able to get slightly different profiles from this than you would with just a straight charred barrel.

There you go. Hello. Once you do To have a buttery taste out of the barrel, so like a sharp knife, for instance, you know real buttery or like, we’ve had a couple single barrel pics where we taste like, you know, it tastes like real buttery or oily. What chemical compound is that coming from?

Well, when we talk about Chardonnay and the butter and Chardonnay that often comes from the mouth, lactic fermentation so it’s actually a microbial a lactic acid bacteria metabolite diaas. a teal is one of the compounds that is most associated with that character in Chardonnay. And certain barrels may enhance that for a couple of reasons. One is some barrels may produce better conditions for the bacteria to do their thing back in we do see a fair amount of oak sugars that are released during the testing process and so it may make it more conducive for some of these organisms to to thrive. Those compounds in whiskey may be something that comes from the fermentation of the of the mash, and gets carried over during the distillation. So you could have similar organisms producing diabesity and related compounds during the fermentation. So, I’m not sure if it’s barrel related but that would be in wine. It’s usually a lactic acid bacteria from mal lactic fermentation that’s making those kinds of characters

All right, Ryan, you got that written down?

So so let’s let’s talk about you know, bourbon and whiskey in itself kind of kind of break us down here and really school is like, where Where’s what’s like a chemical composition or a makeup of really what this looks like and, and kind of help me point me to one of these articles you’ve written to that that can help be also better understand it.

Well, so the transition to looking at at spirits came from just wanting to continue to work with oak and try to understand how composition affects not just wine but let’s look at other products as well. And so we started we started looking into just what’s what’s in different kinds of spirits. And so we looked at not just bourbon but other whiskies as well. So in one of the profiling in the profiling work, we looked at how do Bourbons and scotches and Irish whiskeys and other whiskeys compared to one another. And, and some of the differences there have to do with with new oak versus oak that’s already barrels that have already been used to age bourbon or other products. And and and then one of the other Questions that sort of came along that started the work that I’ve been doing with with Jake lon at Virginia Tech has been just this question of what’s the difference between bourbon and rye whiskeys? And can we? Can we differentiate them? So I guess to break it down is mash bill. Can we see differences in Nashville through the oak that we’re using to age the whiskies in?

Yeah, yeah, kind of start at the top right there like can you can you discern the types of whiskeys by the mash bill after it’s been created from a chemical way to do it and kind of talk about the process of like, how you came to your conclusion to

so it I mean, it started with just a small a small study where we just went to the local liquor store and picked up a dozen Bourbons and it doesn’t dry whiskeys and then did our analysis to see Can we see Can we tell them apart chemically? And I think the profiling paper that talks about bourbon Tennessee and rye whiskies shows that when you look at the non volatile composition, so non volatile means, things that we’re not smelling. So, to show the things that make it smell the way they do or the volatile compounds, those are the things that we can actually smell with our noses. non volatile composition refers to things like some of these folk related compounds that get extracted during barrel aging, but contribute to color they contribute to mouthfeel they contribute to in some cases to aroma but not not entirely. And so we were using the the LC q two off to do the analysis of the compounds that are extracted into these whiskies and what you what we want, you can see in that profiling is before you go too crazy, what’s an L CQ tough. So the LC is the HPLC. That’s the liquid chromatography quadrupled time of flight mass spec. So that’s the instrument that we’re using to do the analysis. So the LC part separates the the individual compounds based on how they interact with the chromatography column. And then as they come out of the out of the LC, they’re introduced to the mass spec. And the mass spec separates whatever is coming out at that time it it separates them by mass, so how heavy the compounds are. And because it’s a quadrupole time of fight, we get really good mass resolution so we can separate things that are pretty similar to one another. And it also gives us an estimation of what the chemical formula is so that we can then really get a leg up on identifying specific compounds that are involved. And when we look at these kind of compounds extracted from Oh, there’s no there’s not surprising A lot of overlap because Bourbons and rise generally speaking are aged in very similar new charred Cass. And so you’re going to extract a lot of the same things irrespective of what whiskey or you’re putting into it. And so Bourbons and rise aged a new cast for example of very different than scotch whiskies aged in reused cast because we’ve extracted a lot of a lot of things in the first use, and there’s not as much left to extract and subsequent uses.

Can you can you like, without because of course, we can’t do it visually. But can you can you explain really how they are, you know, if you were to look at something like how does it look that they’re actually different on paper.

So there’s, there’s a, several different ways we can do it. One of them is just to look at individual compounds and just measure the abundance or concentration of these individual compounds in the different whiskey types. And when you do that, there’s a lot of variability and Bourbons and rise Generally, the concentrations don’t vary that much for things like glycol for some of the oak related tannins to get extracted for any of the any of the things that we’re looking at, using the LC q Tov, they generally look pretty similar. We don’t see a lot of separation. We do sometimes see separation by by producer because they they’re using specific cooperage is so that sort of points to maybe differences that are related to the barrels and not so much differences between the spirits.

What are some of those differences? Like, what what what are the actual compounds that you’re seeing that are either higher or lower and

rye versus bourbon and stuff

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rye versus bourbon and stuff? Well, so in the, when we look at the UK related compounds, we’re looking at things like glycol and Eugene all and we’re looking at some of the some of the wood tannins. We’re looking at. fennel properties, things like kovarik acid and Saran jaw and ceramic acid things that are oak. They’re extracted from Oak, we do we we do so there were several things one is we didn’t see big differences between bourbon and rye. We do see some differences between younger whiskeys and older whiskeys. In terms of the kinds of compounds that are extracted, we tend to see simpler Wood related compounds, monomers so things just like the kumbhak acid, ceramic acid for for like acid that are extracted in younger whiskies and then as you get to older whiskies you start to see more tannin you start to see dimers and bigger,

bigger sort of

not quite tannins, but somewhere between the simple monomers and the tannins you see the smaller complexes of folk related compounds so like lignans, things like syringe or resin all and Liana resin all things that are more, more complicated probably take more time to extract we also see a number of tried terpenoid compounds that are extracted into the whiskies and again, the longer the whiskey is aged, the more of these things you get extracted, and then the other class of compounds that you see Are our lippitt. So fatty acid kinds of compounds that become more oxidized as the whiskey spends more time in barrel. So they’re things that sort of make sense you’re going to have more oxidation the longer in the barrel and that’s going to be reflected in the profile of the lipids in them in whiskey as well. So what we were seeing was more difference between younger whiskeys and older whiskeys. Not big differences between Bourbons and rise.

I’m looking at this table to and with bourbon whiskeys. It seems like there’s more differentiation compounds in the bourbon whiskey than any other. Is that correct? Am I reading that?

Right? Yes, you’re reading that. Right. And I, I think, in part it had to do with availability of whiskeys at the time we did this study. So we when we were doing this, you could find a broader range of ages of Bourbons and you could for rice This was during that time. At a time when right whiskeys were when it was hard to find older rye whiskeys and so most of the whiskey rye whiskey we looked at were younger whiskeys whereas the Bourbons, we had a full range. And so I think part of the reason there were more compounds in the bourbon that differentiated the bourbon rye was we just had a more diverse set of Bourbons than we did for rise in that first study.

Gotcha. I thought it was just proving that bourbon is king to everything.

We could go ahead.

Yeah, I’m okay. That’s my, that’s my hypothesis.

But now that they’re older rye whiskey is available. Again, we could go back and repeat the study and see if we get similar outcomes.

I’m in on that. Let’s do it.

Yeah, right. We’ll use Kenny’s bar.

Yeah, I mean, I’m looking at like, again at this table and and kind of, let’s talk about some of these like, della hydroxy Benz, and all idle I can’t even try

a Benz aldehyde Yeah, like like that.

Yeah. So yeah, thank you for saving me they’re kind of talk about like, what each one of these are really contributing to the bourbon itself too.

Well, so I would say the first thing is we don’t necessarily know what all of these compounds are doing in terms of their effects on the aroma. So that di hydroxy bends. aldehyde is likely a breakdown product from lignin and it’s produced during the toasting slash bile in this case charring process from from the degradation of the lignin that’s in the wood. And it’s probably got I if I had to guess it’s some sort of a medicinal maybe spicy kind of aroma. Nice and so I mean, it’s kind of related related to things like Why call in for method wire call?

All right, what about octane ik acid

so That’s one of the lipids. So actinic acid is a short chain, the eight carbon lippitt. That’s probably coming from one of the younger whiskies I’m thinking, man. And then as you get, so you’re going to see between eight and 1216 carbon chains are pretty typical for what we see in in these products. And then as the whiskey ages, you’ll start to see things like hydroxy October casser, di, di hydroxy actinic acid, so you’ll see you’ll have more oxygen incorporated just as those liquids get oxidized. And that’s going to affect might affect the maybe to a small extent the oiliness it’s going to give you some slightly different aromas. Particularly if you start to get a lot of the oxidized liquids president you start to get into what in cognac would be called the run co character. So that sort of character of oxidized lippitt gotcha.

All right, Ryan, if you’re keeping track here, I’m zero for two. I’m pronouncing these correctly,

but I’m not even trying. So

I appreciate

appreciate the effort, right? Yeah. Well, we don’t really have to we don’t have to do the next one because or the next two because yeah, vanilla and vanilla acid. Vanilla, right. I mean, unless there’s something crazy I don’t know about vanilla. You can you can school us on that.

Now that’s your you’re dead on there.

All right, then there is that deck cannot depend on acid.

Yeah. Economic acid. Good. That’s no, that’s the 10 carbon chain. So you had

I know that one. No, I’m kidding.

And then don’t economic would be the 12. And then you get into into the longer chain ones. But those are those are part from the wood part from yeast metabolism.

Cool. So as you listen How about that one?

And that’s a word related. That’s one of the one of the compounds that’s I mean it’s derived from the word it’s it’s a lignin degradation product as well. I don’t know what specific character it would have but you know it’s it’s going to be part of that set of follow funnels that are that are products of degradation of the wood. So we see similar things would wind as well.

All right, we got three more to go here Ryan. So we got a leg ik acid or allergic, allergic

Yeah, logic. So logic, the logic.

Logic acid is a is a breakdown product from wood tannins, so when you heat would the Alagiah tannins breakdown to illogic acid and then ultimately to Gallic acid. So, it might can contribute some bitterness when it’s in before it’s broken down when it’s still woodturning going to give you some astringency, some some coarseness, some of that woodenness that you sometimes get in Bourbons that may have been at barrel a little too long.

Awesome. Alright, so we got hepta methoxy flavonoid.

hepta methoxy flavonoid that’s why I’m not really sure what that does

I’d say stump the chump but man alive there’s no way that

the common theme though I will notice with this is that you keep saying would and so I guess it just proves that 70% of the flavor comes from the wood.

Yeah, there’s some significant percentage of the flavor is wood derived and flavor and a lot of the aromas are wood derived. So that I mean, so that was part of the part of what we’re trying to understand is just how critical is would to the character of these products and you would guess going in that it would be And it is now in terms of the aroma. We didn’t in this study look at using gas chromatography. So a way to look at the volatile compounds because I mean we you do have different characters and Ryan bourbon in the aroma. And those are not I mean that those are not going to be necessarily wood related compounds, there are going to be some volatile aroma compounds that are related to the mash bill. And that’s that’s something that we have have looked at in a subsequent paper where we worked with a distiller to produce whiskeys have dealt with different mash pills, different different amounts of corn and rye so that we could try and understand that part of the problem better that part of the equation. But one of the difficulties we have in this kind of work is as researchers we don’t have access to what the mash bills are that any of these distillers. Producing and that’s fine. So we have to make some estimation about what what they’re doing but but then we worked with with a distiller to actually produce whiskies of the mash bills that we that we wanted to try.

And so on a budget did they give you to like, go buy these bottles? Like, here’s how much you got spend.

The money we use for this came from bits and pieces of startup funds, different sources. Some of it came from our own pockets just because, you know, we wanted to do this work and we’re interested in it and we really weren’t sure where to turn to to get funding to support this kind of work.

There you go, right. Yep. Kickstarter, self kickstart. Yeah,

well, that’s it. We we’ve kicked that idea around of doing a Kickstarter to try and get funding to do some of these projects. Just because they’re, you know, it takes money to do this analysis and some of it some of it comes from various startup funds and things that we have a little more control over what we can spend the money on. So

I’m in for 10 bucks.

Yeah, man.

I’m not cheap, like any

question. One thing that sometimes you get into whiskeys like real fruity notes where those compounds that are bringing that out,

well, some of those are ethyl esters of some of these fatty acids. Typically, those are the fruity compounds that we see in wine are higher alcohols that are produced during fermentation. And then with the amount of ethanol that’s around you, you get a combination of the fatty acid and the ethanol to produce an ethyl Ester. And many of the ethyl esters have these fruity aromas

yet so while we kind of move on, I’ve got a lot of questions that are coming in through our live chat through here. So I kind of want to get to some of these because there’s there’s some good ones here in the live chat. Yeah, I’ll send you the link here. So. So as we, as we kind of go through here, there’s, there’s a really good one. And it’s kind of talking about barrel entry proof. And I’m not too sure if you’ve done any research on that. And this one might just be your best estimate, guess of knowledge here. But can you talk about barrel entry proof in the effect it would have on the solubility of the compounds that are pulled from the barrel? Because many people claim that a lower entry proof like 107 or 110 results in a better whiskey rather than putting in at something like the max capacity at 125?

Sure. So the first the first thing is we haven’t done that sort of research at all. That’s something I’m interested in doing. And the whole reason we started down this path of looking at distilled spirits was just to get a wildly different entry proof from what we were doing with wine wine, we’re at 15% alcohol. If you’re 125, you’re 62 and a half. So it’s a completely different solvent system, you have so much more ethanol, it’s going to affect what gets extracted from the wood. And so we definitely see if you compare wine and spirits, you will see very different things extracted, because ethanol is a really strong solvent. That’s the difference between 15 and 6062 and a half. You won’t see as wildly different outcomes if you’re looking at 110 verses 125. So there’ll be some differences. That’s still a significantly higher level of ethanol, but it’s not going to be as different as what we see between wine and spirits. The higher the alcohol, the higher the ethanol level, the higher the proof. The more organic compounds you’ll be able to extract

you’ll die Really,

you should extract more at higher proof than at lower proof. But you’re going to extract different things as well. And so and it’s just it’s one of the things that we want to do, you’re going to see a different set of extraction, you’re going to see probably more of the try terpenoids, you’re going to see more of the lipids extracted at higher proofs than it lower. But I don’t know yet. To what extent that would have what it what impact that would have on the on the whiskey itself.

Yeah, it’s it kind of reaffirms, there was a assumption in the chat that said, somebody that took a few classes over independent stave, and they at least independence Dave said they did some data and did some analysis and said that barrel entry proof of 114 produces the most flavor compounds and they had the data to back that up whereas something that can be higher, can Sometimes extract more of the undesirable compounds.

Exactly, you’re definitely going to extract different things that when 25 then you wouldn’t wouldn’t 10 and you’re going to extract a lot of a lot of it’s going to be very similar but you’re definitely you have the opportunity to extract some other things at higher proof that may or may not be desirable, you may get better outcomes at lower. We just, we just haven’t done the work. We haven’t had the opportunity we haven’t had access to the whiskies to be able to do that. We are we are starting to work with a local distiller here to to go down these down these rabbit holes to see what there is to see.

We got whiskey, we can help you out you just let us know. samples.

Good to know. Good to know. Yeah,


In another kind of thing that came up people were kind of wondering, you know, and I think you you kind of talked about it a little bit about not really being able to discern a whole lot of difference between Ryan bourbon based on their mash bill it from a scientific level. But I mean, something that’s like a weeded bourbon versus a rye bourbon. Were you able to find any discernible differences between those? Or is it at the end of it, it doesn’t look any different in science?

Well, so some of it comes down to the tools we’re using. So when we use the LC cute off, and we’re looking at non volatile compounds, what we’re really that’s a that’s a good tool for looking at situations where you have different kinds of barrels, because it’s a really good tool for looking at what you’re extracting from the barrel. And so we can really easily see differences between Bourbons rise, and scotch whiskies or Irish whiskeys, things that are aged in US barrels. That’s really straightforward. Just to see differences in Nashville. We need to look at the at the profile, so we need to use gas chromatography instead. And in this most recent study, we’ve started to use that as a tool. And then we are able to see more differences based on mash bill. We haven’t with that yet looked at Rive versus weeded Bourbons, but that’s on the list of things to do. The other thing I would say is using the LC q Tov, we can see we can differentiate between whiskeys of different ages because a lot of those differences are related to what’s being extracted from the barrel. We can see some differences between producers based on the barrels that they’re using. And, and so it’s a tool that could be used for things like is this whiskey really what it says it is, in terms of age or producer, I think with some work and with the right set of library standards We could start to use this as a tool for authentication in case in case there was some concern about a whiskey being what the label says it is. We’re not there yet, but I think we, it’s a tool we could use for that. The scotch regulatory agencies are are using these kinds of tools to verify authenticity of scotch whiskies, for example,

do you think that you could look at you know, whether using gas chromatography or HPLC, or anything like that, to sit there and look at and I don’t know if you’re this deep into the bourbon world, with dusties are basically Bourbons that were from the 60s 70s and stuff like that, versus what’s produced today. I mean, do you have any hypothesis on on kind of what that would look like?

Well, lot Oxygen.

Oxygen would certainly be one of one of the key things to be concerned about it but assuming that the the package was well sealed and you’re not getting a lot of it. oxygen into the folder whiskey. It could be a toll to go back and look at route, for example, the question of entry proof. Because you go back to a certain time when 10 was more common than, then we’re where we’re at now. So there may be possibilities to look at that. It’s also, you know, to look at differences, differences in production practices as well. Some of that would be gas chromatography. Some of it would be liquid chromatography. You know, it’s something we are interested in doing. getting access to those kinds of samples is, is not always easy. But we’ve had some discussions about doing that kind of that kind of work

need with jack rose, and just go through their whiskey collection.

Yeah, I’m sure bill Thomas would love that. Yeah.

All for science. All the name of research. That’s how science Yeah, absolutely,

you know, start to make bad bourbon too.

Yeah. There we go. Right. We’re gonna sell. We’re going to sell license plate holders with that on it now.

That’s right.

So, yeah, so we’re kind of we’re kind of creeping up to the top of the hour here. And I kind of want to, like finishes on on a strong note, you know, is there is there one thing that you took away from a lot of this research that the average Joe can can make a like a better informed or buying decision or anything like that? Or like, What’s it? What’s a big takeaway from from everything that you’ve been doing here?

Well, I mean, I think we touched on a little while ago that it’s, it’s a pretty, pretty large percentage of the aroma and flavor in distilled spirits comes from the cast that it started with bourbon, we definitely see some differences between producers we definitely see differences in the age of the whiskey and You know, there’s some some really, I mean, it’s, as you say, the more you know, the better, the better you’re going to be. And it’s interesting just to see how these things play out as you look at younger versus older whiskies, and a fair amount of this work has been done during the period of time when the industry was sort of scrambling to have enough. Older, older Bourbons, older rise for the marketplace, there was a lot of demand. And so it’s, you know, some of this, it’s, you can see some of that challenge and the results that we’re looking at in terms of being able to maintain the age of the products that are they’re putting on the marketplace.

Fantastic. And I guess I got one more question that came into the chat because it’s really going to marry your two worlds here. Right. So what about when a whiskey is aged in a secondary cask like a like a wine or a port casks like envy and some other ones that are out there? Is there a type of like chemical reaction that’s happening with this blend? You know, kind of give us your, your kind of take on that.

I mean, we definitely didn’t really touch on this because it was more in this in the scotch world. But when you’re looking at scotches, there’s this big differentiation between scotches that have been aged in bourbon barrels versus Sherry butts. And we can we can pick those out night versus day, the ones that have aged aged and cherry casks look very different from the ones that have been aged in bourbon casks. And I would expect we’d see the same sort of thing if you started looking at other whiskeys that have been finished in Port barrels or Zinfandel barrels or peanut or barrels or whatever other kinds of things that are out there you would see the influence of that other product as well. Some of it is direct influence from the product itself. So the port or the Zinfandel but somebody It is also just differences in wood, you’re going to see some differences because of toasted word versus charred wood. There. I mean, there’s there there are definitely things to see. And we can also I think, see when we’re looking to Sherry casks, we can see differences not just between Sherry and bourbon, but between Spanish oak Sherry casks and American oak Sherry cask. So there’s there are definitely characteristics of the ones that shine through in spite of the influence of the Sherry to

it all comes back to the wood

back to the wood.

And we go, I think we can our conclusion or is that we need barrel statements instead of a statements like what barrel was in the char level, that long? You know, the conclusion.

It all comes back to the word.

Yep. This is fantastic. You know, Tom, thank you so much for coming on the show today. And really, like I said, schooling up I’ve I fumbled on more words than I have, I think in a long time trying to try to get him out here and really, you know, educating our listeners and for us. For myself, I think this was super interesting. Just to kind of see this from a data perspective. In my business, we always say that the data never lies. And so when you look at it, of really what is being influenced by to the whiskey via as we just said, all comes back to the word it’s, it’s super interesting. In my opinion, we see this but I also want to let you give a opportunity to plug where people can either find out more about you or researching more about you or you’re looking at some of your papers. And if we’re going to look after this, so hopefully, we’ll get some thumbs up and green lights and and you’ll be able to find some of these papers on our website when this podcast is is aired. So go ahead and give yourself a plug there too.

Well for Well, it’s absolutely been my pleasure to do this, I appreciate the opportunity to come and talk about some of this work. And I’m glad to see there’s interest in in this sort of thing because it can get pretty dry and academic at times. So

you feel like you’re just like yelling in a cave, like,

good to break it down and and talk to folks who who are passionate about it and appreciate what the implications for some of this might be. So I really appreciate it. And again, if you want to learn more about what we’re doing, some of it is posted at the Washington State University Department or medical terminology Program website. You can Google that and it’ll pop up and you’ll be able to find find me somewhere on that on that web page. So happy, happy to answer questions that people might have as

well. You got it. Alright, so you got questions. Start googling, and good luck.

Good luck.

But But seriously, thank you again for coming on the show. So reach out you can try to find time out there, you can always reach out to us to team at bourbon pursuit com. Follow us on Facebook, Twitter, Instagram to see what we’re drinking, what we’re talking about where we are today. And if you like the show, and you want to help it grow, we would appreciate it write a review. And if you want to be part of these, as I mentioned, you get to be here during the live chat. You can support the show on Patreon pa te r eo in comm slash bourbon pursuit. Ryan go ahead and close this out.

Yeah, Tom, thanks, man. That was that was enjoyable. I was trying to wrap my head around these concepts and try to talk intelligently about it. Yeah, I think you know, science you try to you try to do something so you can replicate it and you know, have something that’s proven nothing time and time again with spirits and bourbon. You just can’t replace that human element. And there’s so many variables with you know, nature and then the human element of making a consistent product. So it’s interesting And I hope there’s more continued research about it because it is fascinating.

All right, terrific. I enjoyed it. I enjoyed it immensely. And thanks for the interest and yeah, absolutely. The human element is a huge part of it. And a lot of this was really focused on what are the things that matter what are the things that the human element can focus on to get a better outcome?



All right. Cheers, everybody.

Transcribed by https://otter.ai

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