Estella Zuleta Carmona: Brewing with Curiosity, Guided by Water

There’s something captivating about someone who approaches coffee with both curiosity and precision. Estella Zuleta Carmona from Colombia, is one of those individuals. Head of Coffee at ROR Coffee Solutions, Dubai, Estella brings a rare combination of technical understanding, sensory sensitivity, and genuine passion to the world of coffee. 

HUDES | Worldwide Digital Magazine for Manual Coffee Brewers

Her focus? Water—an often overlooked yet crucial element in brewing. In this conversation, we dive into her journey, her perspective on water chemistry, and her role as a sensory judge.

Estella Zuleta Carmona: Brewing with Curiosity, Guided by Water

HUDES: Estella, before we dive into coffee science, let’s start with your background.

Estella Zuleta Carmona: As I became more involved in the coffee community, my curiosity kept growing. I was fascinated by baristas and tasters, carefully observing how they conducted quality analysis. The sensory side of coffee always intrigued me, and the moment I was able to taste my own brews, something clicked I was hooked.

After completing my course, I set out to find a barista job in the nearest city, and from there, my journey in coffee took off. The rest, as they say, is history.

HUDES: Water plays a crucial role in extraction, yet many baristas and home brewers overlook it. What’s the biggest misconception people have about water in coffee?

Estella Zuleta Carmona: One of the biggest misconceptions about water in coffee is thinking that "filtered" automatically means "good for brewing." 

Many baristas and home brewers assume that if they’re using filtered or bottled water, they’re covered but that’s not always the case.

In reality, water needs the right balance of minerals to properly extract the coffee’s flavour compounds. 

Too much mineral content can cause a flat, tasteless cup, while too little (as in distilled or overly purified water) can result in a lack of character and muted attributes. It’s not just about purity it’s about composition.

Understanding water’s hardness, alkalinity, pH, and its specific mineral content (like calcium, magnesium and sodium.) can completely change how a coffee performs in the cup. That's why I always say: water isn’t just a brewing ingredient, it’s your main extraction tool.

HUDES: If someone doesn’t have access to specialized water filtration systems, what’s the simplest way they can improve their brewing water?

Estella Zuleta Carmona: If someone doesn’t have access to a specialized water filtration system, the simplest way to improve their brewing water is to use clean, neutral tasting water that contains a balanced mix of minerals especially calcium, magnesium, less sodium but not 0, These minerals help extract and carry flavors from the coffee into the cup.

Avoid using distilled or demineralized water, as it lacks the necessary minerals for proper extraction, which can result in flat or weak brews. 

On the other hand, water that is too hard (with excessive mineral content) can lead off and muddled flavors.

An easy way to improve brewing water at home is by using a basic water filter to reduce chlorine and unwanted tastes and then blending it with a small portion of natural mineral water that contains both calcium and magnesium. 

This can help create a more balanced water composition that supports sweetness, clarity, and overall better extraction.

HUDES: Have you ever experienced a moment where water chemistry completely changed your perception of a coffee?

Estella Zuleta Carmona: Yes, there was a day I was running an experiment, brewing with different water compositions to better understand how minerals specifically ions interact with coffee and impact the final cup. 

I was preparing for a water talk at ZHAW in Switzerland, and I wanted to explore how small adjustments could influence both flavour and physical sensation and how concentrations can make the ion inhibitor or enhancer.

During one of the brews, I got a result that really stood out: the coffee had a medium-heavy body, a velvety mouthfeel, and at the same time, incredible clarity in the flavors. 

I remember feeling genuinely happy, because personally, I enjoy coffees where the physical sensations like mouthfeel and texture are as clear and defined as the flavor notes. It was a perfect example of how water chemistry can bring balance and precision to a cup.

That moment reminded me that water isn’t just functional it’s transformative when you understand how to work with it.

HUDES: As a sensory judge, how do you balance technical extraction principles with the subjective nature of taste?

Estella Zuleta Carmona: As a sensory judge, balancing the technical aspects of coffee extraction with the subjective nature of taste is an ongoing and fascinating challenge. 

I rely on a solid foundation of technical knowledge understanding how factors like brew ratio, grind size, water composition, and time influence the cup. 

These principles provide a consistent framework that helps me assess whether a coffee was extracted properly and give context to what I experience in the cup.

At the same time, I recognize that taste is deeply personal and subjective. Even though I’m trained to detect and describe flavors using a shared sensory language, I’m constantly aware that no two palates are the same. 

This awareness keeps me grounded and reminds me to be open, especially when encountering coffees with profiles that might differ from my preferences or usual benchmarks.

The key is to integrate both sides technical and sensory. I don’t let numbers alone determine quality, and I don’t let personal bias override the brewing facts. 

Instead, I listen to the cup: how it speaks through aroma, texture, acidity, balance, and aftertaste. I try to understand what it’s telling me about the process behind it. This balance helps me give constructive, meaningful feedback that supports both objectivity and the emotional experience of tasting coffee.

Ultimately, judging is about fairness, clarity, and sensitivity. I strive to be calibrated not only in flavor descriptors, but also in my mindset remaining consistent, yet open to surprise.

HUDES: What are some key sensory skills that coffee professionals should develop to better understand extraction?

Estella Zuleta Carmona: From my experience, there are a few key sensory skills that every coffee professional should develop to truly understand and evaluate extraction:

First, calibrated taste recognition is essential being able to consistently identify sweetness, acidity, bitterness, and balance helps you detect when a coffee is under or over-extracted. This isn’t just about naming flavors, but about understanding their intensity, clarity, and how they interact in the cup.

Second, aroma memory and identification plays a huge role. Developing your olfactory memory helps you track how different brewing methods or changes in grind size affect the volatile compounds and the overall aromatic experience of the coffee.

Third, mouthfeel sensitivity is often overlooked, but it tells you a lot about the quality of extraction. Learning to identify differences in body, texture, and tactile sensation helps assess whether you’ve extracted the right compounds  too much dryness or harshness, for example, may signal over-extraction or poor water chemistry.

And finally, aftertaste awareness  the length and quality of the finish  is a powerful indicator of both quality and balance. A clean, lingering aftertaste usually points to a well-extracted and well-processed coffee.

All of these skills improve with focused, repetitive practice. Cupping regularly, using sensory kits, and comparing brews side by side with intentional variable changes will sharpen your sensory perception and deepen your understanding of what’s happening in each extraction.

HUDES: How do you personally train and maintain your sensory accuracy over time?

Estella Zuleta Carmona: To maintain and improve my sensory accuracy over time, I focus on a mix of structured training and daily habits that keep me sharp.

I cup coffees regularly with my team, not just to evaluate quality, but to recalibrate my palate. I do blind tastings often  comparing different origins, processes, or roast levels  and I take notes to track how my perceptions evolve. I also like to revisit coffees after they rest or age, because it forces me to stay aware of how time affects flavor.

Aroma training is part of my routine too. I use kits like Le Nez du Café to refine my recognition of specific aromatic compounds. Even outside of coffee, I pay attention to smells and tastes in food, wine, fruits, or spices  everything adds to my sensory memory.

Another important part is calibration with other professionals. Judging competitions or cupping with other sensory experts helps me compare and challenge my assessments. It keeps me grounded and helps avoid personal bias.

Lastly, I take care of my health staying hydrated, avoiding strong flavors before cupping, and even usually as  I don’t tolerate high levels of spicy  and giving my palate rest when needed. It might sound simple, but consistency and care are what make the biggest difference in keeping your sensory skills sharp over time.

HUDES: In recent years, we’ve seen an explosion of new dripper designs, each claiming to enhance extraction in different ways. What are your thoughts on this trend?

Estella Zuleta Carmona: I find the rise of new dripper designs really interesting it reflects how much curiosity and innovation there is in the coffee community. 

Each design brings subtle changes in how water flows or heat is retained, and sometimes that can slightly influence the way a coffee tastes. 

From my experience, some drippers can help showcase specific aspects of a coffee, like clarity or balance, but at the end of the day, many of them are just small variations of the same idea.

What really makes the difference is how we use them. The fundamentals still matter the most: good coffee, the right grind size, water quality, and a consistent technique. 

I've tried several of these new designs, and while some do offer a different feel or flow rate, the biggest improvements often come from refining the brewing process, not just changing equipment.

To me, it's great to have options, but I see many of these brewers more as tools to explore rather than game-changers. It’s the experience of testing, adjusting, and learning that deepens my understanding of coffee not necessarily the tool itself.

HUDES: Do you think these new drippers significantly impact extraction, or do fundamentals like water chemistry and grind size play a bigger role?

Estella Zuleta Carmona: From my experience, while some new drippers can influence certain aspects of the brew like flow rate, agitation, or heat retention the fundamentals still carry the most weight. 

Things like water chemistry, grind size, coffee quality, and technique consistently have a far greater impact on the final cup than the brewer design alone.

Many of the new drippers feel more like refinements than revolutions. They can offer interesting ways to control variables, but they don't override the basics. If your grind size is off, your water isn't right, or your pouring technique is inconsistent, even the most advanced dripper won’t save the brew.

That said, these designs are valuable for learning and experimentation. 

They help us better understand how different factors interact, but in terms of truly elevating cup quality, fundamentals always come first.

HUDES: Have you tested any recent dripper innovations that truly stood out to you?

Estella Zuleta Carmona: The Orea dripper has truly impressed me with its design and how it transforms the brewing process. From a hands-on perspective, the flat-bottom, geometric shape ensures an even bloom, which sets the stage for a balanced extraction. 

When brewing with it, I’ve noticed how it reduces channeling, allowing for the water to interact more evenly with the coffee grounds. 

This means no sudden weak spots in the brew, which can often lead to uneven flavors. The result is always a smooth, clean cup with a well-rounded flavor profile, where each note feels more integrated and pronounced.

What really stands out is the consistency. It’s one of those drippers that, once you dial it in, delivers excellent results with less effort. It’s perfect for those looking to achieve a controlled, precise extraction every time. 

For someone who’s spent a lot of time experimenting with different drippers, the Orea feels like a solid choice for a reliable, high quality cup of coffee without any unnecessary complexity.

HUDES: What does your role as Head of Coffee at ROR Coffee Solutions involve?

Estella Zuleta Carmona: As Head of Coffee at ROR Coffee Solutions, Dubai, my role is multifaceted, focusing on both the technical and creative aspects of coffee. I oversee the entire coffee-related operations, which involves managing the coffee sourcing, quality control, and product development processes. My responsibilities include in general include :

Sourcing and Partnering with Suppliers: I work closely with our suppliers, from coffee farms to roasters, ensuring we have access to high-quality beans that meet our standards. This includes visiting farms, maintaining strong relationships, and making sure we're sourcing sustainably.

Quality Control and Sensory Evaluation: I lead the quality control process, and together with my team constantly tasting and evaluating different batches to ensure they align with our high standards. This includes overseeing the sensory analysis of coffee, where I rely on our expertise in cupping, brewing, and analyzing the coffee’s flavor profile.

Training and Development: I design and lead training programs for our team and clients. This includes everything from barista training and brewing techniques to in-depth workshops on water chemistry, coffee profiles, roasting and green beans and other technical aspects. I'm passionate about educating both professionals and enthusiasts to improve their understanding of coffee and their skills.

Product Development: I'm also responsible for innovating and developing new coffee products. This could mean designing new blends, experimenting with different brewing methods.

Collaboration and Industry Representation: I represent ROR Coffee Solutions at industry events and competitions. This includes judging at coffee competitions, speaking at conferences, or collaborating with other industry leaders to stay at the forefront of coffee innovation.

Operational Oversight: I lead  a team, making sure that day-to-day operations run smoothly. This involves managing the workflow of roasters, baristas, and quality control teams to maintain consistency across the board.

In essence, my role combines a deep technical understanding of coffee with a creative and educational approach, ensuring that ROR Coffee Solutions delivers high-quality coffee experiences to both our team and our customers.

HUDES: What’s the biggest challenge in coffee extraction today?

Estella Zuleta Carmona: One of the biggest challenges in coffee extraction today is achieving consistency while honoring the complexity of the coffee especially as we work with higher quality beans, more advanced processing methods, and a wider range of brewing equipment.

Coffees are becoming more diverse in their flavor potential, thanks to innovations at origin like controlled fermentations, experimental drying techniques, and selective harvesting. But that also means that extraction has to be even more precise. Small changes in grind size, water composition, temperature, or even the pouring technique can drastically shift the cup profile sometimes in a good way, sometimes not.

Another huge challenge is understanding water as an active ingredient. Many baristas and brewers still underestimate how crucial mineral composition is to how coffee extracts. It’s not just about having "filtered water" anymore it’s about dialing in the right balance of calcium, magnesium, and even sodium or potassium to emphasize sweetness, mouthfeel, or brightness depending on the coffee. If your water is off, even the best roast won’t taste right.

Also, as technology becomes more accessible think automated brewers, scales with flow tracking, and refractometers there’s this illusion that perfect extraction is just about numbers. But sensory evaluation still matters deeply. You can hit a textbook TDS or extraction yield and still have a flat or unbalanced cup.

HUDES: Do you see any emerging trends in how professionals approach water chemistry in brewing?

Estella Zuleta Carmona: Absolutely there’s a noticeable shift happening in how professionals approach water chemistry, and it's no longer just about hitting the recommended parameters. The emerging trend is moving toward a more intentional, tailored approach, where water is seen not just as a medium for extraction, but as a tool to shape the sensory profile of each coffee.

Professionals are now customizing water recipes depending on the coffee’s origin, processing method, roast level, and even brewing style. For instance, lighter roasts or anaerobic coffees might call for water with higher magnesium to boost perceived acidity and clarity, while naturals or darker roasts might benefit from more calcium to enhance mouthfeel and sweetness is like playground.

There's also growing interest in using specific ions to highlight or suppress certain attributes. For example, some brewers experiment with low bicarbonate waters to avoid buffering acidity, or use small amounts of sodium or potassium to round off bitterness and enhance sweetness. This kind of fine-tuning wasn’t widely practiced just a few years ago outside of competition circles but now it’s becoming more mainstream among quality-focused cafés and roasteries.

Another trend is a move toward modular water building. Professionals are using distilled or reverse osmosis water as a base and adding mineral concentrates in precise amounts. This not only gives them control, but also makes it easier to replicate and scale recipes across multiple locations or brew bars.

Finally, I see a strong shift toward sensory-led water adjustment. Instead of blindly following lab data, brewers are starting to cup or brew multiple waters side by side, and choose based on taste, not just numbers. 

It’s a more holistic and flexible way to work with water and I think it’s pushing the industry into a more nuanced, exciting direction.

HUDES: If you could conduct a dream experiment in coffee and water chemistry, what would it be?

Estella Zuleta Carmona: If I could conduct a dream experiment in coffee and water chemistry, it would focus entirely on how different water compositions influence brewing dynamics and sensory outcomes.

I’ve always dreamed of working in a fully equipped coffee chemistry lab, where I could precisely manipulate ion concentrations and study their effects on extraction. This experiment would involve brewing the same coffee with varied mineral compositions to observe how each component alters flow rate, solubility, and flavor perception.

Beyond just measuring TDS and extraction yield, I’d want to analyze how different water formulations affect the brewing process itself flow resistance, turbulence, and even temperature stability. I’d also compare how these changes manifest in the cup as the coffee cools, identifying which water compositions create more stable, expressive brews over time.

The ultimate goal would be to develop method-specific water formulations that help baristas and brewers optimize extraction for different brewing techniques. This could lead to a more refined approach to water chemistry one that moves beyond general recommendations and towards precisely tailored water for each brewing method.

Working in a lab dedicated to brewing-focused water research would be a dream come true bridging science, sensory analysis, and hands-on experimentation to uncover the most effective ways.

HUDES: What’s one piece of advice you wish more coffee professionals knew about water and extraction?

Estella Zuleta Carmona: One key piece of advice I wish more coffee professionals understood is how subtle variations in water chemistry can have a significant impact on the extraction process. It's not just about the water being clean its mineral content, pH, and conductivity play crucial roles in enhancing or inhibiting certain flavors in the coffee. 

Understanding how different ions like calcium, magnesium, and bicarbonates interact with the coffee grounds can help create a more consistent and refined extraction, allowing for the full potential of a coffee to shine. If more professionals embraced this, it could lead to better, more customized coffee experiences across the board. 

HUDES: Lastly, when you’re not thinking about coffee and water, what do you enjoy doing?

Estella Zuleta Carmona: When I'm not thinking about coffee and water, I really enjoy studying law, capturing the beauty of sunsets through photography, and losing myself in the peaceful moments they bring. 

I also love spending time by the sea, listening to the waves and soaking in the calm. Outside of that, I focus on personal growth and learning whether it's diving deeper into law, building meaningful connections with others, or hitting the gym to stay active and focused. (Hudes magazine)