Here are pictures of the iStill Fermenter 2000 that we have built for a UK distillery. Like all of our fermenters, it comes equipped with agitator, temperature control, pH control, and SG control. Why? Because if we help the craft distiller control their fermentations, we help them control the consistent production of both alcohol and flavor composition!
We decided to make the practical training, that follows-up on the online iStill Distilling University, a one-on-one experience. One-on-one as in “one distillery at a time”. At iStill HQ. Where you make your recipe on a set-up similar to the one you purchased. Supervised by an iStill Master Distiller. The goal? To help increase your operational competence.
Machine Learning for iStill Customers
With a wink to our machines being pretty advanced, we call it “Machine Learning”. But it isn’t about the still learning new tricks. No, instead the new customer learns how to make his exact recipe on the new iStill equipment they purchased, exactly configured the way you ordered it.
Create operational competence!
Group-training is a great way to teach all of the participants the same thing. But if we want to help new customers gain more operational experience faster, we strongly feel that training should be perfectly tailored to the spirit they want to make, given the machinery they want to use. A more specialized educational experience generates more operational expertise, specific to your distillery, to your spirits, to the flavor profile you want to highlight, and to the distiller you want to be.
Since gaining operational competence is based on passion, the willingness to learn, and on the wish to own all the processes related to running a craft distillery, iStill’s Machine Learning Program is not open-ended. Instead, we ask for your commitment, resulting in you coming to the party well-prepared. If that doesn’t make sense, please read:
Two Types of Machine Learning Programs
We foresee two types of Machine Learning Programs. The first one centers around the craft distiller making their own alcohol via mashing and fermenting and distilling. The second one centers on the craft distiller redistilling GNS with herbs.
“Distilled Machine Learning” is for those that want to make brandy, rum, or whiskey. “Redistilled Machine learning” trains our customers in making gin, akvavit, or liqueur. The first variety takes eight days, the second one only three. Both take place at iStill HQ in the Netherlands. The goal is that you become competent in distilling your recipe on your iStill configuration.
On the “Distilled Machine Learning”, the following is included:
- Assemble your iStill;
- Update your iStill;
- Test your iStill;
- Cleaning run;
- Mashing with your iStill Distillery;
- Fermenting with your iStill Distillery;
- Distilling with your iStill Distillery;
- Cleaning the iStill after a run;
- Certified Master Distilled Diploma.
You will assemble your iStill (or a similar model), update it to the newest software, and test the unit on the first day. Mashing will take place on the second day. Fermentation takes place on days three through six. You will distill your brandy, rum, or whiskey on the seventh day. You will clean the iStill on the last day. The entire process will be monitored and supervised by an experienced iStill master distiller.
On the “Redistilled Machine Learning Program”, the following is included:
- Assemble your iStill;
- Update your iStill;
- Test your iStill;
- Cleaning run;
- Distilling with your iStill;
- Cleaning the iStill after a run;
- Certified Master Distilled Diploma.
You will assemble your iStill (or a similar model), update it to the newest software, and test the unit on the first day. Distilling will take place on the second day. You will clean the iStill on the third and last day. The entire process will be monitored and supervised by an experienced iStill master distiller.
For whom is it?
For new or existing iStill customers or distillers, that want to gain operational competence in making one certain recipe. One distillery will be trained at a time, to do justice to your unique product, SOP, wishes, and equipment make-up. The maximum number of participants from your distillery is three. You can decide to send one, two, or three students, as long as they all certified for our online Distilling University (so we all speak the same language).
Your Machine Learning Program will be planned after the following criteria are met:
- The Machine Learning Program is paid for;
- You graduated from the online iStill Distilling University;
- We received your recipe;
- And the yeasts, herbs, substrates, or grains that go with it;
- We received your SOP.
How to order and what it costs?
New customers can add the Distilled or Redistilled Machine Learning Programs as options to their iStill purchase orders. Existing customers can send an email to Esther@iStillmail.com. The eight day Distilled Machine Learning Program costs EUR 10.000,-. The three day Redistilled Machine Learning Program is EUR 5.000,-. For that price, you can send one, two, or three participants.
Machine learning is about the distiller …
We are proud to announce that the iStill Distilling University curriculum is now available online. All of it. We are feature complete!
When we started the iStill Distilling University, now some five years ago, our goal was to teach and train our students in the real science of distillation. By focussing on toolkits and recipe development in combination with hands-on distilling, the iStill Distilling University soon became the best educational facility in the craft distilling industry. Students rate the experience with a 9.8 out of 10!
Covid-19 has hampered our ability to give courses and trainings via live events with students participating physically. So, a few months ago we decided to see if we could put the content and many of the more practical exercises online. Today, we are proud to announce that all the basic information is now uploaded, for you to enjoy.
The base course consists of 23 (!) series of movies, teaching topics like gin making, vodka, still design, rum, whiskey, brandy, flavor profiling, Odin’s theories of fermentation and distillation, and much, much more. Every series is concluded with a multiple-choice exam. If you pass all exams, you are eligible for certification and iStill University Facebook group admittance. The certificate is proof of the student being a craft distiller. The Facebook group is a great place to meet other distillers and exchange information and experiences.
So, wow, yeah, we are ready, right? Job well done and off to the next project? No, not really. We want the iStill Distilling University Online to be about continuous education. The base curriculum is now online, but let’s keep adding info. The Livestream on how to make orange gin, for example, would make a great addition. And we have started interviewing craft distillers from around the globe on their passion, their business models, and more. We’ll start adding those as well.
As far as we are concerned, the iStill Distilling University Online will always be open, will always be there as a source for continued education. But what will we speak about? What topics would you like us to tackle? Please see the poll underneath and let us know what you prefer us to focus on:
The iStill Distilling University has established itself, in the five years since its introduction, as the craft distilling industry’s leading educational facility. Over 200 students participated at the courses that the iStill Distilling University provided annually and students rate the curriculum with an astonishing 9.8 on a 10-point scale.
The way the iStill Distilling University was set-up was via courses that took place in groups and that dealt with theory as well as practice. Students would learn how to mash, and ferment, and distill, and then put that into practice at iStill HQ, where the iStill Distilling University resides.
A deeper learning experience
Based on our experience and your feedback, we have now reorganized the way the iStill Distilling University is set-up. The goal? To turn an astonishing experience in an even better one! To take your learning and training to the next level. To cater to your needs, if you want to become the best distiller you can be, making the best spirits possible, and winning medals while making them.
In short, from now onwards, the Distilling University will replace the “one size fits all” with a more tailor-made make-up. From now onwards, the iStill Distilling University will offer three levels of training and learning, three levels of participation:
- Craft Distiller;
- Master Distiller.
Distiller (level 1)
People interested in distilling can register at the iStill University Online for free. They get access to all the articles of the iStill Blog, arguably the world’s biggest library of distillation information. Subscription to the eNewsletter “Distillers Weekly” is also included. And you get access to three free movies from the Certified Craft Distiller Course.
This base level entry into the Distilling University keeps anyone interested in craft distilling up to date on what’s happening in the industry. This entry level is a great way to start learning about distilling. The information shared is based on facts and science, rather than anecdotical story-telling and make-belief.
Certified Craft Distiller (level 2)
Do you want to become a craft distiller? Then the second layer of training and learning that the iStill Distilling University offers will serve you just fine. This second level offers you an online learning environment with dozens of instructional video’s that teach you all about craft distilling. The instructional video’s are complimented with practical video’s that show you how to make gin, vodka, brandy, rum, whiskey, and liqueurs. Q&A-sessions further deepen the training of your capabilities and understanding.
The online training can be purchased on its own, but it is advised to include the iStill Mini in the purchase. That way you can train yourself on executing the theories presented, and you can start developing your skills as well as your recipes.
The Certified Craft Distiller Course is home-schooling or self-training. No need to fly over to the Netherlands. It comes with an exam. Successful participation and graduation results in the student becoming a Certified Craft Distiller.
The Certified Craft Distiller Course costs EUR 2.000,-. The iStill Mini is (with transport and trolley bag) EUR 3.500,-. Buy them together for the package deal of EUR 5.000,-. For more information, please see: https://istill.com/mini
Certified Master Distiller (3)
For those that want to dive in deeper, we now have added a new, 4-day additional course, that takes place at iStill HQ and where you will receive hands-on training in small groups. Using the iStill 10, 50 and 100, you will mash, ferment, and distill and perfect your recipes with our guidance.
We’ll also extensively train you on flavor recognition, since that is the strongest tool distillers have to interpret how a drink was made, how any faults can be identified and resolved, and how the world’s best spirits can be designed and produced.
The successful participation and graduation results in the student becoming a Certified Master Distiller. In order to participate, the student must already be a Certified Craft Distiller. The Certified Master Distiller Course costs EUR 3.000,- and takes place at iStill HQ in the Netherlands. All lunches and dinners are included (in fact the dinners will be part of the training, focussing on spirits tasting and food and cocktail pairing).
For more information and registration, please reach out to Veronika@iStillmail.com.
Layers of learning …
The iStill Distilling University releases new videos on a weekly basis. This week a new video series got released that explains Odin’s amazing theory of fermentation. Fermentation as in where you create your spirits’ alcohol and flavor molecules. And the first movie in that series seems to be unlocked and free to watch … Wanna learn all about fermenting?
Go check it out via: https://istill.com/university
On the iStills 500, 1000, 2000, and 5000, the pre-cooler now comes as standard equipment. On the Potstills, Plates Stills, and Hybrid iStills of those sizes.
The pre-cooler takes the load of the main cooler and improves overall cooling efficiency. The same amount of coolant leads to better cooling. Ideal in warmer climates. Or, by running the pre-cooler and the column cooler from different water lines, one can increase the total amount of coolant used, making cooling more effective.
Nota bene! Distilling is about heating up liquids to the point where they boil and create gasses. And distilling is just as much about cooling those gasses down to liquid phase again. In other words, given the iStill’s efficiency, power in basically equals cooling in.
The pre-cooler is no excuse not to invest in a professional sized chiller that provides the same amount of cooling in kWh as the maximum power of your iStill. Without sufficient flow and cold enough coolant (< 8 degrees Celsius), the performance of your still will be affected negatively.
“From The Old Days (FTOD)” is a series of interesting iStill Blog posts from yesteryear. Is the info we shared still valuable? Is the craft distilling industry on track of improving, innovating, catching up with Big Alcohol? Or are these articles of old still just as valid today as they were back in the day when they were published?
This post continues where the last one stopped. Please read the first post on column design first. Better still, read the two posts prior to that, on boiler design as well.
I finished the first post on column design with a statement that needs further explanation: fruit brandy columns are not ideal for whiskey making. Let’s dive in deeper.
Fruit brandy column lay-out
Fruit brandy columns usually have a wide, broad column, completely made out of copper. Most of the time they do not sit directly on top of the boiler, but on top of an onion like structure called a helmet. Inside the column, there are usually 4, 5, or even 6 bubble cap plates. Near the top of the column you find the so-called dephlagmator. On top of that there may be an additional copper catalyst. After that some horizontal tubing that connects the column to the product cooler. Here’s where gasses get transferred from column to be cooled down to product.
The catalyst is a section near the top of the fruit brandy column filled with copper packing. It is there to deal with unwanted sulfur compounds. Fruit brandy ferments create lots of sulfer, that’s why a catalyst is needed.
The dephlagmator is a sort of column cooler. It is a section where the gasses that travel upwards go through tubes that are cooled with water. As a result part of the gasses condense and drop back onto the bubble cap plates.
Bubble cap plates
The bubble cap plates are filled with condensed gasses that fall down from the dephlagmator. The rising gasses, from the boiler or from the plate below, now have to travel through this liquid bath. In this way each plate, with liquids on top of them, effectively performs one distillation.
Wide copper column
The wide column ensures relative low vapor speeds. The column is made out of copper so it can help clean up sulfuric compounds.
What fruit brandy distillers look for
As we did with whiskey, we need to ask ourselves what a fruit brandy column needs to do in order to support the Master Distiller’s wish to make fine fruit brandy. Again, as with whiskey, the answer is easy: the fruit brandy column needs to help harvest the right tastes.
What the right taste components are for a fruit brandy? That’s easy to answer too. Contrary to a whiskey, that get’s most of its taste and character from (early) Tails smearing into Hearts, a fruit brandy gets its taste mostly from Heads smearing into Hearts.
With the Tree Metaphor in mind we can easily envision this: fruity tastes come over in the first parts of the run. During Heads. So … for a great fruit brandy the column needs to facilitate the smearing of Heads into Hearts.
Not much good can be found in Tails, when you are making a fruit brandy, so a well designed fruit brandy column makes sure Tails don’t come over.
The last thing a fruit brandy column is designed to do, is to clean up sulfurs. Sulfuric compounds are formed in abundance during fruit fermentation. They make the drink undrinkable. Fortunately, copper reacts with sulfur and sorta neutralizes it.
How this design favors fruit brandy making
The onion or helmet on top of the boiler (and situated below the actual column) does three things. Remember that high rpm spinner fruit brandy stills use? And how they throw the pulp high into the gas bed? The helmet creates extra head space, so the pulp (or grains, when a fruit brandy still is used for whiskey making) flying around does not enter the actual column.
The second thing the helmet does is create a buffer for turbulence. The turbulence is caused by the narrow boiler design and fast spinning agitator. The helmet sits well above that so that most of the turbulence created in the boiler gets a chance to subside, prior to entering the column.
Thirdly, the helmet functions as an expansion chamber, slowing vapor speed down.
The column, sitting on top of the helmet, is fed with low vapor speed gasses. The wide fruit brandy column design makes sure vapor speeds stay low during the entire distillation run.
Why slow vapor speeds help the fruit brandy distiller? Remember that big, heavy molecules need a lot of speed, when we want them to come over in the final product? Well, Ethanol needs much less energy to be distilled. And the Headsy fractions, like Methanol and Ethyl Acetate, need even less energy.
This is the really important part. Pay attention, please, here we go …
It is the lower vapor speeds that favor the separation of Headsy tastes and allow a fruit distiller to smear them in a controlled way into Hearts!
They need the low vapor speeds to ensure that at the beginning of a run more (and more pure) Heads come over. Due to the fact that they use relatively inefficient dephlagmators that can usually only cool down part of the gasses, higher vapor speeds would smear in too much Ethanol, making good cuts for Fores and Heads more difficult. The lack of total column control means they are left with no other option than to slow vapor speeds down as much as possible.
But … low vapor speeds mean no Tails come over, right? Right! But that is of no concern to the fruit brandy distiller. In a fruit brandy distillate the Tails only cause off-tastes and problems. It is a major concern when you want to make whiskey or rum, though …
In fact, apart from the low vapor speeds, even the water baths on top of the bubble cap plates, and their respective temperatures (ABV-related, off course), prevent the smearing of Tails into Hearts. Tails get trapped and accumulate in on the lower plates.
Low vapor speeds and copper are the key to fruit brandy distillation. The low vapor speed allows the distiller to work with Heads, while not having to worry about Tails. The copper takes care of the sulfur rich fruit brandy washes.
Instead of a narrow column, a wide column is better. Lower vapor speeds again. And efficiency isn’t very important. In fact, an efficient still, with insulated column will decrease the amount of passive reflux that helps fill the bubble cap trays. And the net energy gain, caused by augmented energy efficiency, will increase instead of reduce vapor speeds.
Oh, and last but not least, fruit brandy stills have a lot of plates. The alcohol needs to come off at a rather high ABV, in order to give the fruit brandy Master Distiller the capability to (1) Harvest a good Heads faction, while (2) still being able to get rid of unwanted Fores. Remember that the Heads and Fores factions are much more volatile and also much smaller than the Tails faction.
This is quite critical. Fruit brandy does not age as long as whiskey does. Neither do (unwanted, overly concentrated) Fores and Heads faction age out as well as early Tails do. The fruit brandy maker therefore needs more control. Because the 1860 technology does not provide total column management systems, he needs to have the extra plates and higher ABV to improve control.
And why it isn’t the best when making whiskey
We concluded in the previous post that a still designed for whiskey making should be efficient and have a rather narrow column. The narrow column creates the vapor speeds needed to carry over early Tails. The efficiency of the still makes it possible to use power management as an effective means to influence vapor speeds even more. More power in for more smearing, less power in for less smearing.
Fruit brandy stills don’t promote higher vapor speeds, so if smearing early Tails into Hearts is your goal, as it is when making whiskey … you will have a hard task at hand.
Most distillers that use fruit brandy equipment for whiskey making have to re-run their Tails again and again (I know one distillery that re-uses Tails five times!), just to get sufficient amounts of Tails associated congeners over in their final product.
Fruit brandy columns are made from copper and uninsulated. Copper radiates off incredible amounts of energy into the distilling room. That’s the second problem.
Even if you wanted to enforce higher vapor speeds by adding more power, most of that power just translates to more energy losses rather than higher vapor speeds. And even if you can circumvent that by for instance insulating the column … the additional gasses would just start throwing the water beds on top of the plates in the air, thus creating vapor channeling, where huge amounts of Tails can suddenly overwhelm both the system and your drink.
Third problem? Copper is expensive in two ways: to buy and to run. Yes it serves a goal when making fruit brandy, by keeping sulfurs under control, but grain washes only produce limited amounts of sulfur.
Copper is much more expensive to buy. And it is much more expensive to run, due to energy losses. An expensive and inefficient fruit brandy still means your whiskey’s cost price will be higher. Well, explain that to your shareholders, now that Craft Distillers too are faced with more and more intense price competition!
There’s yet another challenge, when you want to use a fruit brandy still to make whiskey. Fruit brandy stills have too many plates. Whiskey needs just two or three distillations, not four or five. There are three problems associated with redistilling whiskey too much:
- Capital investment and cost price: you buy more plates than you need;
- The taste will become thinner with each distillation cycle;
- High ABV new make whiskey spirit … needs to be watered down right away!
Whiskey needs barrel aging. And barrel aging takes place at around 60%. So, as long as the whiskey is distilled in such a way that proper cuts can be made, usually twice, let’s try to keep our Hearts cut as close to the 60% as possible. Why? Easy. If we have to water an 80% new make down to 60% … we dilute away around a quart of the total taste potential. When making whiskey, you are after taste. You want to harvest taste, not dilute it!
And that’s the third reason why whiskey made in a fruit brandy still is so often thin in taste. A recap:
- No Maillard Reaction in the boiler;
- Low vapor speeds and liquid baths on plates effectively block early Tails smearing into Hearts;
- High ABV new make spirit needs to be diluted right away.
Great whiskey can be “found” where early Tails smear into Hearts. Whiskey distillation therefore benefits from an efficient still combined with a narrow column for high vapor speeds. The high vapor speed helps getting over early Tails. An efficient still allows you to control that process by means of power management.
The very popular fruit brandy stills are not ideal, when you are in the pursuit of making great whiskey, because they are designed to harvest Headsy rather than Tails related congeners. Because of low vapor speeds, too many distillation cycles, and indirectly fired boilers, the whiskey tends to come over tasting thin.
Yes, for sure. Next post will be about how we apply the “lessons learned” and “vision shared” into our product designs. And maybe a fourth post after that? Yes, on brandy, rum and vodka.
“From The Old Days (FTOD)” is a series of interesting iStill Blog posts from yesteryear. Is the info we shared still valuable? Is the craft distilling industry on track of improving, innovating, and catching up with Big Alcohol? Or are these articles of old still just as valid today as they were back in the day when they were published?
The outcome of the Poll was an overwhelming “Yes”. So here we go: another more technical post. This time on column design. I foresee three articles. This first one will lay the groundwork on how a column should perform. The second one will analyse the workings of the bubble cap column, since that’s the one most often used by Craft Distillers. The third post will zoom in on how we translated our design philosophy into creating the iStill 250 and iStill One family.
In this post, on how to design a good column, we focus on whiskey making. More posts will follow, that will deal with other drinks.
Why start with whiskey? Well, because … there’s quite the gap between many of the designs used right now for whiskey making and how a whiskey column should be designed optimally. A nice starting point, therefore!
It is advised to read both posts on Boiler Design prior to starting to read this one. A good design starts with the boiler. And the groundwork of how I feel about total still design is laid out in those two posts. Well designed columns, literaly as well as in a figurative way of speaking … have a great boiler at their base.
What are we after?
It is easy to say that this or that design is better. But how to measure? What is the goal? Luckily, in whiskey making, that’s quite easy. As it is the case with all taste rich drinks … when distilling a whiskey, we are after taste. So a column should be designed in a way that allows for maximum taste transfer. Now, that’s a starting point, we can depart from.
Next question is … where can the taste of a whiskey be found? That’s a question that’s less easy to answer, but let’s dive in deeper and find out.
The tree metaphor
I find the “Tree Metaphor”, that I originally developed for gin recipes, helpful. You can envision a distillation run by looking at a tree, “outside – in”. That’s the trick.
The first thing you see and the first things that come over are the fruits AKA fruity notes. When you dive in deeper, you notice the leafs, AKA herbs (the metaphor was originally designed for gin, remember). The stem or trunk comes next, representing the body or Hearts. And you have to dig them up, and really go in … but there’s roots too. Rooty and nutty flavors are found in Tails, the last bit of the run.
Simplified, and translated to whiskey making, there’s fruity tastes in the Heads, body in the Hearts, and rooty and nutty tastes in Tails.
Now the next step … taste definition of whiskey … whiskey certainly has body, and some whiskies have some fruitiness, but the main character trait of whiskey is its rooty and nutty notes. That’s Tails associated.
In other words … it’s the (early) Tails that are most important, when you are in the pursuit of making a great whiskey.
That’s where – after some aging – the goodies, the character, the multi-dimensional after taste, that lingers and lingers in your mouth, can be found.
If early Tails have the most impact, when in the pursuit of a great whiskey, the column of any whiskey distillery should facilitate harvesting those early Tails, right? But what are the properties and qualities of early Tails? It is only when we know these, that we can start to put together a framework of “do’s” and “don’ts”, when we want to design a great column for whiskey distillation.
Early Tails and the art of smearing
We want some Tails into the last parts of the Hearts run. That’s the goal, when making a great whiskey. This process is also called “smearing”, where – instead of pure and perfect cuts – there are Tails and Tails related congeners (taste molecules) “smearing” into the last part of the Hearts cut. The more Tails congeners you harvest during the run, the more taste potential your whiskey will gain. But reaching that full potential will evidently take longer aging.
When do Tails come over? Yes, at the end of the run, that’s for sure. But how late? The later they come over … the more compacted they will be. Very well compacted Tails come over very late, so your Hearts cut will be quite big, but there won’t be any Tailsy congeners … until they come over. And then it is too late. Due to the compaction, they come over all at once. Like a big gulp, over-contaminating Hearts and making the final product undrinkable.
When making whiskey, great Tails compaction and control either don’t bring over taste or overpower it completely. Perfect Tails compaction just became enemy of state … Now, that’s a statement that can help out, when designing the perfect whiskey column!
Properties of Tails
When Tails management is essential to creating world class whiskey, the properties of Tails need to be further investigated. That sounds like a challenge, right? Chemistry and stuff …
Fortunately, it all boils (literally!) down to … boiling points and weights. Wait, let’s turn that around: molecular weight and boiling points.
Simplified, Tails associated alcohols like Propanol, Buthanol, and Furfural are “heavier” (= have more inter-molucular bonding power) than the good alcohol called Ethanol. Because they are “heavier”, they don’t escape a boiling concoction (AKA your distiller beer) as easy as lighter alcohols or Ethanol. And when they do, most of them are so heavy that they fall back. Back into what? Back into the distillers beer you are currently distilling.
Since Tailsy alcohols are heavier, they do not come over until the last part of the run. And they only come over when enough energy is applied for them to make it to the column and beyond. Energy? Yes, energy. Energy that is translated to speed. Remember, Tailsy alcohols are big dudes with an overweight problem. You need to put a lot of energy in them to get them moving. And it takes a lot of speed to get such heavy molecules all the way over to the product condensor.
Speed? Did anyone just say “vapor speed”? I guess I just did …
Vapor speed is king
When it comes to Tails management, vapor speed is king. Low vapor speeds are great for Tails compaction, but there may simply not be enough speed to carry early Tails over into Hearts. High vapor speeds are what you need if you want to smear early Tails into Hearts.
How to increase vapor speed
We established that a great whiskey can only be made when we master the art of smearing early Tails into Hearts. Translated to column design, this means we need a column (or distillation system) that allows us to do that in a gentle, controlled manner.
There are two ways in which we can increase vapor speed:
- Increase power input;
- Decrease column diameter.
Increasing power input creates more gasses that travel through the column at a faster speed. A smaller diameter column does not create more gasses, but dramatically increases vapor speed.
A – relative – increase in power input can be created by designing efficient stills. The less energy is used to heat-up the distilling room, the more energy is left to play around with vapor speeds. The smearing of early Tails into Hearts can be facilitated by designing relatively small diameter columns. Small diameter columns in combination with efficient stills.
Hey, did you notice that? All of a sudden we have “do’s” and “don’ts”! Let’s approach it from the positive side … so what are the “do’s”? What do we need to do in order to create the best column for great whiskey making? The total rig needs to be efficient. And the column on which final cuts are made needs to be relatively narrow. Time for an example from practice.
How the Scots do it
The Scots, like no one else, make whiskies that have lots and lots of taste. So they must master the art of smearing early Tails into Hearts, right? How do they do it? Magic? Heritage? No, they do it by designing an effective still … with a narrow column. The stills the Scots use to help them smear early Tails into Hearts are quite efficient and have high vapor speed columns.
How they make the rig on which they want to smear early Tails into Hearts efficient? Easy, by doing a strip run first. The strip run augments total ABV from something like an 8% wash to a 25 to 30% low wines. And that’s what they charge their spirit stills with. Filling them with higher ABV charges dramatically increases the efficiency of their spirit run.
How they create high vapor speeds, that allow Tails to smear into Hearts, on the spirit run? By applying long, narrow, swan-neck designed columns. Narrow colums that increase vapor speed, so the smearing they look for can actually be accomplished. Remember higher vapor speeds are needed to transfer Tailsy molecules from the boiler to the final product.
Scotland versus the rest of the world
Scotland versus the rest of the world? Let me re-write that into: “Scotland vs. Germany”. Remember my posts about boiler design? And about how Craft Distillers from around the world not only wanted to buy BMW and Mercedes cars, but also shiny German distilleries? And if they can’t afford them … one of their Chinese clones? Well, that’s the match we are actually watching here.
Scotland – Germany? No, let me rephrase that again. Whiskey still versus fruit brandy still. Doesn’t that make sense to you? In that case, please read my two posts on boiler design first. If you do, for sure the above remark will make sense.
German still manufacturers conquered the world by selling Craft Distillers on all continents fruit brandy stills. Do you remember that this causes many of today’s Craft Distillers to run stills with boilers that are designed sub-optimal? Well, let me enlighten you on something else. Fruit brandy columns aren’t that well suited for whiskey making either. Neither are they suited for rum and vodka making, and only partially do they support making brandy from wine. But that deserves a new post. That will be in “Odin on Whiskey Column Design (2)”. You want me to lift the veil a bit? Okay, here we go. Remember those fruit brandy stills have boilers that are too narrow and high for efficient distilling? Well, fruit brandy columns are actually too wide …
iStill 5000 Hybrid with glass column segments …
The direct operating costs of producing a liter of new make whiskey or rum on an iStill, ready to barrel at 65%, are EUR 0,49 versus EUR 1,99 on a traditional copper potstill. Producing whiskey or rum on an iStill reduces operating costs with as much as 75%, when compared to a traditional copper potstill. The lower operating costs of running an iStill translate into higher margins and a more sustainable, future-proof business model.
This iStill Blog post presents an operating cost comparison for new make whiskey or rum production. iStills versus traditional set-ups. Why operating costs are important? Well, the lower they are, the higher your profit margin – given a certain selling price. Higher margins allow you to make more money or use part of that extra margin to weather through tough times. Also, lower operating costs signal a more eco-friendly, more environmental and sustainable business model. Less energy consumption equals a lower carbon footprint.
Of course we know the iStill numbers through-and through. The numbers of traditional stills, that we present in this iStill Blog, are based on feedback we got from customers experienced in running traditional equipment before switching to iStills. If the manufacturers of more traditional, copper stills feel that the examples underneath do not do their distilling solutions total justice, please reach out to us directly, so we can discuss and – where needed – amend.
Operating costs are the expenses associated with the maintenance and administration of a business on a day-to-day basis. Rent of the building, power to run the stills, the costs of buying in grains or other substrates, staffing costs, equipment depreciation costs, etc.
In order to keep this post relatively simple and to the point, we’ll focus on the variable costs of running the still, depreciation costs of your distilling machine, and the staffing needed to keep on distilling. Costs like the rent of the building or substrate purchase costs won’t be investigated, since they are (in the context of this iStill Blog post) considered a given. Meaning they don’t necessarily vary a lot between different still options.
Calculating energy costs for whiskey or rum
The efficiency number of a traditional potstill is around 35%. A traditional potstill needs two distillation cycles to bring an 8% whiskey beer or rum wine to the barrel aging strength of 60 – 65%. The iStill can turn an 8% base beer or wine into 60 – 65% new make in one go. So you save the manpower and energy of at least one run.
The iStill 2000 uses around 280 kWh to make rum or whiskey new make spirit. The associated costs are per run are well under EUR 50,-. Given the inefficiencies of the traditional set-up, a total energy usage of 800 to 1000 kWh is expected per run. This translates into direct energy usage costs, for a double distillation, of around EUR 190,-.
The amount of 2000 liters of base beer translates into about 220 liters of 65% strong new make spirit. When we divide the energy usage per still type by the number of liters of new make produced, we can learn the energy costs per liter. For the iStill the energy costs per liter are EUR 0,22. For the traditional copper potstill the energy costs per liter are EUR 0,87.
Calculating depreciation costs for whiskey or rum stills
A traditional 2000 liter copper still, made by a reputable manufacturer costs at least EUR 200.000,-. The iStill 2000, with some options, is around EUR 80.000,-. Because the iStills are made from chemically resistant stainless steel, instead of copper, the unit has an expected longevity of around 20 years.
The copper or stainless steel boiler of a traditional set-up may have the same longevity or slightly less. The copper column or riser oxidizes and suffers from the continuous need for (acid) cleaning. It is usually eaten away in around 10 to 15 years. Adding up boiler and column life expectancy for traditional potstills and averaging them out, leads to an overall total system longevity of 15 years for a traditional copper potstill.
Following a lineair depreciation curve, the 80k iStill 2000 has an annual depreciation of EUR 4.000,-. Based on 200 runs per year, the depreciation costs per run are EUR 20,-. When one run produces 220 liters, the depreciation costs per liter are EUR 0,09.
Following the same lineair depreciation curve, the EUR 200.000,- traditional copper potstill has an annual depreciation of EUR 13.300,-. At 200 runs per year, this translates into EUR 66,50 of depreciation per run or EUR 0,30 per liter of new make spirit produced.
Calculating staffing costs for whiskey or rum
Manning the still costs time, and time is money. Managing a traditional still asks for constant supervision. Cleaning can take 2 to 3 hours. Often the boiler design and column/riser design are not optimized for 8 hour shifts. How much manpower does it take to run a traditional still? At least 1 FTE. How much manpower does it take to run the iStill, which is automated and needs much less cleaning down-time? Around 0.2 FTE.
Say that hiring a distiller costs EUR 36.000,- per year. Running a traditional set-up then adds EUR 36.000,- to your overall costs. The iStill – by comparison – costs less than EUR 8.000,- to staff. A stunning difference of EUR 28.000,- per year.
In the above example, where we use a 2000 liter still to make 220 liters of 60-65% new make spirit per run, doing 200 runs per year translates into 44.000 liters of new make. The staffing costs of a traditional system are EUR 36.000,-, which translates into additional variable costs per liter of EUR 0,82. The much lower effort needed to run the iStill 2000 translates into only EUR 0,18 of staffing costs per liter.
iStill: reduce your operating costs by 75% …