When it comes to making grape based brandy, Cognac shines as a beacon of excellence. Their meticulous methods and deep understanding of the craft have set a standard admired and aspired by distillers worldwide. For those keen to improve their brandy distillates, it’s a good place to start the search for how…
This article serves as a comprehensive guide for those seeking to elevate their grape distillates, drawing inspiration from the time-honoured techniques and subtle artistry of Cognac producers.
By delving into these processes, we aim to provide distillers with insights and practical strategies to enhance the quality of their brandy, aiming for a level of sophistication and finesse akin to that of Cognac.
Ethanol vs Ethanal
Improving brandy distillates starts with some basic understanding – the difference between ethanal and ethanol. It’s not a typo, it’s not semantics. It’s worth taking a moment to refresh your knowledge about it.
Ethanal (acetaldehyde) and ethanol are both compounds found in brandy, but they have distinct chemical properties and impacts on the final spirit.
Ethanol: The primary alcohol in brandy
Ethanol is the type of alcohol most commonly associated with alcoholic beverages. It’s a simple alcohol with the chemical formula C2H5OH.
Ethanol is the primary alcohol in brandy, formed during the fermentation process when yeast converts sugars in the grape must into alcohol. It’s the main component that gives brandy its alcoholic content. It also carries many of the flavours and aromas that are further developed during ageing.
Ethanal: A compound with a double-edged impact
Ethanal, or acetaldehyde, is an organic compound with the formula CH3CHO. It’s a type of aldehyde and is more reactive than ethanol.
Ethanal is produced during fermentation but in smaller quantities than ethanol. It can also form during the oxidation of ethanol. In small amounts, ethanal contributes to the complexity of brandy’s flavour profile, adding subtle fruity and fresh notes. However, in higher concentrations, it can impart a sharp, unpleasant smell often described as pungent, green, or like cut grass.
During distillation, especially in the heads cut, distillers aim to remove excess ethanal to prevent it from dominating the flavour profile. The skill in distillation lies in balancing the removal of undesirable levels of ethanal while retaining some of its beneficial characteristics.
Managing ethanal
If you want to improve your brandy distillate, distillers should become adept at identifying the presence of ethanal through smell and taste. It often presents as a sharp, green apple-like aroma in the distillate.
Then look towards two areas to reduce it – the fermentation and distillation phases.
Proper fermentation management can help control ethanal levels. Conditions that lead to excessive oxidation or that stress the yeast can increase ethanal production. Meanwhile, making accurate heads cuts in the distillation process is crucial. This is where ethanal is most concentrated, and its removal is essential.
Improving brandy distillates by understanding malolactic fermentation
Malolactic fermentation is a critical step in the production of many wines and spirits, including brandy. It’s a process that can significantly alter the profile of the distillate, primarily through changes in acidity.
What is Malolactic fermentation?
Malolactic fermentation is a secondary fermentation process where malic acid in the wine is converted to lactic acid by bacteria. This conversion leads to a decrease in the wine’s acidity, as lactic acid is less sharp and less pronounced than malic acid. The process also slightly raises the pH level of the wine.
Impact on brandy production
In the context of brandy production, the timing of malolactic fermentation influences the final spirit’s character. By avoiding malolactic fermentation, distillers can maintain acidity, which is crucial for generating bright, vibrant eaux de vies. Conversely, by distilling a ferment with less acidity (resulting from allowing malolactic fermentation) can lead to softer, rounder eaux de vies.
As climates change and pH levels in wines gradually rise, some of the famous producers may opt to skip malolactic fermentation to retain their acidity and combat the effects of a warmer climate. Others might embrace it to soften their brandy and add complexity. Keep up to date with industry thinking on this as it will play out globally – not just in Southwestern France…
Malolactic fermentation is a process that can fundamentally shape the character of the final spirit. By carefully considering the timing of this process, and whether to do it or not, distillers can manipulate the acidity of their wine, thereby influencing the flavour, aroma, and overall profile of their brandy.
Improving brandy distillates through better heat management in distillation
Gas management during distillation is a subtle yet powerful tool in crafting high-quality brandy. In Cognac production, so much emphasis is placed around all about the ‘gas curve’ – the careful modulation of gas pressure throughout the distillation cycle, which significantly influences the flavour and aroma extraction from the wine.
For others who distil using other methods (electric, steam) – the principles still apply even if the heating method doesn’t involve a direct flame.
Historically, for traditional Cognac distillation the process was naturally created by the ebbs and flows of a wood fire. Today, even with gas-fired alembic pot stills, this approach is meticulously replicated.
The key phase global brandy makers should look at in their own distillation tempo is the process is known as ‘mise au courant’, spanning the initial 2-2.5 hours of distillation.
During this phase, distillers adjust the gas to control the flow rate of the heads, making precise decisions crucial for the quality of the eau de vie. It’s not a case of switching on and incrementally raising the temp every 15 minutes… Nor taking it easy for the first bit and going full steam from there.
Cognac distillers employ either a ‘progressive’ or ‘rapid’ method of gas management. The progressive approach involves gradual adjustments in gas pressure throughout the distillation. Meanwhile the rapid method, used by houses like Hennessy, involves abrupt changes in gas pressure at specific points in the cycle.
Both methods significantly impact the character of the distillate.
Adapting gas management to modern stills
For distillers using more modern equipment, replicating the traditional gas curve can be challenging but not impossible. Here are some ways to achieve similar effects:
- Automated control systems: Modern stills often come with sophisticated control systems that can precisely regulate heat. Distillers can program these systems to mimic the traditional gas curve, using data from traditional distillation methods as a reference.
- Manual monitoring and adjustment. For those who prefer a hands-on approach, manually monitoring and adjusting the gas pressure can closely replicate the traditional method. This requires careful attention and understanding of how heat affects the distillation process.
- Consultation and collaboration. Working with experienced Cognac distillers or consulting with distillation experts can provide valuable insights into replicating traditional gas management techniques.
Optimising condenser cooling temperature
The cooling process in distillation, especially how the condenser is managed, also influences the quality of the final eau de vie. In Cognac production, this aspect is meticulously controlled, with distinct strategies employed for different stages of distillation.
We all know that the condenser cools the vapour produced in the pot still, converting it back into liquid form. It’s easy just to look at it in this performative, functional role – not as a way to shape flavour. But it does! Just ask whisky distillers about Worm Tubs and Shell and Tube condensers…
Cooling temperature management in Cognac distillation
In traditional Cognac distillation, different temperature settings are used for the first and second distillations.
During the first distillation, a lower temperature setting is used in the cooling tank. This results in a distillate that flows out at around 13˚C. In contrast, the second distillation, which refines the spirit and enhances its complexity, is typically set to a higher cooling tank temperature. The aim here is to allow the distillate to exit at around 18˚C – 20˚C, enabling certain esters and potential ethanal to evaporate.
It’s a minor detail but think by thinking through how much copper contact the distillate has, how they are making a heads cut, the desired flow rate and more – distillers can alter the profile of the eau de vie.
It’s an extra tool to harness, yet one that’s almost always overlooked by those with modern stills.
Improving brandy distillates by managing the ABV of Low Wines
The Alcohol by Volume (ABV) of low wines — the product of the first distillation in the Cognac process — significantly influences the character and quality of the final eau de vie.
Why? Because the ABV of low wines dictates the concentration of aromatic compounds that will be carried over into the final distillate.
A lower ABV in the low wines typically results in a spirit with greater aromatic width, as it allows for a more selective concentration of flavours and aromas during the second distillation. By contrast, a higher ABV tends to lead to a more robust spirit (and higher yield) but could also risk losing some of the subtler notes.
In Cognac, different houses have their own target ranges for the ABV of low wines, reflecting their unique house styles, ferments, and maturation plans. There’s quite a big difference between 27% abv and 33% abv…
Strategies for modern distillers
For distillers looking at ways to improve their distillates, here are some strategies to manage the ABV of low wines effectively:
- Precise monitoring: Use advanced technology to predict, monitor and control the ABV throughout the distillation process accurately. Set a target!
- Customised distillation practices: Develop distillation practices that suit the desired ABV range. Consider factors like the type of still used, the heating rate, and the duration of distillation. If you have a dephlegmator, consider how it can be used to fulfil the objective.
- Taste and adjust: Employ sensory evaluation to assess the impact of different ABV levels on the flavour profile. Make adjustments as necessary to align with the desired style. Look at this holistically, not just what it tastes like in that moment. How is it affecting flavour downstream?
Knowing when to recycle Heads and Tails, and when to discard
As with all spirits, the recycling of heads and tails — the initial and final fractions of the distillate — is a practice steeped in tradition and expertise.
Not doing implementing this practice is madness for those looking to making quality brandy. Simply put, it’s the single best place to improve the distillate that goes on for maturation.
That doesn’t mean everything other than the hearts cut needs to be thrown away. Many producers separate tails into two sections: one that gets redistilled and one that is discarded.
What does recycling heads and tails involve?
Heads, the first fraction of the distillate, contain higher alcohols and other compounds that can impart undesirable flavours if left in the final product. Tails, on the other hand, emerge at the end of the distillation and contain heavier, oilier compounds.
In Cognac, most houses recycle a portion of their heads and tails back into the subsequent wine batches for further distillation.
This recycling not only optimises the yield but also contributes to the complexity and depth of the final spirit. Most will work with around 8-10% of the total charge being made up of heads and tails.
If you are not doing this practice, start. It will immediately improve the distillate. If you are, look at your % volumes and how much is being recycled. Question it and check your thinking around why.
Improving brandy distillates by making precise cuts
For those who aren’t making cuts, or who are learning about the process of making great brandy – this part is for you!
The process of separating the heads, hearts, and tails during the second distillation is where the true skill of a brandy distiller is showcased. It requires a keen sensitivity to the subtle changes that occur during distillation. The precision in making these cuts determines the quality and character of the eau de vie.
The art of making cuts
The primary reason a heads cut is made in brandy, is to remove ethenal and other undesirable aromas, leaving as many desirable aromatic compounds as possible to then be captured in the hearts.
In France, the exact point of the cut varies between houses. For instance, Martell makes a significant heads cut for a lighter style, whereas Rémy Martin minimises the heads cut to retain their distinct character.
The size of the hearts cut is equally subjective. It typically begins when the ABV of the spirit at the flows off the still around 65% ABV (the heads starts around 70% and drops down). The transition to the tails, is marked by a slight soapiness and a change in flavour, indicating the start of a greater proportion of fatty acids.
The abv of when to make a tails cut is highly dependent on the amount of spirit that has been collected, the time it has taken, the way the still has been heated and more. Hard data aside – it’s most dependent on the flavour and what the master distiller wants. It’s subjective.
Mastering the precision in heads and hearts cuts requires a blend of sensory acumen, technical understanding, and experiential learning. By training and sensitising themselves to the subtle indicators during distillation, through making accurate cuts distillers can achieve a level of craftsmanship that elevates their brandy to the highest quality standards.
A few tips to hone your cuts…
- Taste and smell training: Regularly engage in sensory training exercises. Tasting and smelling different fractions of the distillate helps in developing a nuanced understanding of the evolution in flavour and aroma profiles.
- Batch analysis and comparison: Analyse and compare different batches to understand how the cuts influence the final product. Keeping detailed records of each distillation, including the points of cuts and the characteristics of the resulting eau de vie, aids in developing a more refined technique.
- Small scale experiments: Conduct small-scale distillation experiments to explore the effects of different cuts. This hands-on approach allows for a more experimental and intimate understanding of how subtle changes affect the spirit. It might create some wastage, but it’s a small price to pay for the long term gain.
- Mindfulness and patience: Being patient, focused, and mindful during the process is key. Paying close attention to the changes in smell and taste as the distillation progresses is crucial. You can’t rush improving your senses – it takes dedicated practice.
Improving brandy distillates by focussing on these common distillation issues
Most of the big ways you can improve the quality of the distillate have now been described. Some are easier said than done and progress is often incremental.
That said, most of the time where there is an actual issue and a borderline faulty product, there are five factors that frequently come up. If you are reading this having frantically googled for answers on why yours tastes awful, and not because you are looking for incremental gains – there is a fair chance one of these is your issue.
- Wine too rich in lees. A big decision brandy makers take is whether or not to distil on the lees (yeast cells leftover from fermentation). These contributes to the style of the finished cognac and can add texture and richness. However, distilling wine with excessive lees can lead to overheating and pyrolysis, negatively affecting the spirit’s flavour. Check yours.
- Poor control of heating cooling temperatures. Distilling too quickly can lead to poorly sorted spirits, with a lack of depth and complexity. Equally, inadequate management of the cooling process can result in the loss of crucial aromatic compounds and / or the retention of undesirable ones. If you are making Brandy in a warm climate, pay attention to these too closely.
- Inaccurate cuts. Imprecise cuts during distillation can lead to an imbalance in the final spirit. This leads to either too much emphasis on harsher heads or oilier tails.
- Excessive presence of heads and tails. Partly a continuation of inaccurate cuts, but also due to over recycling. Question whether you are allowing too much of the heads or tails into the final product and adjust accordingly.
- Poor cleanliness of the pot still and preheater. Residue build-up can affect the flavour and aroma of the distillate.
Patience and practice
By embracing Cognac’s time-honoured techniques and understanding the subtle artistry involved, distillers can significantly enhance their brandy’s quality.
We’ve highlighted the importance of mastering various aspects of distillation, from managing ethanol and ethanal levels, utilising malolactic fermentation, to precision in making cuts and controlling distillation temperatures. It underscores why it takes a long time to become a master distiller! There is a delicate balance required in each step.
While we also pointed out some of the most common issues, what all of these tips and tricks on improving brandy distillates lead to is the one unavoidable truth. There is no quick fix. No silver bullet. Great brandy is the result of a combination of factors, chief amongst them, the humility and patience to want to keep improving.
