Back in June at the AHA conference in Baltimore during a talk on sensory analysis, I was challenged to be aware of and identify 10-15 smells around the city as I walked.  The next day I did exactly that, walked through the city and smelled things. For about 6 miles I smelled things; Cigar smoke, a woman’s perfume, the green of the trees, steam and metal from a manhole cover, the salt in the air at the aquarium, smoke and char from a restaurant’s grill as the door opened, the wood trim in a bar I visited, and car exhaust.  I’ve always liked driving with the window open in new places and smelling the air of the forest, a mountain road, or a river bank but this exercise challenged me to really think about what I was encountering as I walked. Since then, I’ve done this often, walked and smelled things, walking gives me time to figure out what it is I am smelling and to interact with whatever it is.

Assigning a word to describe a smell is a difficult and extremely complex thing for humans but we do it and do it fairly well, to the tune of thousands of odors.  We can train ourselves to be better at it (as chefs, beverage judges, cicerones, sommeliers, master blenders, and many others do) and we can learn new words and associate experiences to aromas we encounter.  To perceive and identify an aroma, we first encounter molecules in the air which are vaporized.  These molecules get in the mucus inside our nostrils.  Inside the mucus there are olfactory receptor cells that can tell there is an odor present.  These receptor neurons then tell the olfactory bulbs at the back of the nose what odor is present.  The olfactory bulbs are part of the brain.  The odor message is sent to our “reptilian” brain, the most primitive areas that access and affect emotion and memories.  There we are reminded of experiences, people, and places that are attached to the odor perceived.

The limbic system, which is this primitive area of the brain, has to then communicate with the many other areas of the brain that deal with language such as Broca’s Area and Wernicke’s Area.  Language happens in many places in human brains and many linguists think that as language evolved it took residence in a variety of areas that were performing related duties such as facial recognition, spatial awareness, seeing color (to find food), depth perception, counting, and knowledge of dangers.  Linguists that study speech disorders find that different areas of damage to the brain cause different kinds and levels of severity of speech disorders.  In some cases, with speech therapy, we can relearn a lost speech skill in a different and healthy area of the brain.

Once we identify an odor we have to find the right lexical item (word) and syntactic frame (grammar).  An utterance also needs morphological and phonological coding, these are the processes by which we form syllables, stress, and decide on how and in what order to use our bodies to make the sounds.  After all that, comes the hard part: articulation.   The brain sends messages to your lungs, larynx, glottis, tongue, throat muscles, lips, and jaw to perform the appropriate movements and create sounds.  Someone has to understand you of course; so the sounds are heard and the process of the listener begins.

Some of my favorite memories which bring very distinct aromas to mind are the memory of finding raspberries in the hot sun at my grandparent’s place during late summer and having the berries burst as we picked them then licking the juice off my hand, the time that a coworker identified acetylaldehyde as “Halloween”, and working with my dad either in his shop downstairs sweeping sawdust, soldering a circuit board, or at home cooking together as sesame oil hit a hot wok.  These experiences helped solidify the aromas of raspberry, pumpkin (hay and green apple too), sawdust, sesame seed, toasty or nuttiness, warm metal, leaf, woodiness, tree bark, and many others in my memory and attached a lexical item that I can pull when I encounter them again.

I was able to practice this skill this past Thursday as I visited some of the distilleries on the Bourbon Trail in Kentucky.

If you have always been wondering what makes bourbon actually bourbon, Click here!. You can find hundreds of reviews of the many wonderful products (and availability where you live) from Jim Beam, Willett, and Buffalo Trace online as well as detailed information on their onsite tours.  These tours offered walks through their production, rackhouses, bottling processes, and a taste at the end.

Each distillery has a number of rackhouses (sometimes called rickhouses), where the bourbon is stored once it is barreled.  I asked two of the tour guides we met about this and it seems that ‘rick’ and ‘rack’ are interchangable.  The first thing I thought is that originally it was one or the other and as an accident of pronunciation and place of articulation, the alternate version and spelling was adopted.  I haven’t found any actual evidence of this from speaking with employees, but I am holding on to it as a theory for now.  Both the vowel in rick and rack are front vowels produced near the teeth in the front of the mouth, however the one in rack is produced with the mouth more open.  All the other sounds in the words are the same, making these two words a minimal pair in English.  A minimal pair is a set of words where only one sound is different, showing that the two (or more) sounds are distinct (phonemes) in the language.  No sound differences in other parts of the word are influencing the target sound.

The rackhouse has long rows of ricks.  The rick is a large wooden rack that holds the barrels, which sit with the bunghole (where the spirit is poured into the barrel) upward to reduce leaking and drippage.  Some loss of liquid will occur over the years of storage as evaporation and soaking into the barrels occurs naturally.  This lost liquid is known as the Angel’s Share.  Depending on the size and equipment the distillery has, the barrels (weighing around 500 pounds when filled) are rolled or hoisted into the ricks.  Rackhouses are many stories high (I saw them from 4-9 stories) and rely on the differences in temperature and humidity as the seasons change in Kentucky (or anywhere in the U.S. where bourbon is made) to alter the flavor of the spirit in the barrels over years.  Rackhouses may be cooled with pipes that run water through them or by adding or removing the windows to allow air to circulate through the building.

Image: Rackhouse at Jim Beam

Image: Inside a rackhouse at Jim Beam

Image: Looking up inside a rackhouse at Jim Beam

Image: Mila Kunis’ Barrel

Image: Rackhouse at Willett

Image: Inside a rackhouse at Willett, good view of the structure of the ricks as they are not yet stacked with barrels.

Image: These are hams which have been hung in the rackhouse at Willett in hopes they absorb some of the Angel’s Share.

Image: The Bunghole is at the top of the stored barrel to minimize leakage.  You can see the floor is dirt, not uncommon.

Image: The track is used at Willett to roll barrels to the rack house for storage.  Willett is a very small scale craft distillery and much of the production process is still done by hand instead of automation.

The spirit will soak into the oak over time and draw out flavor from the wood and char that has been placed on the barrel.  This aging, in addition to the specific grain bill for the product (which must be at least 51% corn to be called bourbon), creates the aromas and flavors of oak, vanilla, spice, richness, grass, nuttiness, and many others.  Barrels at the top will develop more quickly and those at the bottom, where it is cooler, will need more time. At Jim Beam, barrels are moved and then taken from the house in an X cross pattern to be blended for the bottles.  At Buffalo Trace, and other distilleries, a single barrel is often desired for bottling many of their brands.  These barrels are not blended with others and are drawn from one specific area of the rack house, the “Sweet Spot”.  The Sweet Spot has the distiller’s perfect temperature and humidity to achieve the flavor they want in the signature bourbon of Buffalo Trace, which sits for 9 years before being bottled.

Image: Holly, from Jim Beam Distilling, explaining char.

Image: A rackhouse at Buffalo Trace

Image: Inside one of the rackhouses at Buffalo Trace

image: A rick with barrels at Buffalo Trace

One of the more interesting things about the rackhouses is that each one is different.  This brings us back to aromas. They are built differently, may face the sun differently, the height, windows, and wood may be different.  They have their own character, their own smells, temperatures, airflow, and feel.  Our guide at Buffalo Trace specifically mentioned this as well as talking about a rackhouse that was built and then repurposed as storage because the flavors of the bourbon did not develop in the rackhouse the way they wanted.  Nine years is a long time (and a lot of bourbon) to spend waiting to see if something tastes right, but it is essential to maintain the quality and integrity of the brand.

The different brands under a label (such as Buffalo Trace, Willett, or Jim Beam) come from different rackhouses and different spaces in each one to develop the various flavor notes characteristic of each brand.  Since all bourbon must be aged in oak barrels it is this variation that creates individual character.  Some of the rackhouses were dank and musty like an old basement or garage, some earthy, with the smell of rich soil in the air (tuns out the crawl spaces under the ricks were dirt.  One was funky and sour. Another one was damp, the wood beams of the ricks slighty wet to the touch.  As you walk through the rackhouses you are bombarded with smells as well as the cool feel of the air on your skin; a pleasant change from the July Kentucky sun.

Next time you are out for a walk, or driving to work, or even sitting at home; try for yourself to identify the aromas around you. You might be surprised, as I was, at how well you are able to do this as well as the smells of the things you walk by unnoticed everyday.





To be called Bourbon, a spirit must be:

-made in the United States

-Aged in virgin oak barrels which have been charred inside.  The distiller can choose how much char they want on a scale of 1-5, with every level of char being about 10 seconds of flame exposed to the wood.  Some distilleries, like Woodford Reserve, double char.

-distilled from grain that is at least 51% corn

-distilled to a maximum of 160 proof

-placed in the barrel at a maximum of 125 proof, distillers will use distilled water to bring down the proof for barreling and bottling, to the desired level.

-bottled at a proof of at least 80

There is no minimum time for aging to qualify as bourbon, however anything marked as ‘straight bourbon’ must be aged at least two years.  Straight bourbons may not have color, flavor, or other distilled spirits added, blends/blended bourbon may, but at least 51% must be straight bourbon (Beam Apple and Knob Creek Maple are NOT bourbons.  They started as bourbons, but are no longer so)

Tennessee Whiskey is slightly different; almost all Tennessee whiskeys are in fact, bourbon.  However, they have the additional requirement that they are filtered using the Lincoln County Process.  The LCP requires the spirit to be filtered through maple charcoal before it is barreled. interestingly, the only whiskey that is still produced in (the current) Lincoln County Tennessee is Prichard’s and they do not use the LCP.

I know all about bourbon, now take me back!