We drew a few bottles of rum from our barrels. Just to see how they are doing. They aged for 2 years and 2 months. Tasty? Very tasty! Already at their prime? No, not yet. We intended to distill this rum in such a way that 4 years of aging would make it perfect. It is pretty darn impressive already. And almost there. All we need to add to it … is a little more patience.
Made us some whisky liqueur, last week. Not that difficult. Take a half decent whisky – or if it iStill made: take that amazing whisky – and add honey to it. Heather honey, preferably. Try 250 to 300 grams per liter.
If you make your own whisky, start with higher proof, because the goal would be to reach a liqueur with an alcoholic strength of 40 to 45%. I personally like it at the higher end, but it takes premium ingredients to get you there. When you start out with a very feisty whisky, the alcohol burn might overshadow the sweetness of the honey.
Additions? Well, some orange or even pear extract – made on the iStill Extractor of course – could make a nice addition. But let your creativity run and come up with some personal touches yourselves, please!
It is basically a mix, age, settle-and-rack-off kinda operation. You mix the honey into the whisky. You let it rest for about two months. You then rack-off the clear liquid that sits above a small layer off sediment that comes from the honey. Bottle and enjoy! I like mine served cold, even on the rocks …
The iStill University organizes a new Certified Master Distiller Training in September. When exactly? From Monday September 5th until Thursday September 8th. Where? In the Netherlands at iStill HQ!
The Certified Master Distiller Training continues where the Certified Craft Distiller Training stops. The first course is mostly theoretical and provides the groundwork of knowledge each and every craft distiller should have. The master distiller course in September is all about training. Training your taste buds. Training you on how to make whiskey, rum, brandy, gin, vodka, and liqueurs. You’ll basically be spending four days behind various stills, making various products, guided by our master distillers. Master distillers that have developed over 450 award winning recipes … and they are at your service!
We still have three places available, due to one customer having to delay their training. Want to learn more about distilling? Want to learn more about the Certified Master Distiller Course? Please reach out to Veronika@iStillmail.com
The iStill is not just a still, it is a complete distillery in itself. The iStills can mash, ferment, and distill. No more need for mashers, fermenters, and/or stripping runs? How’s that for flexibility and ease of use? Quite the game-changer, yes, we know, but that’s not the topic of today’s iStill Blog post. What is? Well, let’s dive deeper into grain to water proportions. How much grain can one dump into the iStill? We’ll use the iStill 2000 as a reference. If you want to translate that to your i500, just divide by four. Do you run an iStill 5000 instead? Multiply the examples underneath by 2.5.
What is your goal?
Mashing is the first step in making spirits. It’s where you break-up starches into fermentable sugars, so that – in the second step of making spirits – yeast can convert those sugars into alcohol.
The more grain you mash-in, the higher the sugar content of the fermentation will be, and the more yield you’ll get. The less grain you mash-in, the lower the sugar content will be. High sugar content washes are best for lighter spirit profiles. Lower sugar content washes result in lower yield but provide higher relative flavor content in the end-product. Lower sugar washes are best for heavier spirit profiles.
Rule of thumb
Here’s an easy to remember rule of thumb: use four liters of water for every kilo of grain. Or, going imperial, 2 pounds of grain per gallon of water. How this translates to the iStill 2000? Use 1600 liter of water and about 400 kilograms of grain. It will get you to about 8% after fermentation.
As a beginning distiller, or a distiller working with new (iStill) equipment, we always advise caution. A good start builds confidence. Overcharging or overfilling your still will create a mess, and takes away confidence.
On a first mash, we advise a grain dump of 375 kilos on 1600 liters of water. Use the agitator to the max, dump the grain slowly, and preferably use a hydrator to make sure the grain is wetted before it enters the kettle. Why the lower than 400 kilo grain dump? Because even with imperfect mixing, conversion, etc. you are still well within the threshold of the still’s filling and heating capacity.
What to expect from a 375 kilo grain dump on 1600 liters of water? An SG of 1.069. With a FG of 1.010, this results in a theoretical yield of 7.61%, when fermentation is done. Taking some losses due to CO2 vent-off released alcohol and yeast propagation at the earliest fermentation stage, expect a net yield of 7.1 to 7.2%. Did everything work out okay? Move up a bit and go towards maybe 400 kilo’s of grain on your next run.
As you grow experience and confidence, here’s a protocol that pushes it to the limits. 1600 liters of water and 440 kilos of grain. On this mash protocol, you need to use both the agitator to the max, and bring the iStill Mash Pump into play. How? Recirculate the mash via the drain and iStill Pump back into the boiler, while you mix and add more grain. This makes sure that – even at the higher grain dump levels – all grains are dissolved and wetted perfectly. Essential for maximized yield.
What to expect from a 440 kilo grain dump on 1600 liters of water? An SG of 1.081. With a FG of 1.010, the result is a theoretical yield of 9.158%. Considering that yeast propagation – in the early fermentation stages – and CO2 release result in some losses, expect a net yield of 8.5 to 8.6% for your whisky.
Here’s the complete calculation (thanks Richard!)
Okay, here we go. For that truly unique Scandinavian experience …
1. Ingredients (per liter):
- X liter of 60% well cut neutral (about half of your iStill’s boiler size)
- 15 grams of caraway seeds (crushed) per liter of 60% neutral
- 5 grams of coriander seeds (crushed) per liter of 60% neutral
- 1 gram of dill per liter of 60% neutral
- 0.5 gram of cardamom per liter of 60% neutra
2. Approach (boiler infused Akvavit):
- Add the herbs to the 60% neutral in the boiler
- Allow it to macerate for 12 to 24 hours
- Add water to lower the ABV from 60% to 30
- Pot distill (you will probably collect 40% of total boiler contents)
- Dilute to 42% drinking strength
- Give the drink 5 weeks rest in a glass demijohn before you try it
- You want twice as much? Just do everything “times two”. Ten times more? Multiply by 10. Good luck!
- Barrel aging? Sherry casks go really well with Akvavit together …
- 3 to 6 months at 60%, then dilute to 42%, then let it rest for another 5 weeks
And caraway seed is still the most important herb in Akvavit. Like anise in Raki or juniper in Gin. A tradition that goes back hundreds of years …
Nowadays, Akvavit is made out of a more complex herbs bill. Herbs like caraway, dille, cardamom, cumin, anise, and even grains of paradise are used.
The base of the drink is no longer a crudely distilled beer. A vodka made out of grains or potatoes is used as the base liquor.
It shouldn’t be a surprise that the name “Akvavit” has the same origin as Whiskey: it is derived from “Aqua Vitae”. That’s “water of life” in Latin.
Akvavit is usually 40% strong and white. It is served cold and it is served at special occasions. The Danish and Norwegians drink it around Christmas or Easter. In Sweden, Akvavit is more of a staple schnapps, consumed at … well, pretty much any occasion actually.
Norwegian Akvavit (called “Akkevit”) stands out from the pack. Norwegians drink their Akkevits at room temperature. Most Norwegian Akkevit is actually aged on wooden casks. The maturation process (or actuall: the “wooding” process) is very similar to how Dutch Genever is matured: for a relatively short time and preferably at sea. I guess these similarities in traditions can be traced back to the fact both the Norwegians and the Dutch have a strong sea faring tradition and culture.
I don’t know what ageing in wooden casks does to Norwegian Akkevit, since my experience is with “white” unaged Danish Akvavit mostly. My guess is, taste is both more mellow and more complex. But that is just guesswork. If anybody can give an update based on the experience of actually drinking Akkevit, please step in!
Akvavit is a great companion to herring and rye bread. Somehow the drink and the fish bring out the best tastes, when combined.
Nowadays, Akvavit is mostly consumed by elder people, in Scandinavia. In the past the drink was made and consumed in the Baltic states, Northern Germany and The Netherlands.
In the next article on Akvavit, I will share my recipe. Let us put it to good use and bring back Akvavit to the younger generations!
Here’s a new idea, that we’d like to run by you. An air pressure filter concept, that helps separate liquids from solids. If you have feedback to share, if you feel we should or shouldn’t bring this to the market place, please don’t hesitate to email me personally via Odin@iStillmail.com.
We see three potential use-cases:
- Post-mashing and pre-fermenting liquid from grain separation;
- Post-distilling grain and botanicals compaction and alcohol yield maximization;
- Post-extraction botanical compaction and alcohol yield maximization.
The first use-case can be helpful when making vodka. Vodka aims to be neutral. Off the grain fermentation and distillation minimize esterification. So, by using the air pressure filter concept, the grains and liquids could be separated for a cleaner ferment and distillation, which will ensure a more neutral flavor character.
The second use-case high-lights waste-compaction and yield maximization. Via the air pressure filter concept, the post-distillation grain (whiskey) or botanical (gin) waste can be compacted to the max. This minimizes costs associated with waste management. Also, by drying out the now spent grains or botanicals, a maximum amount of alcoholic liquids is recovered.
The third use-case mirrors the second one. The air pressure filter concept can be used post-extraction, so that wasted fruits, berries, and herbs can be compacted, while alcohol yield is maximized.
We are looking to achieve the following goals with the air pressure filter concept:
- Empty and separate grains from an iStill 2000 mash in under 20 minutes;
- Compact the wasted grains, berries, etc. to 40% of their original volume;
- Realize a dry instead of wet waste;
- That helps improve alcohol yield by as much as 10% vs. wet filtration.
The air pressure filter concept would work like this:
- Feed the system with the grain/water or botanicals/alcohol mixture;
- Pressure the system and separate liquids while compacting the solids;
- Repeat until the compression chamber is full;
- Empty the compression chamber;
Air pressure filter concept …
Wanna learn all about heads, hearts, and tails? Want to understand how your cuts define the spirit you make? Do you want to be trained in the art of fractionating heads, hearts, and tails? Reach out to Veronika@iStillmail.com and register for one of the iStill University Courses!
It is considered the most daunting thing, while learning how to become a distiller: how to cut your heads, hearts, and tails fractions correctly. Is it important to receive training? Yes, it is, because cuts are directly related to the flavor composition of your drinks.
Smear more heads into hearts and you will get more fruity flavors over. Good for a floral gin or apple brandy. Smear more tails into your hearts faction, and you’ll create a drink with a longer finish, that’s able to cope with prolonged barrel-aging. And there’s more, much more to it.
It would hardly be an over simplification to state that learning how to cut for heads, hearts, and tails, is the essence of becoming a good distiller. And we, at the iStill University, have developed the theory and education to help you – in an objective manner – learn how to make perfect cuts on all of your recipes.
Creates chemistry …
Yesterday morning, we started fermenting a 500 liter on the grain whisky batch in the iStill 500. Starting SG was 1.047. Today, just 24 hours later, the fermentation has finished at SG 0.998. A 6% yield in 24 hours.
How is this possible? How can iStill Advanced Fermentation Protocols create a 4 x faster fermentation, basically limiting fermentation time as the craft distiller’s bottle neck?
It has everything to do with controlling the fermentation. Firstly, we fermented with pH Control (pH 6.5 – 4.8). Secondly, we fermented at a constant temperature of 27.5 degrees Centigrade. Thirdly, we have developed an advanced yeast nutrient recipe, that we added to the mix. Fourth? The iStill 500 is now equipped with a fermentation specific agitator protocol …
Want to learn how to increase your fermentation yield and quality, while slashing throughput times? Reach out to Veronika@iStillmail.com and register for the iStill University! Want to understand what our distilleries can do for you? Then plan a call with Esther@iStillmail.com.
Happy yeast makes better alcohol faster …