Why Water Hardness Matters for Coffee and Beverage Businesses

When running a café or beverage business, attention is usually placed on coffee beans, tea leaves, milk, syrups and recipes. However, one major ingredient is sometimes overlooked: water.

Research published by the School of Food Science & Biotechnology at Kyungpook National University notes that water makes up more than 98% of coffee. The researchers prepared coffee using waters with different hardness levels and found differences in the concentrations of several extracted coffee compounds.

Water hardness is mainly associated with dissolved calcium and magnesium. These minerals are naturally present in many water supplies, and their concentration varies depending on the water source and local geology.

For an F&B business, hardness matters for two reasons. First, mineral composition can influence coffee extraction. Research from the University of Bath showed that calcium and magnesium interact with organic compounds found in coffee and can affect how those compounds are extracted during brewing.

Second, hard water can contribute to limescale when it is heated. This can become important for cafés and restaurants using espresso machines, boilers and other equipment that repeatedly heats water throughout the day.

This means simply aiming for the lowest possible TDS or removing every mineral is not necessarily the correct approach for every F&B operation. The composition of the water matters, and different beverages and equipment may have different requirements.

For cafés especially, water should be considered both an ingredient and part of equipment management. Understanding hardness and other relevant water characteristics can help businesses make more informed decisions about their water treatment. This content was AI-generated, please review yourself.

References

1. Yoo, I.K., Jang, D.H., Kwon, W.J., Lee, K.H. & Lim, J. (2020). Effect of Water Hardness on Coffee Composition and Coffee Preference by University Students. Korean Journal of Food Science and Technology, 52(5), 435–440. Kyungpook National University.
https://research.knu.ac.kr/en/publications/effect-of-water-hardness-on-coffee-composition-and-coffee-prefere/

2. Hendon, C.H., Colonna-Dashwood, L. & Colonna-Dashwood, M. (2014). The Role of Dissolved Cations in Coffee Extraction. Journal of Agricultural and Food Chemistry, 62(21), 4947–4950.
https://pubmed.ncbi.nlm.nih.gov/24802110/

3. Drinking Water Inspectorate (UK). Water Hardness / Hard Water.
https://www.dwi.gov.uk/consumers/learn-more-about-your-water/water-hardness-hard-water/