DarkRange55
Enlightened
- Oct 15, 2023
- 1,256
Fraley estimates that if she goes through 200 barrelsin a day, she'll find anywhere from one to five honey barrels. "Though sometimes I don't find any!" she adds. "If you're going to find one, they tend to be in an area of the rickhouse that has more southern exposure—areas near windows where it might be warmer, a little hotter." She says, however, that there are no hard and fast rules, and that honey barrels can pretty much pop up anywhere—a mantra echoed by several distillers and blenders, who seem to treat these barrels with a mystical respect.
https://www.whiskyadvocate.com/what-is-a-honey-barrel/
My interpretation has always been that since every barrel will take on a slightly different character and flavor, a honey barrel would be ones they consider the best of the bunch.
Most places do not move barrels around. Consistency comes from batching. Maker's Mark is one of the only distilleries I know which rotates barrels. Honey barrels become honey barrels because they age their entire life in the prime location.
TL;DR an exceptional barrel that may not be representative of the rest of the barrels
There is also a similar concept called a shiny barrel. These are barrels wherein distillery employees have found themselves alone in the rickhouse, and used a straw to liberate some of the fine whiskey inside. Generally their belly will rub off some of the dust and cobwebs that have gathered on the side of the barrel, leading to a shiny looking barrel. The barrel is shiny where shirts and pants have rubbed up against the barrel.
Depending on what kind of whiskey you're considering, it could be over-oaked at 18 years old.
Oak (especially American white oak) is far and away the most common type of wood used for making whiskey. However, it is not the only type used. Occasionally, other woods such as maple, hickory, and a host of others are used for aging whiskey.
People who suggest that whiskey regulations prohibit the use of other woods are not entirely correct. While specific types of whiskey such as Scotch whisky and American bourbon do have such requirements, there are quite a few similar spirits that do not have such specific requirements. For instance, Canadian whiskey, Irish whiskey, and Japanese whiskey only require that wood barrels are used but don't specify that oak is the only permissible type. In many cases, whiskey will be aged in casks formerly used for other types of potables, such as port, madeira, or sauternes. In those cases, the restrictions on the type of wood used will be determined by the rules of the original substance occupying the barrel. In the majority of those instances, the original wines (e.g. port, madeira, or sherry) do require oak as the barrelmaterial, but the qualities of the former contents will affect the flavor of the whiskey along with the wood itself.
Sent from my iPhone
P.S.
There's a couple instances of other barrels being used for tequila - from the top of my head I know some use wine or port barrels - but these are exceptions to the rule.
Madeira is aged in oak, the same as everything else. Normally, it would be a really cool thing to age a spirit in, but used madeira barrels only come from the crappiest young product. True vintage madeira barrels are reused for literally centuries, no producer would ever get rid of one of their real barrels.
The TTB [Alcohol and Tobacco Tax and Trade Bureau] regulation defines bourbon as whiskey "produced in the U.S. at not exceeding 80 percent alcohol by volume (160 proof) from a fermented mash of not less than 51 percent corn and stored at not more than 62.5 percent alcohol by volume (125 proof) in charred new oak containers."
This means that bourbon producers can use French oak, Japanese Mizuna oak, Brazilian oak, Hungarian oak — whatever kind of oak they want, and in whatever kind of container they want, be it a box, a sphere, go crazy — so long as that container is charred and first-use.
You need a hard wood that's durable. So woods like cotton wood and pine are out.
You need a wood that once dried does not seep pitch.
You need a wood that can easily be formed into staves for making barrels. The consistent wood grain of oak keeps it from easily warping at room temperature, but with heat and steam, the staves can be manipulated.
You need a wood that is in good supply. The traditional french oak was widely available when the technology was first developed so the coopers of the time knew how to wok with it.
You need a wood that imparts some flavor, but not too much. That flavor also must be pleasing. This is probably the # 1 reason.
Also, oak is used instead of denser woods like maple because it allows more "breathing." The tighter denser grains of maple don't breath as much as oak, so the wine/whisky doesn't oxidize the same.
There are over 600 species of oak trees in the Quercus genus. The reason for American oak being the most prevalent species used for bourbon is its availability and by extension affordability.
Oak is utilized for its unique physical and chemical nature. Strength and durability, its liquid-tightness, and suitability to coopering. Oak has strength – physically, its wide radial rays give strength when shaped for a cask. The presence of a large volume of medullary rays in the wood structure contribute to this extra strength. The cells of white oak contain tyloses, which are outgrowths on parenchyma cells of the tree's xylem. These cells dam up the vascular tissue, and it is these clogged pores that prevent an oak cask from leaking.
Other woods can leach too many flavors or the particle-density can cause the whiskey to age too quickly. Oak is also a "pure wood," as opposed to pine or rubber trees, which contain resin canals that can pass strong flavors to maturing whisky.
But it's not just the Oak itself, it's the transformation that happens to the Oak as a result of the seasoning and heating treatments during the coopering process. These treatments result in the production of pleasant-tasting Oak lactones.
Whiskey barrels made from Oak have three broad effects on the spirit:
1. As an additive – It adds to the taste and aroma of the spirit by providing desirable elements from the cask. For example: vanillin, Oak lactone (coconut, bourbon character), toastiness, wood sugars and color.
2. As an agent that removes undesirable elements from new make spirit. For example, the charcoal will filter sulphur compounds and immaturity.
3. Oak barrels also interact with the spirit. It adds extractive wood elements from the cask and converts them to organoleptically desirable elements. For example, it will change tannins to acetals, and change acetic acid to fruity esters.
There are 5 specific constituents of Oak that each influence maturing spirits in different ways.
1. Cellulose – Which has virtually no effect other than to hold the wood together.
2. Hemicellulose – Which consists of simple sugars that break down when heated and provide body through the addition of wood sugars for toasty & caramelized aromas & flavors, and color (unaged or "new make" whisky is a clear liquid).
3. Lignin – The binding agent that hold the cellulose in wood together which, when heated yield vanillin, for sweet, smoky and spice aromas.
4. Oak Tannins* – Which play an essential role in maturation by enabling oxidation and the creation of delicate fragrance in spirits. Tannins combine with oxygen and other compounds in the spirit to form acetals over time.
*Naturally occurring preservative compounds with a slightly puckery, astringent taste in the mouth, similar to the effect of strong black tea or fresh walnuts.
5. Oak Lactones – Resulting from lipids in the Oak, they increase dramatically during toasting and charring and can pass on a strong woody and perhaps coconut character. Lactones give Bourbon its distinctive character; and occur in higher concentrations in American Oak than in European varieties.
These white oak barrels give Bourbon 60-70% of their flavor and all of their beautiful amber color.
The three manipulative of stave and barrel creation that impact resulting flavors include, How long you dry the wood outdoors (seasoning), how long you toast, and how long you char.
When you char a barrel, you break down hemicellulose into its ten constituent sugars, which caramelize in a very tight layer underneath the char in existing, unburned wood. And then, as heat radiates and cools, you get the breakdown of lignin into vanillin, and tannic acid begins to turn into the color red. So the heat passes through the barrel and you get different effects. Toasting offers a different impact. If you pre-toast the wood, you can better control your vanillin and your color. You can only char a barrel so long until it burns up. With toasting, the wood is not at risk. You can toast long, short, whatever you want; deep-set your vanillas, deep-set your color, knowing you're going to burn some of that away, but you're going to have plenty as a result of the pre-toast.
Irish oak shows lower density and higher porosity compared to Spanish and American oak, which leads to a more open structure and allows more compounds to be extracted into the spirit and at a faster rate. Irish oak contains higher levels of some lignin derivative compounds, such as vanillin, vanillic acid, and furfural.
Another lesser seen species is Quercus petraea, or sessile oak. French Limousin oak, most commonly used for wine or brandy casks, including Cognac, is Quercus petraea sourced from the Limousin forest.
In Japan, Quercus mongolica, Mongolian oak, or as whisky lovers know it, mizunara oak.
"Mizunara is unique in that it takes from 200 up to 500 years to grow mizunara trees for cask making. Finding trees that match all of these qualities is difficult. "In Japan, mountains are normally steep and there is less flat, wide area, so it is difficult to grow mizunara trees straight. With a long, spicy finish, and flavor notes such as sandalwood, spice, and incense.
Slow growth tends to produce a tighter or more narrow grain, with more rings per inch. Take the flip side [with] Quercus alba; it's generally cut a lot younger, and it's a much faster growing oak. Faster growth leads to a wider grain, with fewer rings per inch, yet increased density, thanks to more cellulose-rich summer wood comparative to spring wood.
Even the same species of oak can showcase divergent characteristics. One factor is region of origin. Obviously oak from the tip of the Cumberlands, say in northern Georgia, Alabama, southern Tennessee, is grown in a warmer climate than oak from up in Minnesota, Wisconsin, where it's a colder climate. Not as much sunshine over the course of the year, so you see growth rings being tighter or broader in that regard. Then you have different soil conditions and rainfall, which have a pattern of tree development.
You also, have to remember the origins of oak barrelsto learn why it is used. Way back in the day most everyone used amphorae to transport wine, beer, spirits. Then the Romans started using a Celtic invention for their wine, the wooden barrel. The wooden barrel was first used for practical reasons. They were lighter than an amphora and could be rolled. The Romans noticed and liked the flavors imparted by the oak. So, ease of use and flavor made them a huge hit. Later they would be used with Scotch and other spirits. Though we have newer technology we still use the barrels, because they are part of the recipe in making whisky/whiskey. Also, don't forget that we started charring the insides of barrels to bring out the more of the wood flavors and add smokiness.
And as far as the shape of the container goes, the barrel is best for ensuring the ideal amount of liquid comes in contact with the wood as the spirit ages and develops its flavor.
Nearly all aged tequila (reposado, anejo, etc.) is aged in ex-bourbon barrels, due to the low price and high availability.
You'll find most whisky in Scotland is aged in used bourbon barrels. It's more cost-effective for the bourbon producers to sell their single-use barrels on and for the malt producers to buy pre-made barrels, and the barrel retains a lot of flavor from its last fill which is desirable. Those whiskies that are finished in Madeira (or Port, sherry, rum, cognac, etc) casks are actually aged in used bourbon barrels for however many years then conditioned in the next barrel for a much shorter period, as little as a few months.
In the early days of bourbon making, Kentucky distillers would package their whiskey in large oak casks to be shipped down the Mississippi River or to the East Coast. The white oak that is still used today was the wood best-suited to making the watertight barrels that were used in shipping. That young distillate would age on its journey, and be bottled at its destination. With a surplus of trees in Kentucky, and the high cost of shipping, there was little impetus to return those used casks to the distillery to be used again, so those trips were generally one-way. This practice may have led to a tradition of using new barrels in later years.
Another reason lies in the chemical reactions that take place between whiskey and barrel. Oak contains several compounds like tannins, lactones, vanillin, and hemicellulose, all of which diffuse into the spirit to lend flavor and color. Because those compounds are poured into bottles along with the whiskey, and drank by eager folks like us, used barrels have less flavoring capacity than new ones (a characteristic Scotch distillers describe as "losing its virtue"). Used barrelsdon't produce spirits with the same level of consistency as a new one, and for big brands like Beam and Sazerac, consistency is critical.
And finally, to be called bourbon in America, a spirit is required by law to be aged in a new barrel. The reasoning behind this law has been the subject of much speculation. Its basis may be an effort to retain part of bourbon's heritage by adhering to the single-use barrel model practiced before Prohibition, or it may be a desire to ensure high quality (much like the Bottled-in-Bond regulations). Or, perhaps more cynically, it may be the result of lobbying from the powerful cooper's union and lumber industry to slide that single, important word ("new") placed in the text of the 1935 Federal Alcohol Administration Act. Or, as if there weren't enough ors already, there's the use of the word new in the current federal regulations which define what exactly bourbon is.
A charred barrel does hold more flavor compounds (like activated charcoal does) but even so, my understanding is that there is a premium for first-reuse barrels.
Some folks actually believe that whiskey oxidizing is actually a myth - because distillation is done at high temperatures any compounds that could have been oxidized should theoretically happen at that stage. Next is barrel aging in a charred barrel (which is the most oxidized form of wood). Due to "angel's share" there's also air present in that barrel during the entire aging process. Alcohol can oxidize...
Different temperatures, humidity and climate variations like proximity to the ocean can produce different secretions from the oak, she adds, and that can also affect the flavor of a finished spirit. This doesn't happen as frequently with rum counterparts in the Caribbean, where temperatures tend to be more stable.
"For me, being at high elevation, one of the things that impacts how the flavor profile develops in a barrel has to do with the penetration of the liquid into the wood."
However, she quickly notes, sheer elevation doesn't do the job alone. It also impacts temperature, barometric pressure and humidity. The pores of the wood expand and contract with heat and cold, pulling the rum in and out of the oak and giving it more contact with the barrel, which helps flavors to develop more quickly. This kinetic action is a form of dynamic aging, Hoskin explains. Some spirits makers try to mimic the effect by agitating barrels to increase contact between the liquid and the wood.
"Sometimes, at sea level, you put rum into a barreland you and absorb a certain amount of rum into the barrel, and doesn't change after that," says Hoskin. "There's not a lot of kinetic action."
Q. Do you think its real or just a marketing gimmick/novelty?
A. Some effect - temperature certainly, probably also humidity, maybe even altitude. Changes in pressure might slightly flex the barrel, or pull liquid into pores and push it out again ... maybe...
https://www.winemag.com/2021/12/28/spirits-age-elevation-whiskey-rum/
Did calculations for sphere cube and cylinder with a constant volume of 256. Tried it with cubic ones, short fat ones, tall skinny ones all the same: They have the exact same ratio of wall material to liquid stored. Hexagon (hexagonal cylinder) uses more material. But they would stack perfectly. (Least material per volume when stacked. You fit more barrels/cells in a given confined space. So stacking. Hexagon uses less material than cylinders in the context of honeycomb where gaps between would be filled in. If they were to make it circular they would have to fill in the gaps with wax using a hell of a lot more wax. Bees could use triangles or squares for storage. Those wouldn't leave gaps. Cubes also stack perfectly. Hexagons not only stack perfectly they are also a very strong shape. It's a balance of stacking efficiency and strength. Squares stack efficiently but aren't strong, cylinders are strong but stack poorly. Hexagons are also equally strong in all directions. Cubes would only be strong in two directions. So hexagon is the perfect balance of material used to strength. Allowing the least amount of material to be used to hold the most weight (honey and larvae) when they are stacked in such a fashion). You could fit many more hexagonal barrels in a warehouse as they stack more efficiently. A cylindrical barrel would be way stronger than a cube. A spherical barrel would be hard to produce. A hexagon wouldn't be as strong either. It's the tapering, it creates an arch. And in the case of whiskey I think they want more airflow. You would need airflow to keep the barrels at a consistent temperature. Otherwise the barrels in the middle of a giant stack would never get exposed to the outside temperature but the barrels on the exterior of the stack would resulting in very different aging between barrels.
So in an ideal world where you don't have to worry about waste when manufacturing or exterior bracing or difficulty manufacturing. The sphere uses the least material. Cube and cylinder are the same in that ideal world. Real world I think cylinder. But each barreluses more wood for the same volume. Sphere is best, followed by cube and cylinder equally, followed by hexagon in minimizing wall material to liquid stored. Cube and cylinder exactly the same. Ignoring the extra supports that would be needed to make the cube strong enough. The sphere would age the slowest. Less wood surface area to volume. More liquid per square inch of wood. Smaller barrels also age faster. More wood to liquid = faster aging. Larger barrels = less liquid to wood resulting in longer aging but less wood used. So it's a trade off. Then not being able to roll it. Before fork lifts this is probably a huge deal. It still probably is easier to be able to roll them.
This article explains it:
https://thewhiskeywash.com/whiskey-science/cask-geometry-plays-significant-role-whiskey-aging/
https://askdruniverse.wsu.edu/2015/11/02/why-do-bees-make-hexagons/
https://www.spiritedbiz.com/turning-up-the-heat-climates-affect-on-aging-spirits-part-1/
So barrels are used due to the strength of construction, minimize wood used for volume, ease of transport, (I also don't think they don't want to stack too close so they have better consistent climate control).
There there are only three geometrical figures with equal sides that can fit together on a flat surface without leaving gaps: equilateral triangles, squares and hexagons. The honeycomb conjecture states that a regular hexagonal grid or honeycomb is the best way to divide a surface into regions of equal area with the least total perimeter. The conjecture was proven in 1999 by mathematician Thomas C. Hales.
Undersea aging of wines & also aging bourbon barrels on moving ships. I have attached some screen shots of the crux of their claims. The main points seem to be: constant motion, darkness, lack of O2, pressure difference & temperature. The bourbon aging actually seems to make sense since the increased sloshing from ocean movement might increase surface-area contact between the barrels and bourbon.
Pressure. The wines are subjected to a
pressure of 3 bars (3 atm). This causes that
oxygen partial pressure inside the bottle
changes, and is greater inside than outside
Together with the lower gravity facilitate the
processes for the different evolution of the wine
Movement. The constant rocking of currents
tides and waves make that our underwater wines
do not rest, they sway, and they evolve at the
constant rate of marine movement.
Gravity. Under the sea the weights of objects
are less. The same happens with liquids, so the
wine is subjected to a greater pressure that
affects its structure.
Tides Every six hours the sea rises or falls up
to 4 meters high, without stopping. This is one of
the effects of the moon We have extreme
biodynamic wines. These strong tides increase
or decrease the pressure on the wines, ma
them "breathe more or less every six hours.
"It's better than even the best
underground cellar, especially for sparkling
wine. The temperature is perfect, there's no
light, the water prevents even the slightest bit of
air from getting in, and the constant
counterpressure keeps the bubbles bubbly
Moreover the underwater currents act like a
crib, gently rocking the bottles and keeping the
lees moving through the wine." (The lees refer
to yeast particles.)
"They have a constant pressure and movement and stability of temperature, so they are moving with the ocean and, doing that, their metabolism, their habits, are very different so they create strange aromas ocean aromas." he said, describing the process.
Chemist Tom Collins, a researcher at the University
of California, Davis, who has analyzed the flavor
profiles of American whiskeys, says higher
temperatures like those found in tropical locales, and the swill of the ocean, can both accelerate the
whiskey aging process. "The daily swing in temperature matters," Collins explains. "As the liquid warms up, it expands into the wood. And then as it cools down, it contracts, which can improve extraction" of compounds from the wood -compounds that give aged whiskey its characteristic flavor. "These reactions are generally
favored with higher temperatures." And greater extraction, Collins says, results in more caramel-related compounds, altering the flavor and
color of bourbon. After his initial revelation, Zoeller sent five barrels of recently distilled bourbon out to sea with Chris Fischer. A high school friend of Zoeller's, Fischer heads OCEARCH, an organization that tracks sharks and other endangered marine life. He kept the barrels on board his ship for three and a half years. Fischer covered more than 10,000 nautical miles, traveling south of the equator and in and out of the Panama Canal six times.
"The experiment totally exceeded our expectations
he says, "The bourbon went in clear as water and
came out black. Bourbon always picks up color in the barrel, but this 4-vear-old bourbon was darker than 30-year-old bourbon. And the salt air gave the bourbon a briny taste more similar to an Irish single malt - and coloring like dark rum, Zoeller savs.
The unique combination fulled a buying frenzy
among bourbon enthusiasts. Some paid much as a thousand dollars at auction for a bottle 8800 more than the original selling price. Since those first barrelswere shipped out, Zoeller has aged two more generations of his Jefferson's Ocean bourbon on the high seas for roughly three to four years at a time, varying their routes to more than 40 ports - as far north as Scandinavia and south to Africa's Cape of Good Hope. Each batch returns with a different flavor and color.
A mix, but mostly hype. For example in the second screenshot the tides and gravity explanations are nonsense. The first screenshot also praises stable temperature, while the third screenshot indicates that temperature swings are useful. As for the other conditions, they are physically valid but could be reproduced on land.
I agree on a single barrel – it is mostly psychological. When I tap more than one maple tree, I separate the sap by tree just because I can, and there is a slight difference in flavor.
https://www.whiskyadvocate.com/what-is-a-honey-barrel/
My interpretation has always been that since every barrel will take on a slightly different character and flavor, a honey barrel would be ones they consider the best of the bunch.
Most places do not move barrels around. Consistency comes from batching. Maker's Mark is one of the only distilleries I know which rotates barrels. Honey barrels become honey barrels because they age their entire life in the prime location.
TL;DR an exceptional barrel that may not be representative of the rest of the barrels
There is also a similar concept called a shiny barrel. These are barrels wherein distillery employees have found themselves alone in the rickhouse, and used a straw to liberate some of the fine whiskey inside. Generally their belly will rub off some of the dust and cobwebs that have gathered on the side of the barrel, leading to a shiny looking barrel. The barrel is shiny where shirts and pants have rubbed up against the barrel.
Depending on what kind of whiskey you're considering, it could be over-oaked at 18 years old.
Oak (especially American white oak) is far and away the most common type of wood used for making whiskey. However, it is not the only type used. Occasionally, other woods such as maple, hickory, and a host of others are used for aging whiskey.
People who suggest that whiskey regulations prohibit the use of other woods are not entirely correct. While specific types of whiskey such as Scotch whisky and American bourbon do have such requirements, there are quite a few similar spirits that do not have such specific requirements. For instance, Canadian whiskey, Irish whiskey, and Japanese whiskey only require that wood barrels are used but don't specify that oak is the only permissible type. In many cases, whiskey will be aged in casks formerly used for other types of potables, such as port, madeira, or sauternes. In those cases, the restrictions on the type of wood used will be determined by the rules of the original substance occupying the barrel. In the majority of those instances, the original wines (e.g. port, madeira, or sherry) do require oak as the barrelmaterial, but the qualities of the former contents will affect the flavor of the whiskey along with the wood itself.
Sent from my iPhone
P.S.
There's a couple instances of other barrels being used for tequila - from the top of my head I know some use wine or port barrels - but these are exceptions to the rule.
Madeira is aged in oak, the same as everything else. Normally, it would be a really cool thing to age a spirit in, but used madeira barrels only come from the crappiest young product. True vintage madeira barrels are reused for literally centuries, no producer would ever get rid of one of their real barrels.
The TTB [Alcohol and Tobacco Tax and Trade Bureau] regulation defines bourbon as whiskey "produced in the U.S. at not exceeding 80 percent alcohol by volume (160 proof) from a fermented mash of not less than 51 percent corn and stored at not more than 62.5 percent alcohol by volume (125 proof) in charred new oak containers."
This means that bourbon producers can use French oak, Japanese Mizuna oak, Brazilian oak, Hungarian oak — whatever kind of oak they want, and in whatever kind of container they want, be it a box, a sphere, go crazy — so long as that container is charred and first-use.
You need a hard wood that's durable. So woods like cotton wood and pine are out.
You need a wood that once dried does not seep pitch.
You need a wood that can easily be formed into staves for making barrels. The consistent wood grain of oak keeps it from easily warping at room temperature, but with heat and steam, the staves can be manipulated.
You need a wood that is in good supply. The traditional french oak was widely available when the technology was first developed so the coopers of the time knew how to wok with it.
You need a wood that imparts some flavor, but not too much. That flavor also must be pleasing. This is probably the # 1 reason.
Also, oak is used instead of denser woods like maple because it allows more "breathing." The tighter denser grains of maple don't breath as much as oak, so the wine/whisky doesn't oxidize the same.
There are over 600 species of oak trees in the Quercus genus. The reason for American oak being the most prevalent species used for bourbon is its availability and by extension affordability.
Oak is utilized for its unique physical and chemical nature. Strength and durability, its liquid-tightness, and suitability to coopering. Oak has strength – physically, its wide radial rays give strength when shaped for a cask. The presence of a large volume of medullary rays in the wood structure contribute to this extra strength. The cells of white oak contain tyloses, which are outgrowths on parenchyma cells of the tree's xylem. These cells dam up the vascular tissue, and it is these clogged pores that prevent an oak cask from leaking.
Other woods can leach too many flavors or the particle-density can cause the whiskey to age too quickly. Oak is also a "pure wood," as opposed to pine or rubber trees, which contain resin canals that can pass strong flavors to maturing whisky.
But it's not just the Oak itself, it's the transformation that happens to the Oak as a result of the seasoning and heating treatments during the coopering process. These treatments result in the production of pleasant-tasting Oak lactones.
Whiskey barrels made from Oak have three broad effects on the spirit:
1. As an additive – It adds to the taste and aroma of the spirit by providing desirable elements from the cask. For example: vanillin, Oak lactone (coconut, bourbon character), toastiness, wood sugars and color.
2. As an agent that removes undesirable elements from new make spirit. For example, the charcoal will filter sulphur compounds and immaturity.
3. Oak barrels also interact with the spirit. It adds extractive wood elements from the cask and converts them to organoleptically desirable elements. For example, it will change tannins to acetals, and change acetic acid to fruity esters.
There are 5 specific constituents of Oak that each influence maturing spirits in different ways.
1. Cellulose – Which has virtually no effect other than to hold the wood together.
2. Hemicellulose – Which consists of simple sugars that break down when heated and provide body through the addition of wood sugars for toasty & caramelized aromas & flavors, and color (unaged or "new make" whisky is a clear liquid).
3. Lignin – The binding agent that hold the cellulose in wood together which, when heated yield vanillin, for sweet, smoky and spice aromas.
4. Oak Tannins* – Which play an essential role in maturation by enabling oxidation and the creation of delicate fragrance in spirits. Tannins combine with oxygen and other compounds in the spirit to form acetals over time.
*Naturally occurring preservative compounds with a slightly puckery, astringent taste in the mouth, similar to the effect of strong black tea or fresh walnuts.
5. Oak Lactones – Resulting from lipids in the Oak, they increase dramatically during toasting and charring and can pass on a strong woody and perhaps coconut character. Lactones give Bourbon its distinctive character; and occur in higher concentrations in American Oak than in European varieties.
These white oak barrels give Bourbon 60-70% of their flavor and all of their beautiful amber color.
The three manipulative of stave and barrel creation that impact resulting flavors include, How long you dry the wood outdoors (seasoning), how long you toast, and how long you char.
When you char a barrel, you break down hemicellulose into its ten constituent sugars, which caramelize in a very tight layer underneath the char in existing, unburned wood. And then, as heat radiates and cools, you get the breakdown of lignin into vanillin, and tannic acid begins to turn into the color red. So the heat passes through the barrel and you get different effects. Toasting offers a different impact. If you pre-toast the wood, you can better control your vanillin and your color. You can only char a barrel so long until it burns up. With toasting, the wood is not at risk. You can toast long, short, whatever you want; deep-set your vanillas, deep-set your color, knowing you're going to burn some of that away, but you're going to have plenty as a result of the pre-toast.
Irish oak shows lower density and higher porosity compared to Spanish and American oak, which leads to a more open structure and allows more compounds to be extracted into the spirit and at a faster rate. Irish oak contains higher levels of some lignin derivative compounds, such as vanillin, vanillic acid, and furfural.
Another lesser seen species is Quercus petraea, or sessile oak. French Limousin oak, most commonly used for wine or brandy casks, including Cognac, is Quercus petraea sourced from the Limousin forest.
In Japan, Quercus mongolica, Mongolian oak, or as whisky lovers know it, mizunara oak.
"Mizunara is unique in that it takes from 200 up to 500 years to grow mizunara trees for cask making. Finding trees that match all of these qualities is difficult. "In Japan, mountains are normally steep and there is less flat, wide area, so it is difficult to grow mizunara trees straight. With a long, spicy finish, and flavor notes such as sandalwood, spice, and incense.
Slow growth tends to produce a tighter or more narrow grain, with more rings per inch. Take the flip side [with] Quercus alba; it's generally cut a lot younger, and it's a much faster growing oak. Faster growth leads to a wider grain, with fewer rings per inch, yet increased density, thanks to more cellulose-rich summer wood comparative to spring wood.
Even the same species of oak can showcase divergent characteristics. One factor is region of origin. Obviously oak from the tip of the Cumberlands, say in northern Georgia, Alabama, southern Tennessee, is grown in a warmer climate than oak from up in Minnesota, Wisconsin, where it's a colder climate. Not as much sunshine over the course of the year, so you see growth rings being tighter or broader in that regard. Then you have different soil conditions and rainfall, which have a pattern of tree development.
You also, have to remember the origins of oak barrelsto learn why it is used. Way back in the day most everyone used amphorae to transport wine, beer, spirits. Then the Romans started using a Celtic invention for their wine, the wooden barrel. The wooden barrel was first used for practical reasons. They were lighter than an amphora and could be rolled. The Romans noticed and liked the flavors imparted by the oak. So, ease of use and flavor made them a huge hit. Later they would be used with Scotch and other spirits. Though we have newer technology we still use the barrels, because they are part of the recipe in making whisky/whiskey. Also, don't forget that we started charring the insides of barrels to bring out the more of the wood flavors and add smokiness.
And as far as the shape of the container goes, the barrel is best for ensuring the ideal amount of liquid comes in contact with the wood as the spirit ages and develops its flavor.
Nearly all aged tequila (reposado, anejo, etc.) is aged in ex-bourbon barrels, due to the low price and high availability.
You'll find most whisky in Scotland is aged in used bourbon barrels. It's more cost-effective for the bourbon producers to sell their single-use barrels on and for the malt producers to buy pre-made barrels, and the barrel retains a lot of flavor from its last fill which is desirable. Those whiskies that are finished in Madeira (or Port, sherry, rum, cognac, etc) casks are actually aged in used bourbon barrels for however many years then conditioned in the next barrel for a much shorter period, as little as a few months.
In the early days of bourbon making, Kentucky distillers would package their whiskey in large oak casks to be shipped down the Mississippi River or to the East Coast. The white oak that is still used today was the wood best-suited to making the watertight barrels that were used in shipping. That young distillate would age on its journey, and be bottled at its destination. With a surplus of trees in Kentucky, and the high cost of shipping, there was little impetus to return those used casks to the distillery to be used again, so those trips were generally one-way. This practice may have led to a tradition of using new barrels in later years.
Another reason lies in the chemical reactions that take place between whiskey and barrel. Oak contains several compounds like tannins, lactones, vanillin, and hemicellulose, all of which diffuse into the spirit to lend flavor and color. Because those compounds are poured into bottles along with the whiskey, and drank by eager folks like us, used barrels have less flavoring capacity than new ones (a characteristic Scotch distillers describe as "losing its virtue"). Used barrelsdon't produce spirits with the same level of consistency as a new one, and for big brands like Beam and Sazerac, consistency is critical.
And finally, to be called bourbon in America, a spirit is required by law to be aged in a new barrel. The reasoning behind this law has been the subject of much speculation. Its basis may be an effort to retain part of bourbon's heritage by adhering to the single-use barrel model practiced before Prohibition, or it may be a desire to ensure high quality (much like the Bottled-in-Bond regulations). Or, perhaps more cynically, it may be the result of lobbying from the powerful cooper's union and lumber industry to slide that single, important word ("new") placed in the text of the 1935 Federal Alcohol Administration Act. Or, as if there weren't enough ors already, there's the use of the word new in the current federal regulations which define what exactly bourbon is.
A charred barrel does hold more flavor compounds (like activated charcoal does) but even so, my understanding is that there is a premium for first-reuse barrels.
Some folks actually believe that whiskey oxidizing is actually a myth - because distillation is done at high temperatures any compounds that could have been oxidized should theoretically happen at that stage. Next is barrel aging in a charred barrel (which is the most oxidized form of wood). Due to "angel's share" there's also air present in that barrel during the entire aging process. Alcohol can oxidize...
Different temperatures, humidity and climate variations like proximity to the ocean can produce different secretions from the oak, she adds, and that can also affect the flavor of a finished spirit. This doesn't happen as frequently with rum counterparts in the Caribbean, where temperatures tend to be more stable.
"For me, being at high elevation, one of the things that impacts how the flavor profile develops in a barrel has to do with the penetration of the liquid into the wood."
However, she quickly notes, sheer elevation doesn't do the job alone. It also impacts temperature, barometric pressure and humidity. The pores of the wood expand and contract with heat and cold, pulling the rum in and out of the oak and giving it more contact with the barrel, which helps flavors to develop more quickly. This kinetic action is a form of dynamic aging, Hoskin explains. Some spirits makers try to mimic the effect by agitating barrels to increase contact between the liquid and the wood.
"Sometimes, at sea level, you put rum into a barreland you and absorb a certain amount of rum into the barrel, and doesn't change after that," says Hoskin. "There's not a lot of kinetic action."
Q. Do you think its real or just a marketing gimmick/novelty?
A. Some effect - temperature certainly, probably also humidity, maybe even altitude. Changes in pressure might slightly flex the barrel, or pull liquid into pores and push it out again ... maybe...
https://www.winemag.com/2021/12/28/spirits-age-elevation-whiskey-rum/
Did calculations for sphere cube and cylinder with a constant volume of 256. Tried it with cubic ones, short fat ones, tall skinny ones all the same: They have the exact same ratio of wall material to liquid stored. Hexagon (hexagonal cylinder) uses more material. But they would stack perfectly. (Least material per volume when stacked. You fit more barrels/cells in a given confined space. So stacking. Hexagon uses less material than cylinders in the context of honeycomb where gaps between would be filled in. If they were to make it circular they would have to fill in the gaps with wax using a hell of a lot more wax. Bees could use triangles or squares for storage. Those wouldn't leave gaps. Cubes also stack perfectly. Hexagons not only stack perfectly they are also a very strong shape. It's a balance of stacking efficiency and strength. Squares stack efficiently but aren't strong, cylinders are strong but stack poorly. Hexagons are also equally strong in all directions. Cubes would only be strong in two directions. So hexagon is the perfect balance of material used to strength. Allowing the least amount of material to be used to hold the most weight (honey and larvae) when they are stacked in such a fashion). You could fit many more hexagonal barrels in a warehouse as they stack more efficiently. A cylindrical barrel would be way stronger than a cube. A spherical barrel would be hard to produce. A hexagon wouldn't be as strong either. It's the tapering, it creates an arch. And in the case of whiskey I think they want more airflow. You would need airflow to keep the barrels at a consistent temperature. Otherwise the barrels in the middle of a giant stack would never get exposed to the outside temperature but the barrels on the exterior of the stack would resulting in very different aging between barrels.
So in an ideal world where you don't have to worry about waste when manufacturing or exterior bracing or difficulty manufacturing. The sphere uses the least material. Cube and cylinder are the same in that ideal world. Real world I think cylinder. But each barreluses more wood for the same volume. Sphere is best, followed by cube and cylinder equally, followed by hexagon in minimizing wall material to liquid stored. Cube and cylinder exactly the same. Ignoring the extra supports that would be needed to make the cube strong enough. The sphere would age the slowest. Less wood surface area to volume. More liquid per square inch of wood. Smaller barrels also age faster. More wood to liquid = faster aging. Larger barrels = less liquid to wood resulting in longer aging but less wood used. So it's a trade off. Then not being able to roll it. Before fork lifts this is probably a huge deal. It still probably is easier to be able to roll them.
This article explains it:
https://thewhiskeywash.com/whiskey-science/cask-geometry-plays-significant-role-whiskey-aging/
https://askdruniverse.wsu.edu/2015/11/02/why-do-bees-make-hexagons/
https://www.spiritedbiz.com/turning-up-the-heat-climates-affect-on-aging-spirits-part-1/
So barrels are used due to the strength of construction, minimize wood used for volume, ease of transport, (I also don't think they don't want to stack too close so they have better consistent climate control).
There there are only three geometrical figures with equal sides that can fit together on a flat surface without leaving gaps: equilateral triangles, squares and hexagons. The honeycomb conjecture states that a regular hexagonal grid or honeycomb is the best way to divide a surface into regions of equal area with the least total perimeter. The conjecture was proven in 1999 by mathematician Thomas C. Hales.
Undersea aging of wines & also aging bourbon barrels on moving ships. I have attached some screen shots of the crux of their claims. The main points seem to be: constant motion, darkness, lack of O2, pressure difference & temperature. The bourbon aging actually seems to make sense since the increased sloshing from ocean movement might increase surface-area contact between the barrels and bourbon.
Pressure. The wines are subjected to a
pressure of 3 bars (3 atm). This causes that
oxygen partial pressure inside the bottle
changes, and is greater inside than outside
Together with the lower gravity facilitate the
processes for the different evolution of the wine
Movement. The constant rocking of currents
tides and waves make that our underwater wines
do not rest, they sway, and they evolve at the
constant rate of marine movement.
Gravity. Under the sea the weights of objects
are less. The same happens with liquids, so the
wine is subjected to a greater pressure that
affects its structure.
Tides Every six hours the sea rises or falls up
to 4 meters high, without stopping. This is one of
the effects of the moon We have extreme
biodynamic wines. These strong tides increase
or decrease the pressure on the wines, ma
them "breathe more or less every six hours.
"It's better than even the best
underground cellar, especially for sparkling
wine. The temperature is perfect, there's no
light, the water prevents even the slightest bit of
air from getting in, and the constant
counterpressure keeps the bubbles bubbly
Moreover the underwater currents act like a
crib, gently rocking the bottles and keeping the
lees moving through the wine." (The lees refer
to yeast particles.)
"They have a constant pressure and movement and stability of temperature, so they are moving with the ocean and, doing that, their metabolism, their habits, are very different so they create strange aromas ocean aromas." he said, describing the process.
Chemist Tom Collins, a researcher at the University
of California, Davis, who has analyzed the flavor
profiles of American whiskeys, says higher
temperatures like those found in tropical locales, and the swill of the ocean, can both accelerate the
whiskey aging process. "The daily swing in temperature matters," Collins explains. "As the liquid warms up, it expands into the wood. And then as it cools down, it contracts, which can improve extraction" of compounds from the wood -compounds that give aged whiskey its characteristic flavor. "These reactions are generally
favored with higher temperatures." And greater extraction, Collins says, results in more caramel-related compounds, altering the flavor and
color of bourbon. After his initial revelation, Zoeller sent five barrels of recently distilled bourbon out to sea with Chris Fischer. A high school friend of Zoeller's, Fischer heads OCEARCH, an organization that tracks sharks and other endangered marine life. He kept the barrels on board his ship for three and a half years. Fischer covered more than 10,000 nautical miles, traveling south of the equator and in and out of the Panama Canal six times.
"The experiment totally exceeded our expectations
he says, "The bourbon went in clear as water and
came out black. Bourbon always picks up color in the barrel, but this 4-vear-old bourbon was darker than 30-year-old bourbon. And the salt air gave the bourbon a briny taste more similar to an Irish single malt - and coloring like dark rum, Zoeller savs.
The unique combination fulled a buying frenzy
among bourbon enthusiasts. Some paid much as a thousand dollars at auction for a bottle 8800 more than the original selling price. Since those first barrelswere shipped out, Zoeller has aged two more generations of his Jefferson's Ocean bourbon on the high seas for roughly three to four years at a time, varying their routes to more than 40 ports - as far north as Scandinavia and south to Africa's Cape of Good Hope. Each batch returns with a different flavor and color.
A mix, but mostly hype. For example in the second screenshot the tides and gravity explanations are nonsense. The first screenshot also praises stable temperature, while the third screenshot indicates that temperature swings are useful. As for the other conditions, they are physically valid but could be reproduced on land.
I agree on a single barrel – it is mostly psychological. When I tap more than one maple tree, I separate the sap by tree just because I can, and there is a slight difference in flavor.
