For many industry professionals, the World Barista Championship (WBC) is a global platform for competitors to showcase the latest trends and innovations in specialty coffee. These can include new coffee species and varieties, as well as unique ways of preparing and extracting coffee beverages.
In his winning 2022 WBC performance, we saw Australian competitor Anthony Douglas use one of the latter for his milk course category. During his routine, Anthony described a process called cryodesiccation (which is similar to freeze drying) and explained that he processed his milk using this technique.
Anthony mentions that cryodesiccation helped to enhance the natural sweetness and creaminess of his milk, and ultimately created a higher-quality beverage and overall sensory experience.
So how exactly does this process work, and could it have an influence on the wider specialty coffee sector?
To find out, I spoke with two coffee professionals. Read on to find out what they had to say.
You may also like our article introducing extract chilling in coffee.
Understanding the cryodesiccation process
Cryodesiccation (also known as freeze drying or lyophilisation) is essentially a low temperature dehydration process. It’s mainly used in food, beverage, and pharmaceutical industries to prolong shelf life, while still maintaining quality.
In fact, the vast majority of instant coffees are freeze dried. This helps to create a more convenient product; however, the process still preserves some of the coffee’s flavours and aromas.
Broadly speaking, there are four main stages to the cryodesiccation process: pretreatment, freezing, primary drying, and secondary drying. Overall, the process involves the application of low temperatures and various different pressures to remove moisture.
Anthony Douglas is the training manager at Axil Coffee Roasters, as well as the 2022 World Barista Champion. He explains how he produced cryodesiccated milk for his WBC routine.
“Firstly, we filled metal trays with milk and then froze them,” he says. “We then placed the trays inside a vacuum chamber.
“We lowered the pressure inside the chamber and applied gentle heat underneath the trays [over a 24-hour period],” he adds. “This causes water in the frozen milk to turn into a vapour, rather than a liquid, as it thaws, which leaves behind a powder-like substance.
“Because the process uses lower temperatures, the milk still retains a lot of its natural flavours, which are then concentrated,” he continues.
How does the process affect flavour and mouthfeel?
In his winning 2022 WBC routine, Anthony mentions that the cryodesiccated milk powder he created was concentrated by about 900 times. He explains that he then recombined 30g of the powder with 300g of fresh milk to “double the concentration of sugars, fats, and proteins”.
Ultimately, this helped to make his milk course beverages taste much sweeter and gave them a creamier mouthfeel, as well as possibly helping to produce better-quality latte art because of the higher amount of proteins in the milk.
“We were already using high-quality milk from Riverina Fresh, but we were struggling to create consistent-tasting milk course beverages,” Anthony explains. “This led us to try cryodesiccation.
“We chose to use this process in my WBC routine because it didn’t change the flavour of the milk – instead, it concentrated all of its desirable aspects, such as sweetness and creaminess,” he adds.
“When combined with coffee – specifically the anaerobic natural Sidra variety from El Diviso in Colombia – it resulted in a sweet and lush milk-based drink which helped to enhance and balance the coffee’s flavours with certain qualities of the milk,” he continues.
Have similar processes been used at the WBC before?
Although no previous WBC competitors have used cryodesiccated ingredients in their routines before Anthony, some have used similar processes for milk.
It’s believed that Canadian competitor Ben Put was the first person to use such a process at the 2017 WBC, when he concentrated his milk using freeze distillation. Morgan Eckroth, who placed second at the 2022 WBC, also used freeze-distilled whole milk in their routine to further enhance the sweetness of the coffee they served.
Freeze distilling is somewhat similar to cryodesiccation. The process works by partially freezing a liquid and then removing some of the frozen segments to produce a more concentrated liquid. With milk, this means that it will taste sweeter, richer, and creamier as more of its water content is removed.
Anthony explains the differences between the two processes.
“Different compounds thaw at different rates, so when you create freeze-distilled milk, not all of the compounds will concentrate at an even rate,” he tells me. “In my experience, you also have to get the timings and temperature right to ensure you can thaw the milk at the same rate each time you carry out the process.
“However, with cryodesiccation, milk reduces it to a powder-like substance which is consistently concentrated every single time,” he adds. “This process also increases shelf life, so when you want to use the powder, you can combine it with fresh milk at the concentration which works best, which for us was 1.8 times concentrated.”
But these processes are not just used for milk – some competitors have also carried out similar techniques with other ingredients.
Hugh Kelly is the training manager and head of Research & Development at ONA Coffee. He is also a three-time Australian Barista Champion.
He tells me about the freeze drying method, and how he has incorporated this process in several of his WBC routines – and has even used it for espresso.
“I have used freeze-dried ice cream, lychee, and peach in some of my signature drinks over the years,” he explains. “The process has a significant impact on mouthfeel and flavour, but it also usually allows for fresher-tasting fruit notes compared to dried fruit notes, which are usually more caramelised.
“When freeze-dried ingredients are ground into a powder and mixed with wet ingredients, it creates a very consistent product, in terms of water and Brix content,” he adds. “It’s also very easy to infuse the powder into liquids.”
What factors do you need to consider when using cryodesiccated milk?
For Anthony, milk concentration is just as important as any other extraction variable.
“It’s an extra variable to consider alongside dose, yield, and total extraction time,” he says. “It gives you more freedom to express the flavours in coffee.”
As it is a relatively new process to specialty coffee, there are understandably many factors to take into account when using cryodesiccation.
“This technique is still new to us, so we are still finding our way around it,” Anthony says. “The most important thing is to not over-concentrate your milk, as this can overpower the flavours of the coffee.”
This is because the sweetness and richness of the milk becomes much more intense, which can mask more delicate flavour notes in certain coffees. Ultimately, the enhanced sweetness and creaminess of the milk still needs to complement whichever coffee you decide to use.
“The different concentrations of milk also allow you to explore different extraction styles,” he continues. “For example, cryodesiccated milk which is more concentrated can work better with espresso which is extracted using a higher coffee-water ratio.”
For context, espresso is usually extracted at a 1:2 ratio – meaning one part coffee to two parts water.
When it comes to steaming cryodesiccated milk, Anthony says that the method is largely the same as preparing regular milk.
“However, the higher concentration of fats and proteins in the milk will improve the quality of microfoam, as well as how you experience the coffee’s flavours,” he says.
Although Anthony explains that he has only used cryodesiccation with whole milk, he believes that the process could be used with various different types of milk – including plant-based options.
Will we see this process more in competitions and coffee shops?
Firstly, it’s important to note that in order to create cryodesiccated milk, you certainly need to invest in costly equipment – which undoubtedly would also take up a significant amount of space.
Ultimately, this means that for many coffee shops and World Coffee Championship competitors, cryodesiccation may not be a feasible option.
Hugh believes that although competitors might continue to use similar techniques as part of their routines, most coffee shops are unlikely to adopt these practices.
“Using concentrated milk makes more sense for competitors than it does for coffee shops because it creates more impact for every sip of coffee you drink,” he tells me. “But if you drink too much of it, it could be off-putting, so finding the right balance and intensity is key.”
He points that using freeze-dried milk could be a more accessible option for some coffee shops.
“However, the main issue could be having access to high-quality freeze-dried milk,” he says. “There are few freeze-dried milk powders which are specifically designed for coffee because many of them don’t have the right ratio of fats, sugars, and proteins.”
Innovation is an integral part of the WBC, and milk processing is also a part of this – it allows competitors to express different flavours and textures in coffee.
“Trying milk-based beverages in new ways can significantly improve the overall sensory experience, which can be a truly unique selling point for a coffee shop, or focus of a competitor’s routine,” Hugh concludes.
However, considering the time, space, and equipment required for processes like cryodessication, it’s unlikely that it will become a widespread change for coffee shops any time soon.
Enjoyed this? Then read our article exploring the evolution of milk foaming technology in the coffee industry.
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