Tuesday, November 18, 2014

Why even bother with Craft?

So the buzz has died down a bit on this particular topic so maybe it’s time to look back at what the fuss was or is about and who’s asking. There are a lot of people asking the question: What is craft, who is making craft stuff, and why should I care?

There is a huge spectrum of production styles and the fun begins when the dust flies from everyone who thinks that what they do is the only way to be craft. These are my arbitrary categories but I think there are some guidelines here that can help people to understand what it is that the spectrum of production methodologies includes and how little or how much some people are doing.

1. The Earth to Glasser
This category is the purest and in many ways the most difficult. It’s certainly the most expensive way to make distilled spirits (really anything) and it’s what you pay a premium for. This production includes at the very least processing the fermentation substrate (grain, fruit, potatoes), cooking it, fermenting it, distilling it at least once if not multiple times processing the alcohol into a spirits category (whiskey, brandy, eau de vie, vodka, liqueur) barreling it if necessary, bottling it and off it goes to shelves. Some people in this category actually grow the fruit or grain as well. These people work hard to make that product and there is a lot of sweat that goes into a bottle of spirit produced this way. These are the people that are most hurt by products that go on the market with dishonest labeling because like shadows on a dark scary night, once you've found one great story to be bullshit it's easy to see bullshit everywhere, baby with the bathwater style. The thing is that many of the big producers like Scotch and bourbon distillers have been doing this for decades. The hardest part about becoming a producer at this level is that you have to spend hundreds of thousands if not millions of dollars to build the facility to make this stuff. The big guys have been around long enough that their facilities are built and paid for. Getting into this market is hard work and takes time and small craft whiskies are at a higher price point for similar production methodologies but are working on paying for their dream right now which sometimes includes waiting years for spirits to come out of barrels.

2. The Distiller and Blender
These folks often make some of their products as above, whiskeys for instance, but may have some bulk alcohol that they buy for one or more of their products. An example would be bringing GNS/NGS (Grain Neutral Spirit) into their plant and perhaps distilling it with botanicals to make gin or adding flavors to make liqueur. Another example is carrying a blended whiskey purchased already aged and selling that while waiting for your own to age, or blending the two. This is done for one of a variety of reasons:

  • The producer can’t afford the equipment to make a neutral spirit and so they source that part of production out, buying it on the bulk market.  
  • They are selling a sourced whiskey while waiting for their own and/or are proud of their sourced product that they sell as such.
  • The marketing and business side of the company sees how much cheaper it is to source rather than produce. 
With an honest company you’ll know that they buy the alcohol for their gin and are really proud of the botanical mix they use or the fruit that goes into their liqueurs. The ones to look out for are the ones that don't tell the whole story. Some of these folks buy NGS or whiskey and blend it with their own, or just bottle bulk whiskey but don't talk about it. They'll spend a lot of time walking you past their grain bags but never really get around to telling you the whole truth.

3. The Blender
This is the distillery that has no fermentors and possibly no still. They bring in all bulk spirit (whiskey from other producers, NGS, bulk rum), bottle it with their branding and tell a story. Hopefully this story is: “We source the best stuff we could possibly find, blend it proudly and sell it to you as something we love”. At its worst this story is: “We made this from scratch from a super secret recipe!”.

4. The Total Bullshitster
Basically anyone who throws a flavor in a bulk spirit and then starts up the bullshit factory, or buys bulk whiskey and tells a story about America while buying from Canada, buys NGS from an ethanol factory in the midwest and talks about how their pot still is the key to craft while pretending their still is doing something other than allowing them to use the words “distilled by" legally. I don’t have any problem with methods of production (I don’t care what’s in a capri sun) but I want to know that the story is true…unequivocally true. If the ingredient list for capri sun called high fructose corn syrup: " Natural heritage maize extract from small family farms, hand picked by Juan Valdez"...I'd have a problem. That's Bullshitster talk and there are so many products like this in the world.

Trouble and controversy for the Bullshitsters exists because they're taking the first 3 categories, which are totally legitimate, and using them rather than being them. There are brands that have flagrantly abused the lack of information out there about sourcing to pretend they are something they're not. There are spirits out there with really compelling stories that are talking about grain and farmers and community when what they’re doing is buying bulk spirits, tossing it into a still for a quick redistill and using it for vodka and gin or bottling someone else's whiskey as their own with a pretty lie attached. The companies that haven't been caught yet are still hanging on to their stories hoping you won't notice.

I sit on the ethics committee for the ACSA (American Craft Spirits Association) and I was pretty proud of the statement released a few weeks ago that the ACSA isn't as concerned with defining craft but that the primary concern of the organization is truth. I’ve seen flavored vodkas with chemical flavors talk about antioxidants from berries in their marketing materials because one flavor is called acai, whiskies that are completely sourced that have such elaborate stories that it’s amazing to me it took years for the untruth to leak out, I’ve heard the line: “It’s just marketing spin” and the person speaking was unable to tell the difference between the truth and his complete fabrications, had bulk suppliers tell me I should dump NGS into my whiskey fermentor to increase my yield because nobody cares anyway. My least favorite line from this side of the industry was: “No one really wants to know how their sausage is made”. Anyone who takes the time to read the story is buying that story and they care very much about where their sausage is made or they wouldn't spend the money. You have to be a true cynic to sell a story that people love while completely defiling it in private.

On the other end of this spectrum I have spent time with people whose integrity is simple and honest and whose attention to detail is breathtaking, who build their businesses for decades, people who build their communities with their businesses and who don’t differentiate between the two, people who have always been up front about what they do and are incredibly proud of their sourced products and should be, people who make everything from scratch and have grown quickly and gotten all the best attention for not making the easy choice to compromise.

Each one of those statements is a link to a company that represents what to me is the meaning of craft for this industry. These are hard working, innovative, honest people whose word you can trust, whose integrity is obvious and about whom there will never be some stupid scandal regarding what is in their products. Some of them I’m lucky enough to count among my friends so I have a bit of a bias, but they’re my friends because of the above. These are people that inspire others because they believe that truth is important and simple, not nuanced with “marketing spin” in order to sell product. They tell the truth. That is craft. One rule I have for life is: don't do anything you wouldn’t brag about don’t work with people you wouldn’t want with you in the trench. This is a great rule for craft as well. If they can't brag about what they do they shouldn't be doing it.

You should bother with craft products. You should do it because there are people behind the products that work incredibly hard to adhere to an ethical ideal. They believe in things and stand by them. They sacrifice rapid growth and low overhead for honesty and idealism. Support that. We need idealism at this time in our culture. It’s why the last couple of decades has seen such huge growth in story driven products. We want to believe that you can make something you love and it will support you and your family. Make this true. Buy things from people who believe it. There are huge pressures as a company grows to compromise ideals and many brands fold. Let them...fuck them. Support the ones that don’t, drop the ones that do. Make it important for companies to retain their ideals and the world will change because the engine for change is the dollar you’re going to spend and the organizations you support with that dollar. Even as companies fake up cool stories to try to capitalize on this wave, don't let them make you cynical. Just go find a real one. Find someone you admire and buy what they make. That's craft!

Saturday, October 18, 2014

Plants, sugar, fermentation

So plants and animals spend most of our time and effort taking in nutrients and storing them for use later as energy sources. We also take in carbon sources that probably could be used for energy and use them structurally, to build ourselves. The way we do this is to take whatever it is we're consuming (CO2 for many plants, plants or tissues for animals), breaking it down to some subcomponent, and then assembling a polymer (chain) that we can store in some tissue or other or build some tissue or other from it. In plant material these polymers are cellulose, cellulobiose, glucans, lignin, pectin. In animals we're talking glycogen, proteins, and others.

For the purposes of a discussion of fermentation in the context of brewing and distilling, plant polymers most especially starch is going to be our primary concern here. Starch is a form of energy storage used in seeds and tubers. Seeds want to store energy so that when they germinate there is enough energy to fuel the growth of the sprouting plant. Like the yolk of an egg, the starch provides the calories to get growth going, during the phase before leaves have appeared for the manufacture of energy sources from photonic energon particulates (sunlight) and carbon. Once the plant has leaves and roots it no longer needs that starchy internal energy source as it can make its own.

Starch is a chain of glucose molecules. Glucose is the simplest of sugars. It's a 6 carbon ring with some OH groups hanging off the sides. Those OH groups are active groups called alcohols in organic chem. If you strap 2 glucose molecules together you get maltose, a disaccharide that gives malt shakes, malt balls, and many beers their unique and amazing flavor.


Keep strapping a few of them together and you get dextrins, short chains of sugar that cause thickening but not much sweetness (body and mouthfeel in beer). Strap a couple thousand glucose molecules together into a long chain and you get a starch molecule called amylose. Add some branches and you get amylopectin. 

Amylose
Amylopectin


These polymers are found in grain and starchy tubers. They are great energy sources for the seed/sprout...and of course for yeast. When we set about making beer or whiskey, job number one is to get the starch freed up from the structural polymers and containment vessels in the material. We need to free the starch because the plant has encased it and kept it dry so greedy microbes can't get access. If we get the starch freed up and into water, we can use enzymes to break it down into simple sugars that yeast can metabolize and make into alcohols and aroma/flavor active compounds. 

Basically you mix grain and water, heat it to break open the granules that the starch is hiding in, heat to a couple of enzyme ideal temps and allow the enzymes to break the starch down. Once you've done that you've got a sweet tasty mix that is full of simple sugars. Eastern Europeans used to drink this after a very short fermentation to add a touch of carbonation, as the first sodas. Yeast eat sugar to produce alcohol, CO2, and heat and they do it pretty quickly. Give them a few of days and you're all set with something distillable.

The other plant polymers made up of glucose are things like cellulose which can't be broken down as easily. Cellulose is what the supple green plant tissue is made of in a new bud or leaf. There's lots of energy stored here but it's really hard to liberate as the bonds holding the glucose molecules together are much more stable. It's sort of like the nuclear energy thing. The amount of energy in a bowling ball is greater than all of the bombs we've ever set off. The thing is that the bonds holding the material together in that ball is so great, that we don't have the ability to liberate it without investing so much energy it's not worth it. Cellulose has to hold plants together where starch has to fuel them...so it's meant to be broken apart. Cellulose is exposed to all of the airborn microbial life our abundant Earth has to offer and is pretty resilient.

Lots of plants have free sugar available without enzymatic treatment. The white powdery layer on the outside of a grape or apple has a good deal of yeast in it. Yeast, like bacteria, are ubiquitous meaning they are very literally everywhere around you. This is why you can leave flour and water out and start a bready yeast culture for your sour dough starter. Distillers used to do the same, capturing live local cultures and testing the flavors of their particular exudations (booze is pee...call it sweat if that makes you feel better). These days we most often use purchased or cultured yeasts, some are using a combination of both.

Tubers (potatoes) are really the same deal although it's a bit simpler to liberate the starch from a potato. Once the starches and sugars have been consumed and distilled off there is a good deal of material left over. Some of this goes to feed animals, some goes to biodigesters (to produce biogass that can go into boilers like natural gas) from another kind of fermentation, some of it gets composted, some of it gets spread directly on fields.

If you're starting from grapes or fruit it's really much simpler as you don't even have to add yeast to get things going, although it's advisable to control your culture for consistency's sake. When breaking down starches it's inevitable that not all of the starch will end up as the simplest sugars (glucose and maltose). Even slightly longer dextrins (3+ glucose) are difficult for yeast to do anything with but there are bacteria that are happy to get involved. LAB (lactic acid bacteria) love them some dextrins but they produce lactic acid. Some distillers love this some not so much but regardless it needs to be controlled. This isn't really an issue in fruit as the sugars are already simple so the yeast are in heaven. There are certainly infections that can occur later on if conditions aren't sanitary.

That's all I've got for plants, not that this is comprehensive but it's the basics.
Power to the Plants!

Thursday, December 5, 2013

Theory of Fermentation...at least the first lesson



I'm writing a book about distilling for the technical distiller and am toying with the idea of putting all of the info here, asking for feedback and then publishing it later as well. Let me know what you think of this idea if you want down in the comments...but until I decide, I'll throw some material at the wall and see what the splatter looks like.


Theory of Fermentation

               I like to start with the definitions so here’s fermentation: Fermentation is metabolism that occurs in the absence of oxygen. Back into the wayback machine for some highschool chemistry/biology...Respiration is breathing, right? Aerobic metabolism means consuming energy/carbon sources while oxygen is present. It’s what you do. Anaerobic respiration is a very ancient metabolic process that microbes make use of. There didn't used to be much oxygen around after all.

               Categorizing microbes for their respiration/metabolic styles we get:

1.      Obligate aerobes: organisms that can only utilize aerobic metabolic pathways. They die in the absence of oxygen (or go dormant if they’re tough).

2.     Obligate anaerobes: organisms that can only utilize metabolic pathways that do not require the presence of oxygen. They die or go dormant in the presence of oxygen.

3.     Facultative aerobes: These can survive in either environment but prefer the aerobic and are more efficient there.

4.     Facultative anaerobes: These can survive in either environment but prefer the anaerobic and are more efficient there.

Yeast are facultative aerobes. They thrive in an oxygen environment but if the oxygen gets used up they switch modes and make the stuff they need to make through other means. I’m not going to go through an extensive review of metabolism but I will give some background here as it’s easy to overlook the purpose of metabolism, and an understanding of the purpose of these metabolic pathways helps the distiller to trouble shoot and improve yield if you know the motivations of your actors.

The primary purposes of metabolism are twofold: 1. to produce energy, 2. to produce the materials necessary to build and repair cell tissues. Metabolism takes a carbon energy source, strips it down to component parts and uses pieces of it for these two purposes. Sugar is a great carbon and energy source. Breaking the bonds of that ring structure makes electrons available for the cell’s machinery to convert to stored energy.

Aerobic respiration among yeasts is used for reproduction, or biomass production. With oxygen present the yeast cells will reproduce quickly adding yeast cells fast. If no oxygen is added to the environment they will consume all of it and when it is gone switch to anaerobic metabolism. If you bubble air or oxygen through the media, they will continue building biomass. This is the essential of yeast propagation. You have a carbon source (sugar), you add yeast cells and continuously bubble air or oxygen through the media and build an extremely high biomass which can be used to pitch or inoculate a beer or mash. When brewers collect yeast from the bottoms of their fermenters, they are debilitated because of the stressors they are subject to during the fermentation process. Our brewer pulls out a clump of yeast, oxygenates the mash he is pitching into in order to encourage the debilitated yeast culture to propagate (prop up) to a higher cell concentration for the next round of fermentation, and then allows the mash to go anaerobic after the yeast culture is healthy and thriving. Once the substrate is void of oxygen, anaerobic metabolism occurs and that's where the fun happens.

The yeast cell life cycle in a fermentation cycle is characterized by a collection of important stressors.
                                    1.      Osmotic stress
                                    2.     Solvent or alcohol stress
                                    3.     Nutrient scarcity
                                    4.     Competitive inhibition

Remember osmosis? Osmosis is the tendency for a solute (substance that is dissolved in solution) or solvent (substance that is doing the dissolving) to travel from a position of higher concentration to a position of lower concentration through a membrane. The yeast cell wall functions osmotically and the term solvent stress describes the stress the yeast experiences at the beginning of the fermentation when there is a relatively high concentration of sugars in the aqueous media. That is to say there’s a lot of sugar that wants to push into the cell because the membrane facilitates the movement of material in or out of the cell to balance concentrations on either side of itself. If too much sugar passes the membrane into the cell it can damage the cell.

High gravity brewing or mashing involves fermenting from a brix of 20 or higher. This is a stressful situation for a yeast cell, and although I'm not totally familiar with the mechanisms yeast use to survive this particular stress, I know that ordinary yeasts will not ferment to completion in a high gravity environment. Ordinarily what happens is that the yeast makes it through the initial fermentation and then stalls without consuming all of the sugars because other stressors build up and they just give up. If the yeast is not equipped for high gravity or there are other stressors present such as a dearth of nutrients, the yeast will be debilitated by the effort of dealing with the high gravity and may stall out later in the fermentation. 

Solvent or alcohol stress basically defines for the inevitable fact that our yeast are committing suicide by excreting substances that are ultimately toxic to itself. Alcohols damage cell walls as the concentration climbs. Yeasts are constantly being bred which are resistant to higher concentrations of alcohol but it’s pretty uncommon to go over 16% alcohol without some extreme measures.

Nutrient scarcity can define either the condition that develops as the yeast consume all of the sugars and nutrients in the media and deplete it over time, or a condition that comes from improper mash management at the beginning. There are entire books on the trace mineral content of water for mashing and PhDs have been written on the proper concentration of Nitrogen and minerals in a yeast nutrient.

Competitive inhibition is what happens when some other microbe comes to the party and does something to the environment that inhibits yeast activity. A very smart man and someone dear to me used to say that yeast are the water buffalo of the microbial world. They’re big and dumb and do their job just fine as long as you can keep them from walking off the cliff. Any microbe will have mechanisms for gaining an edge over its competitors. The most common inhibitor in the microbial arsenal is acid production. Lactic acid bacteria (LAB) pump out tons of lactic acid (the same acid that gives many cheeses their tangy appeal) to lower the ph of the environment so that other microbes struggle. 

This is one of the most effective competitive tactics. LAB are great at consuming dextrins that yeast cannot so a great argument for the understanding of metabolic pathways such as these is that if your mash goes sour and little alcohol is produced, it often means that you are not getting complete saccharification. You are not breaking your starches down completely, leaving dextrins intact. Yeast can’t metabolize them quickly but LAB can, so they are guzzling the dextrins pumping a ton of lactic into the media stalling out the big slow yeast who give up like spoiled 4 year olds on a pout.

I'm stopping here for now. Stay tuned dear reader.

Monday, August 6, 2012

Oak aging 2, other questions

Here's another post on the wonders of whisky and what happens when you put it into a barrel.

First I'll repost the 3 questions I hear most often in reference to oak aging of spirits.

1. What does the barrel aging do?
2. If oak is good why not try other woods?
3. Is there another way to age whisky faster?

I tried to cover question one in post 1 on oak aging, I'll do number two here.

First off, many other wood types have been tried for holding liquids and aging wine and spirits. Keep in mind the current wooden barrel is known to date back in basic design and shape to the ones the Celts used as early as the third century B.C. That is plenty of time during which curious people could experiment.

To give a quick and incomplete list of woods that have been tried in the U.S. and Europe: red oak, chestnut oak, sugar maple, yellow birch, douglas fir, beech, black cherry, mulberry, spruce, pine, elm, and many more. This post is going to end up being more about why oak is used, rather than why not other woods, but that's because my experience with other woods has mostly been unpleasant.

The list of things you want in a wood for aging spirits
1. It is not excessively porous
2. It does not contribute unpleasant characteristics
3. It contributes good flavor and aroma
4. It is workable enough to be shaped into a barrel.

When you take these four points into account the only wood to pass the test for long term storage and aging, is white oak of the Quercus family. The rest of the woods above, and the many others not listed, fail at one of these four points in the long term. There are between 9 and 12 species of Quercus white oaks that are commonly used. The two major divisions are American oak and French oak. The two lend very different flavor characteristics but the features that make them liquid tight are similar.

Porosity: Think about what a tree must do to survive. It has to bring all of the water it needs to stay alive up from the ground to the canopy. Trees have to be extremely adept at transporting liquid up and out. That is a major problem in a barrel. Liquid inside the barrel penetrates into the wood during the aging process. In oak, most of that liquid makes its way back into the barrel, but in other woods the liquid is able to move through the natural conduction channels and leak out causing major losses. In a standard 52-59gal oak barrel the loss is ~5% per year (the ~ means roughly) which is bad enough. Oak luckily has a couple of features which are unique and keep this loss to a minimum.

Oak wood has two major anatomical structures that make it liquid tight. They are called tyloses and medullary rays. Basically what they do is prevent liquid from traveling longitudinally to the ends of the staves and leaking (tyloses), and prevent liquid from leaking out through the side of the barrel (medullary rays). Almost all other woods leak from the stave ends because they don't have tyloses blocking longitudinal conduction. The medullary rays on most other woods do not span multiple conduction cells the way white oak rays do. The way the staves are cut during barrel production makes careful use of these structures to retain as much volume as possible in the barrel.

Flavor and aroma characteristics: Oak wood is made of cellulose, hemicellulose and lignin. When the lovely green and supple buds appear in spring they are made of cellulose and hemicellulose. When the material becomes brown and hard it is because the tree is laying down lignin, which is its solidifying encrustant. Happily, in oak it is made out of phenolic components that are pleasing to the pallet. A phenolic compound is a ring of carbon atoms with some other compounds attached. These are known as aromatic rings by chemists because as they were being isolated in the nineteenth century it was noticed that as a group they smelled nice, or so the tale goes. Examples: vanillin, guaiacol (parsely, spice), eugenol (clove). The other great thing about these compounds is that their flavor thresholds are relatively low, so it doesn't take much.

While many other woods have lignin/phenolic content they are often in the company of compounds that have unpleasant sensory characteristics. These other woods may be appropriate for brief exposure as flavor accents but they are not typically used for long term storage or barrel production. The other thing I should say is that over the last 25 years wine and spirits makers have taken to tweeking their products by adding chips of oak wood to their barrels to get some wood extract they're not getting from their barrels (a professor I worked with at Michigan State pioneered the practice). There's probably plenty of room for experimentation with this type of tweeking using alternative woods to add unusual flavors and aromas to spirits, and I we're starting to see some of this in the industry.

Workable: Oak is a hard wood, but is remarkably supple under the right conditions. The process of making a barrel is multi-step and goes like this: drying, seasoning, heating and shaping, toasting or charring. Under the influence of heat, oak wood becomes nice and malleable so it can be shaped into that familiar bilge (the widest part of a barrel) shape. The bilge angle and hoop structure are part of the barrel's liquid tight nature. Many other woods are either too brittle or too soft to hold this shape.

White oak is a big part of the magic of brown aged spirits. Many people don't even know that all spirits are clear when they come off the still. All of the color and much of the flavor of aged spirits comes from the oak. A major contributor to this is the heat treatment of the inside of the barrel, but that could end up being a hefty read so I'll save it for another day.

What distillation is

Distiller's Log, Feb 4th 2012

There isn't much construction yet as we're waiting on inspectors, electricians etc, so I thought I would do a technical post. I will be posting with info on our spirits, but also on distillation, aging, tasting, fermentation, etc...so here's one on distilling.


Distillation is how you turn wine or beer into brandy, whiskey, or vodka. It's defined as the separation of volatile compounds by their boiling points. I'll start out with high school chemistry and take it from there. The boiling point of a mixture falls somewhere between the individual boiling points of the components within the mixture. The greater the proportion of one component the closer to it's boiling point will be the mixture.

Boiling point Ethanol: 78.6C
Boiling point Water:   100C
All ethanol distillation occurs with the vapor and the liquid somewhere between these two temperatures.

A still is basically a pot with any number of things hooked up to it. In the simplest stills there's a helmet (a big open copper top)  and then a condensor (something with cooled metal surface for the vapor to condense on). These are called alembic stills and are used to make Scotch and other whiskies, rum and many of the more flavorful spirits. They are made of copper because copper is a reactive metal and is great at removing unpleasant compounds from the vapor. Alembic stills are excellent for flavored spirits as they don't have much tech attached for purification and allow a lot of flavor to come through. The downside is that there isn't much control or ability to alter the distillation process. It produces what it's going to produce and most of your product is controlled by the fermentation process.

A more complex setup would have a column of some kind after the pot and helmet or rather than a helmet. The column has plates inside, on which the vapor condenses and then revaporizes. Each time this happens the percentage of alcohol in the vapor goes up. This is called rectification. Given enough plates you get 96% alcohol, which is the highest alcohol you can get with distillation alone. A short column of 3 or 4 trays can be used to make more lightly flavored whiskey than an alambic still might make, or it can be used to make a spirit that is very light and clean, with high rectification. The short columns are indespensible for the production of eau de vie, brandy, and other fruit fermented spirits, and are also used for whiskey, rum, etc.

In the course of distillation there are a series of cuts made chronologically. These are made differently in different traditions but the principles are the same.

1. Heads cut
Mostly consisting of ethanol and water, the heads cut is the first stuff to come out of the still and has a collection of other components that have lower boiling points than ethanol. Acetaldehyde, Acetone, Ethyl acetate, Methanol among others have flavor and aroma characteristics you might describe as fruit, floral, finger nail polish remover, marker, or solvent. Although some of those sound strange for something you drink, they are an important part of the flavor/aroma profile of many spirits. Most of this early cut is removed but low concentrations of these compounds are either included or reintroduced to later distillations. The bulk of the heads cut is just disposed of. We use ours as a spray on sanitizer.

2. Hearts cut
This is the spirit itself. The distiller makes this cut by smell and taste and this is the only part of the distillation you will ever drink. Many distillers make a big deal about only including the hearts cut of a distillation in their bottle. If they include anything else no one will buy what they're selling.  The hearts is also primarily ethanol and water but there are hundreds of compounds that can be solubilized in either the water or the ethanol to provide flavor and aroma.

3. Tails
The tails cut is disposed of like the heads, or rectified to neutral for use in gin or for fortification. This cut has many alcohols in it you wouldn't think you'd want such as propanol, butanol, isoamyl alcohol. These sound terrible, but if you drink whiskey, rum, or basically anything other than vodka, you are enjoying the lovely flavors these alcohols provide. Again this cut is made at the distiller's discretion and anything that gives you a serious headache had a tails cut that was too generous.

In the figures below you can see some data collected during a vodka run. The x-axis is time and the y-axis is concentration. What you're looking at is the change in congener (heads and tails) concentration during the vodka run. The heads figure stops at 250min because not much other than ethanol and water are coming out until figure 2 starts around minute 620.  This data was collected using Gas Chromatography which is a great way of looking at these kinds of things.

The heads cut was finished at about 35 minutes and the tails cut started at 640. On the heads side clearly some of these compounds make it into the distillate but by the time they are diluted into the hearts, the concentrations are very low.





While the distillation and the cuts are very important many mistakes are made in the fermentation. This is really where all of the flavors are made and by the time it's reached the still, many serious fermentation faults just can't be fixed.

There are other things within the alcohol water matrix. Remember those two temps above between which all ethanol distillation occurs? Some compounds with much higher boiling points can be found in spirits because they are soluble in one of the liquids. For example fatty acids with boiling points as high as 200C can be found in whiskey because they are soluble in alcohol, so they travel over with the vapor. These can provide flavor and/or mouthfeel and are important in aged spirits. Another example would be phenolics from the grain. These travel over and produce the grain flavors, and tasting notes like spice, caramel, smoke, and many more.

Thanks for reading,
Johnny
Head Distiller