How much of an extraction should you chill?

Understanding 'Extract Chilling'

When it comes to brewing coffee, every step in the process can significantly impact the final flavour profile. One innovative technique that has been gaining attention is extract chilling, particularly with tools like the Paragon Espresso. But how much of an extraction should you chill?

In this article, we’ll explore the benefits of chilling only a portion of your coffee extraction, the potential drawbacks of chilling more, and when longer chilling times might be beneficial.

Extract chilling is a method used to preserve the volatile aroma compounds that are released during the coffee brewing process. These compounds are responsible for the rich flavours and aromas that make coffee so delightful. By chilling the extraction, you can capture and retain these compounds, enhancing the overall taste experience.

The origins of this technique come from research conducted by researchers at Coffee Excellence Center at Zurich University (ZHAW), as they were exploring the impact of brew temperature on the volatile aroma compounds in coffee. As part of this research, Prof. Chahan Yeretzian and his team discovered a link between heat and volatile aroma compound loss in coffee.

The extract chilling method was first publicly introduced by Hugh Kelly of Nucleus Coffee Tools and ONA Coffee in the 2021 World Barista Championship. He extracted espresso over a frozen metal cube before allowing the shots to cool down. In his routine, he explained that this extraction method helps to preserve the flavour compounds in the coffee and heighten sweetness in particular. This was an extension of previous chilling techniques in coffee preparation, such as pre-chilling serving vessels or chilling the portafilter before extraction.

The key to successful extract chilling lies in understanding which part of the extraction to chill. Research and experimentation have shown that chilling only the first 20-40% of the extraction yields the best results. This initial portion contains the highest concentration of volatile compounds, making it the most flavourful part of the brew.

Benefits of chilling a portion of the extraction

Research done in collaboration with ZHAW shows that chilling the first portion of coffee extraction has the most benefit. Firstly, it helps in flavour preservation. The first part of the extraction is where the most volatile aroma compounds are released. By chilling this portion, you can capture these delicate flavours before they evaporate, resulting in a more aromatic and flavourful cup of coffee.

Secondly, it enhances complexity. By focusing on chilling the initial extraction, you allow the rest of the brew to develop naturally. This balance between chilled and un-chilled portions creates a more complex and nuanced flavour profile, highlighting the unique characteristics of the coffee beans.

Lastly, it improves balance. Chilling only a portion of the extraction helps maintain the balance of flavours. Over-chilling can lead to a muted taste, while the right amount of chilling preserves the coffee’s vibrancy and depth.

The role of Paragon and Paragon Espresso in extract chilling

The Paragon and Paragon Espresso tools are at the forefront of extract chilling technology, designed to enhance the coffee brewing experience by preserving the delicate aroma compounds that define a coffee’s flavour profile. These tools are engineered to capture and retain the volatile compounds released during the initial stages of extraction, ensuring that each cup of coffee is as aromatic and flavourful as possible.

The Paragon is a versatile tool that utilizes patented extract chilling technology, with an innovative and award-winning design that allows it to accommodate various filter coffee brewers and vessels – making it an ideal choice for coffee enthusiasts who enjoy experimenting with different brewing methods. The Paragon’s chilling rock, a core component of the system, is constructed from food-grade stainless steel and coated with durable titanium. This design ensures even and rapid chilling, capturing up to 40% more key aroma volatile molecules than an identical brew without chilling.

Similarly, the Paragon Espresso is specifically designed for espresso brewing. It features smaller chilling rocks that fit seamlessly under the group head of an espresso machine, allowing for efficient chilling without disrupting the workflow. The high-density liquid-filled core of the chilling rocks provides greater thermal capacity, maintaining colder temperatures for longer periods. This ensures that the most volatile aroma compounds are captured during the initial extraction, resulting in a more aromatic and flavourful espresso.

Both the Paragon and Paragon Espresso tools are designed to chill only a portion of the extraction, aligning with the benefits of flavour preservation, enhanced complexity, and improved balance. By focusing on the initial 20-40% of the extraction, these tools allow the rest of the brew to develop naturally, creating a harmonious and nuanced flavour profile. The Paragon and Paragon Espresso empower coffee lovers to explore the full potential of their coffee beans, offering a unique and elevated brewing experience.

Potential problems with chilling more

While it might be tempting to chill the entire extraction, doing so can lead to several issues. One potential problem is the loss of balance. Chilling too much of the extraction can result in a loss of balance. The later stages of the extraction contain different compounds that contribute to the coffee’s body and sweetness. Over-chilling can suppress these flavours, leading to a less harmonious cup.

Another issue is muted flavours. The process of chilling can mute some of the more subtle flavours that develop later in the extraction. This can result in a cup that lacks the complexity and richness that coffee enthusiasts seek.

Additionally, chilling the entire extraction can also affect the mouthfeel of the coffee. The texture and body of the brew may be compromised, leading to a less satisfying drinking experience.

When longer chilling times might be beneficial

While chilling only a portion of the extraction is generally recommended, there are instances where longer chilling times might be beneficial. Coffees with higher brew ratios, for example, may benefit from extended chilling. These coffees often have a more concentrated flavour profile, and chilling a larger portion can help balance the intensity and highlight the nuanced flavors.

Experimenting with different chilling times can also be advantageous when working with specific coffee beans or brewing methods. Some beans may have unique characteristics that are enhanced by longer chilling, offering a different taste experience.

Finding the right balance

The key to successful extract chilling is finding the right balance for your taste preferences. While research suggests chilling 20-40% of the extraction, it’s important to experiment and adjust based on the specific coffee beans and brewing method you’re using.

Experimentation is crucial. Try chilling different portions of the extraction to see how it affects the flavor profile. You may find that certain beans or brewing methods benefit from slightly more or less chilling.

Ultimately, the best approach is the one that suits your personal taste. Some coffee lovers may prefer a more pronounced chilled flavour, while others might enjoy a more balanced cup. As with any aspect of coffee brewing, continuous learning and experimentation are key. Stay open to trying new techniques and adjusting your approach based on the results.

In general, chilling a portion of your coffee extraction can significantly enhance the flavour and aroma of your brew. By focusing on the initial 20-40% of the extraction, you can capture the most volatile compounds while maintaining a balanced and complex flavor profile. However, it’s important to experiment and find the right balance for your taste preferences, especially when dealing with higher brew ratios.

For more information, browse our videos on Extract Chilling via our YouTube Channel.