#2 Milling
Milling
Our Unique Approach to Milling
We use a disc mill that operates similarly to a large coffee grinder. This process preserves the integrity of our organic malt and ensures a tight particle size distribution, which is essential for our proprietary mashing and fermentation processes. We gently crack open the malted barley kernels, keeping the husks, inner starch, and all other components together. This method maintains the barley's natural balance and complexity, which are crucial for our production.
Mashing and Fermentation
The Mashing Process
Combining Malt and Water
Our mashing process begins with combining our gently opened malt with precisely temperature-controlled water in our mash tun. This mixture initiates the extraction and conversion of the grain's starches into fermentable sugars.
Temperature Control
We perform a carefully temperature-controlled mashing process to convert starch to fermentable sugars and preserve the natural lactic acid bacteria on the grain.
Our Unique Approach
Unlike traditional methods, we don't separate the liquid wort from the grain solids at the end of the mashing process (known as lautering). Instead, we keep everything together – the converted sugars, proteins, fats, and all the flavor compounds from the entire grain. This approach ensures that we capture every nuance of flavor and every bit of fermentable sugar from our organic barley.
The Fermentation Process
Yeast Selection and Inoculation
Our fermentation process uniquely integrates distiller yeast and natural lactic acid bacteria from the grain. We emphasize utilizing the indigenous lactic bacteria on the barley alongside carefully selected cultured yeast strains, enhancing the complexity and depth of our Danish flavors.
Primary Fermentation
The primary fermentation phase is rapid, where yeast converts simple sugars into ethanol and carbon dioxide. This stage typically lasts 2-4 days and is maintained at controlled temperatures.
Secondary Fermentation
Following the primary phase, a slower and more nuanced secondary fermentation occurs. During this period, the yeast and the lactic acid bacteria produce complex flavors, contributing to the New Make and the whisky's intricate flavor profile. This phase can extend from a few days to over a week, depending on the desired flavor characteristics we aim to achieve.
Temperature Control and Monitoring
Throughout both stages of fermentation, we rigorously maintain temperature control. This critical process prevents unwanted bacterial growth and ensures the yeast and lactic acid bacteria remain active and efficient. Our proactive approach allows us to make necessary adjustments and avoid the development of off-flavors.
Distillation
The Müller Hybrid Still
Distillation is at the heart of our whisky making process. We use a custom-built contemporary Müller hybrid still that integrates the functionalities of pot and column stills. This 1000-liter capacity still consists of five main components:
Pot Still
The pot still is the primary vessel for heating the wash, enhancing flavor by retaining more congeners, essential compounds contributing to the complexity of the whisky.
Plate Column with Two Plates
The plate column has two plates and functions as a crude separation unit, removing water from the alcohol vapors.
Aromat Column
The Aromat column is a compartment with a helix-shaped copper plate designed to enhance reflux, expand the condensation surface area, and refine compound separation. The alcohol vapor rises to the top towards the cold dephlegmator. The higher seething portion of the vapor flow condenses, and the liquid flows downwards throughout the helix-shaped plate. A continuous substance exchange between the upward-rising hot alcohol vapor and the downward-flowing liquid takes place. The process evaporates lighter-boiling flavorful alcohols, esters, and other flavor components while discharging heavy-boiling components such as fusel oils and water.
This design ensures that only the most volatile and desirable compounds ascend to the top to reach the dephlegmator, thereby improving the spirit's purification process.
Dephlegmator
The dephlegmator acts as a partial condenser at the top of the Aromat column. It boosts reflux by condensing some of the ascending vapor back into liquid form, further enhancing the separation process. By controlling the temperature of the Dephlegmator, we control which flavor components can pass through to the Condenser.
Condenser
The condenser is a critical component in the distillation process. It transforms the alcohol and flavor vapor passed through the Aromat column and Dephlegmator into a liquid form. This transition from vapor to liquid is essential for collecting the distilled spirit in its final form.
Our Single Distillation Process
Unlike many whisky producers who use double or triple distillation, Copenhagen Distillery has perfected the art of single distillation. This method requires meticulous precision yet allows us to preserve various flavors while achieving the desired purity.
Heating the Wash
We initiate the process by heating our wash, typically containing 11% ABV. Starting at approximately 92°C and gradually rising to above 100°C, the temperature causes alcohol and other volatile compounds to boil and vaporize from the wash.
Copper Interaction
During the distillation process, the vapors interact with copper surfaces, a critical step for eliminating sulfur compounds that may introduce unwanted flavors. Copper binds with sulfur, resulting in copper sulfide remaining within the still. Copper is also a catalyst promoting the formation of esters; alcohol reacts with small organic acids.
Separation of Fractions
As the distillate emerges, we meticulously separate it into three fractions:
Heads: We discard the initial 1% of the distillate - also called low wines, which contain very volatile compounds that are often harsh or unpleasant.
Heart: We collect the heart, a prime cut rich in ethanol and desirable flavor compounds, free of off-notes, when the distillate is between 92% and 70% ABV. On average, the collected heart is 88% ABV.
Tails: We remove the remaining portion, called the Tails, which contains heavier compounds that will lower the whisky's quality.
Impact on Flavor and Quality
Our single distillation process in the Müller hybrid still results in a spirit that is both pure and characterful. Our still's advanced design, combined with our rigorous process, ensures remarkable consistency from batch to batch. We retain a wide range of congeners, ensuring a high complexity New Make results in a higher complexity after cask maturation.
Energy Efficiency and Sustainability
We've implemented several energy-saving measures in our manufacturing process. Cooling water from the distillation process is collected and reused for the next mashing process run. Additionally, we use the heat generated during mashing, fermentation, and distillation to create a microclimate that accelerates the cask maturation process independent of the outside temperature and climate. All electrical power used in the whisky manufacturing comes from solar or wind energy.
Maturation in Hungarian Oak Cask
Our Choice for Excellence
At Copenhagen Distillery, Hungarian oak plays a vital role in the maturation process of our Organic Single Malt Whisky. The unique properties of this oak, combined with our careful toasting process, contribute significantly to the distinct flavor profile and the quality of our whisky.
Tight Grain Structure
The Hungarian oak (Quercus frainetto) we use is around 150 years old before being harvested. It is air-dried for 18 months before the cooper begins crafting proprietary casks, toasted according to the Master Distiller's specifications. This toasting process is vital to creating the distinct flavor of our single malt whisky.
Sustainable Sourcing
We source our oak from sustainably managed forests, ensuring environmentally responsible production and supporting forest conservation and regeneration efforts.
The Art of Toasting
Toasting the interior of our virgin Hungarian oak casks is a critical step in developing the flavors the wood will impart to the whisky during maturation. We employ various toasting levels to create diverse flavor profiles:
Light Toast
Flavor Profile: Develops subtle flavors such as warm spices with many tannins and mild vanilla, allowing the wood's natural characteristics to shine.
Medium Toast
Flavor Profile: Enhances vanilla, caramel, and light, toasty notes while preserving warm spices and heavy tannins, providing a balanced flavor profile.
Heavy Toast
Flavor Profile: This toasting level introduces deeper flavors like coffee, chocolate, heavy and dark sugars, and ripe stone fruits and reduces the amount of tannins in the whisky.
Cask Size and Maturation Dynamics
Optimal Surface Area to Volume Ratio
Our 225-liter casks create an optimal balance between surface area and volume, allowing significant interaction between the whisky and the wood. This interaction promotes the extraction of desirable compounds without overwhelming the spirit.
Temperature-Controlled Maturation
We leverage both natural and controlled temperature conditions to enhance our whisky's maturation process:
We take advantage of the residual heat generated during the distillery's mashing, fermentation, and distillation. This fluctuation of warmth encourages interaction between the whisky and the cask.
Our warehouse employs a custom heating system that replicates the conditions in the distillery, maintaining fluctuating temperature conditions year-round.
Our approach to temperature-controlled maturation demonstrates how we blend traditional whisky-making techniques with innovative methods to create our distinctive Danish whisky, which doesn't require prolonged maturation.
Oxidation and Esterification
During maturation, two key chemical processes occur:
Oxidation: Oxygen interacts with the whisky through the wood, leading to the development of complex flavors. This process softens harsher notes and enhances the overall profile of the spirit.
Esterification: Fluctuating temperatures accelerate the chemical reaction between alcohols and acids, producing esters that contribute fruity and floral notes, enriching the whisky's complexity and depth.
Bespoke Casks and Customization
At Copenhagen Distillery, we elevate customization by crafting bespoke casks with unique flavor profiles tailored to specific whisky expressions. Examples include:
Blood and Bone: Casks specifically toasted and seasoned to enhance deep, rich flavors with robust, earthy notes.
Aquavit: Casks designed to impart complex herbal and spice characteristics inspired by the traditional Scandinavian spirit.
Bottling
At Copenhagen Distillery, we select several different casks to craft our whiskies. We blend their contents to ensure a harmonious balance of flavors. Even when the casks are made from the same type of wood, are the same size, and are stored under identical conditions, flavor variations still occur.
We produce whisky in small batches, drawing a specific amount from each barrel. At the same time, large commercial distilleries aim for consistency year after year, where we strive for unique flavor experiences. Each batch is different. We select casks based on the desired expression and blend the contents for the perfect balance. Sometimes, we use only part of a cask's contents.
Determining the Ideal Alcohol Strength
Determining the ideal alcohol strength for our whisky is an art. While there are minimum legal requirements for specific categories, we choose the final alcohol percentage based on where the whisky's character shines best. We blind-taste all whisky versions at different strengths to find the optimal balance between color, scent, mouthfeel, taste, and aftertaste. For instance, we bottled RAW Batch 2 at 51.6% alcohol—not 51.7% or 51.5%, but precisely 51.6%—as it was the perfect strength for achieving the perfect whisky expression.
Bottling Process
After determining the alcohol strength with the perfect balance, we carefully bottle the whisky, seal it with wax, and label it—all by hand—and then it's ready to be enjoyed.