Writer Kim Jin-ho's Water and Health Stories (63) Water and Coffee, the Oversight in What Seems Obvious

Café Competitiveness Begins with Water

In our daily lives, we take clean water for granted. Most homes are equipped with 3-4 stages of water purification systems, and homes with children or pets are even more sensitive to water quality. Drinking purified, clean water is no longer a 'choice' but a 'basic necessity.'

But what about coffee? A cup or two of coffee a day has become the norm, and it has now transcended being a simple beverage to become an important presence that adds comfort and rhythm to our daily lives. Yet, despite knowing that 98% of coffee is 'water,' many people fail to apply this fact to actual café operations and quality management.

The Most Important Ingredient Cafés Are Missing

Many cafés carefully select quality coffee beans, invest in expensive coffee machines, and put effort into perfecting the taste of coffee. Baristas meticulously adjust roasting, extraction temperature, and grinding fineness. However, there is less interest than expected in 'water,' which is the starting point of all these efforts.

In reality, most cafés filter water using only a single carbon filter. Water that has merely removed or reduced chlorine content without removing contaminants from water pipes goes directly into the coffee machine and into customers' cups. This is merely a level of 'primary filtration.'

The results are clearer than expected. The beans are good, but the coffee tastes bland, astringent, has sharp acidity, or strong bitterness, and so on. Is it the coffee machine's fault? The beans' fault? No. If the water quality itself is poor, even the best beans and coffee machine cannot properly extract their flavors.

The Key to Coffee Taste Begins with Water

Good water is not simply water free of impurities. It must be water with components suitable for coffee.

First, it is necessary to consider mineral content. In particular, magnesium plays a key role in bringing out the sweetness of coffee and establishing a savory taste and balance. When minerals are lacking, the sweetness of coffee becomes unclear, leaving a bland or astringent taste.

pH (hydrogen ion concentration) is also important. Alkaline water gently moderates coffee's acidity and reduces excessive bitterness. Additionally, water particle size also affects coffee extraction power and mouthfeel. The more finely water is purified, the more evenly coffee bean components are extracted, and a smoother texture emerges.

Ultimately, coffee is a beverage completed by the harmony of beans, water, and temperature. If any one of these is lacking, the quality of coffee taste that customers experience will inevitably suffer.

Sustainable Café Operations, Determined by 'Water'

Now, water has become an indispensable element when discussing the quality of a single cup of coffee. The problem is that this is not limited to mere 'taste.'

Today's customers are far more sensitive than before. Beyond simple taste, they look at the source and quality of ingredients, hygiene, and sustainability all together. In such an era, 'water' can become more than a simple raw material—a symbolic element that shows how a café approaches both customers and coffee.

Furthermore, when coffee taste is maintained consistently, customer repeat visits increase, and bean consumption can be reduced. Ultimately, improving water quality leads not only to improved customer satisfaction but also, in the long term, to securing sustainable competitiveness that maintains café sales and profitability.

Specialty coffee shops and large café chains that lead in coffee taste are currently adopting and using mineral maker water purification filter systems optimized for coffee extraction. This should be viewed not simply as equipment investment but as a café's philosophy and competitive strategy.

Now, Café Water Must Be Checked First

There are actual reviews stating that just by changing a single water purification system, coffee taste changed. Fresh sweetness, soft texture, clean finish—customers feel this difference without even being told, and they return their empty coffee cups.

Water may occupy a small proportion of coffee production costs, but it is a factor that has a significant impact on taste and brand image. And this extends to customer loyalty, repeat visit rates, and brand reputation.

Now, the era of pushing water to the back when discussing coffee quality has passed. Coffee ultimately begins with water. We must always remember that the touching cup of emotion we want to deliver to our customers also begins with water.