The road to the World Brewers Cup is built on countless decisions.
Coffee selection. Roast development. Brewing technique. Presentation. And increasingly, water design.
As the reigning 2026 Japan Brewers Cup Champion, Wataru Iidaka earned his place on the world stage through a thoughtful and deeply personal approach to competition. In just a few weeks, he will represent Japan at the World Brewers Cup Championship in Brussels, bringing with him a philosophy centred around clarity, intention, and meaningful connection.
For Wataru, Brewers Cup is more than a brewing competition. It is a platform to communicate ideas, values, and experiences through coffee. We spoke with him about competition, water design, and how APAX LAB helped him bring his vision to life.
1. Tell us more about the Brewers Cup. What makes this competition special to you and why did you decide to compete this year?
The Brewers Cup is more than a competition about brewing delicious coffee.
It is a stage where I can express the producers' passion, my roasting philosophy, brewing techniques, and even my personal values through a single cup.
What makes it especially meaningful to me is the opportunity to share why I made each choice.
Coffee has the power to connect people.
That is why I find this stage so special—it allows me to share the possibilities and value of coffee with others through a meaningful and memorable experience.
Winning alone was not enough to give me a reason to continue in coffee.
That is why I decided to compete again this year—to share that message through coffee.
2. Water quality is crucial in brewing. How did it impact your approach to the competition?
I see water not simply as a brewing medium, but as a tool for designing flavour.
The theme of my routine was "clear and easy-to-understand complexity."
With that in mind, I designed my water to express the coffee's floral aromatics, fruit character, and sweetness as clearly as possible.
Before creating my recipe, I first asked myself what kind of experience I wanted to deliver. Then, I worked backwards from that experience to choose the water that would best bring it to life.
3. How did you first hear about APAX LAB, and what made you choose our products to craft your competition water?
I first learned about APAX LAB through conversations and exchanges with competitors and coffee professionals from around the world.
What attracted me most was that APAX LAB goes beyond simply adjusting TDS or hardness.
It allows you to design water based on a much more important question:
"What kind of flavour experience do you want to create?"
In competition, consistency and clarity of intention are essential.
APAX LAB became a valuable partner in helping me express the flavours I envisioned with greater precision and confidence.
4. In what ways did the mineral concentrates help you achieve the best expression of your coffee and contribute to your win?
Minerals do not create flavour; they help reveal the flavours that already exist within the coffee.
The coffee I chose had beautiful floral notes and a transparent, elegant sweetness.
By carefully designing the mineral composition of the water, I was able to express those characteristics with greater clarity and precision.
As a result, I believe I was able to communicate the flavour story I wanted to share with the judges more accurately and effectively.
5. Which APAX LAB profile is your favourite, and why?
My favourite profile is around 50 ppm.
The reason is that it allows me to express the delicate floral aromatics and clarity of Geisha in a very natural way.
While I always pursue complexity in a cup, I also believe that complexity should be easy to understand and enjoy.
For me, around 50 ppm is where that balance is expressed most beautifully.
6. What coffee did you choose for your competition routine, and why was it the perfect fit for your approach?
For the Japan Brewers Cup, I chose two Geishas from Panama.
One offered vibrant fruit character and sweetness, while the other brought exceptional clarity and floral elegance.
I believed that by combining these different personalities, I could create a richer and more meaningful coffee experience.
This idea was closely connected to the theme of my presentation.
When different people, perspectives, and values come together, they have the potential to create something entirely new and valuable.
7. What was your winning water recipe with APAX LAB, and how did it influence the final cup?
My water recipe was designed around a target of approximately 50 ppm.
I used:
- 1.7g TONIK
- 1.0g JAMM
- 1.3g LYLAC
Diluted into 2.4L of Zero Water.
This water profile helped me express aromas reminiscent of white and yellow flowers, bright citrus-like acidity, and a long-lasting sweetness in the cup.
8. What is your motto, or favourite quote when it comes to coffee competition?
A phrase that is very important to me is:
日進月歩 (Nisshin Geppo)
It is a Japanese expression that means:
"Continuous growth and improvement, day by day."
I believe competition is the same. Victory lasts only for a moment, but growth continues every single day.
That mindset is what keeps me motivated to keep learning, improving, and moving forward.
9. For those new to crafting their own water for filter coffee, what advice would you give them?
My advice is not to overcomplicate things at the beginning.
Start by using the same coffee and simply compare different water recipes.
This will help you experience firsthand just how much water can influence flavour.
And rather than focusing only on numbers, ask yourself a more important question:
"What kind of experience do I want to create?"
Water is a tool for expressing the true character of a coffee.
That is why I believe it is important to start with your ideal cup in mind and then work backwards to design the water that helps bring that vision to life.
Final Thoughts
Throughout this interview, one idea appears again and again: clarity.
For Wataru, water is not simply a technical variable. It is a creative tool used to translate a complex vision into a clear sensory experience.
That philosophy helped him secure the title of 2025 Japan Brewers Cup Champion and will accompany him to Brussels as he prepares to represent Japan on the world stage.
