Tea Brewing Guide: Water Requirements - How to Make Your Tea Taste Better

Water is the foundation of tea, carrying its essence. The quality of water directly affects the aroma, color, and quality of the tea infusion. 90 percent of the tea's quality is determined by the water used. Even the finest tea can taste extremely different and lack its intended quality if brewed with unsuitable water. Therefore, choosing the “right” water to brew tea is fundamental and often overlooked.

If You Live in a Rural Area

Different regions and sources of water have varying compositions influenced by soil, geography, and climate. As early as the first Chinese tea book, "The Classic of Tea" (茶經，760-780 AD), Lu Yu identified the key factors:

“Mountain spring water is the best, followed by river water, and well water is the least favorable.”

Explained in modern language,

1. Good water quality possesses the following characteristics: clarity, lightness, sweetness, coldness, and liveliness.
2. Mountain water from fast-flowing streams should not be used. From a modern scientific perspective, such water is hard and turbid.
3. Stagnant water is not good; only flowing water is fresh and lively. The difference in oxygen content affects the tea's development.

If you're fortunate enough to have access to natural mountain spring water for brewing tea, you have a great blessing as a tea drinker. The key is to ensure the upstream water source is unpolluted; drinking healthy water is paramount.

If You Live in the City

If you live in a city consider two main factors when choosing suitable water: The mineral content (soft or hard water) and the pH level.

Soft Water vs. Hard Water

What is soft water? What is hard water? Generally, water hardness is measured by TDS (Total Dissolved Solids), presented in mg/L or ppm (parts per million). The difference between hard and soft water lies in the mineral content, such as calcium, magnesium, and iron. Even though there is no strict definition, water with calcium and magnesium content below 60 mg/L is considered soft and above 120 mg/L hard. Soft water with fewer minerals is clear and pure, highlighting the tea's intrinsic flavors, making the tea smooth and palatable. It also better releases the aromatic compounds in tea, enhancing its fragrance and delicate layers. In contrast, hard water has a firm taste, and minerals easily combine with tea alkaloids and other flavor substances, forming insoluble precipitates, making the tea taste bitter and harsh. When boiled, calcium and magnesium ions crystallize, producing significant scale, directly ruining the tea's aroma, taste, and sweetness.

Water Sources in the City

Tap Water

Tap water is treated and disinfected by water companies. Most tap water is hard, and during transportation it can accumulate even more iron. In older piping areas, this may give the tea a brown appearance. Disinfectants like fluorides can react with tea compounds, making the tea taste bitter.

I personally do not recommend using tap water for brewing tea. However, if you still wish to use it, here are some methods to improve its quality:

A. Purification: Remove suspended impurities to make the water clear. Reverse osmosis is common, but over-filtering minerals can result in high fragrance but an empty body with no layers. Balance is key!

B. Softening: Boil the water longer or use distillation to remove impurities.

C. Let the water sit overnight: This allows the fluoride to dissipate, reducing unpleasant odors and making the tea cleaner.

Mineral Water

Different countries have slightly different definitions of mineral water, broadly classified as mountain spring water or deep underground water with natural minerals. They are commonly rich in trace minerals beneficial to health.

Some mineral waters taste great but may not be suitable for brewing tea. When choosing a brand at the store, check the calcium and magnesium concentrations on the label, ideally on the very low end (single digit values if able to find).

Mineral Content and Tea Taste

• High sodium: Makes the tea taste salty.
• High calcium and magnesium: Oxidize lutein in tea, darkening the tea color, causing turbidity, and losing freshness.
• High iron: Reaction with polyphenols, creating dark complexes, dulling the tea color (critical > 5mg/L).
• High aluminum: Lightens tea color and dulls the taste.

Water should not be overly hard or soft; personal experimentation is necessary to find the best-suited brand for your region.

pH Level

The water’s mineral content affects the solubility of tea components. However, just referencing TDS is insufficient for understanding water quality. The pH level is also crucial for the tea's flavor stability.
The biggest impact is on tea color. When pH exceeds 5, tea color deepens. At 7, lutein tends to oxidize, altering the color and taste. Mineral water pH generally ranges between 7.0-8.0, slightly alkaline. For brewing tea, a pH of 6.7-7.3 is recommended, as it best showcases the tea's true color, aroma, flavor, and charm.

Summary

To summarize the effects and principles of water on tea, consider these points:
1. The best water for brewing tea is natural, unpolluted mountain spring water, followed by river and well water.
2. Soft water is better than hard water.
3. Mineral water is better than tap water.
4. When choosing a mineral water brand at the store, pay particular attention to the calcium and magnesium concentrations on the label, aim for the lowest concentrations.
5. The recommended pH for brewing tea is 6.7-7.3, slightly alkaline.

I hope that by improving the quality of water, tea enthusiasts can enjoy more delicious tea and enhance their special tea-drinking experience.