What water should I use for the I prepare the perfect cup of tea? Should I use bottled water, tap water, filtered tap water or distilled water? What kind of water tastes best?
Behind water, tea is the most consumed beverage in the world. Factors that affect tea brewing include brewing temperature, water-to-leaf ratio, time, vessel and the composition of the water used.
In this article we will help guide you to the best water for the perfect cup of tea.
How does water impact taste?
First of all water quality varies a lot based on source (spring, surface, ground, aquifers, desalinated), treatment and even the pipes. It can be high/low in minerals (referred to as hard or soft, chlorinated, acidic or alkaline, cold/warm or metallic. Finally the freshness of the water also matters. Newly poured tap water that has been boiled is more oxigenated. Old tap water that has been boiled several times or sitting stale in a carafe may taste very flat as it's dead water.
The type of water has a big impact on taste of water. For example high mineral content combined with chlorine that you find along mosts coasts have a tendency to taste very chemical and bad. Soft water with chlorine on the other hand may taste pure. This naturally also impacts the taste of the tea.
Intuitively you might think that pure water such as distilled, very low mineral content or filtered water with osmosis would taste the best. Pure water should taste the best or the least. But most blind tastes have found the opposite to be true. Most people prefer water with medium to high mineral content.
What type of water tastes best with tea?
A recent study from researchers working out of Cornell University’s Sensory Evaluation Center found that people tend to like green tea tea made with tap water better when it comes to taste. The tap water in this test was medium mineral content (120 TDS) with about 0.5 mg chlorine per liter. According to the research Green tea tasted much less bitter, as well as sweeter, when brewed with tap water than bottled water or reverse osmosis water (in both cases with lower mineral content).
To complicate things the type of tea and water combination also impacted taste. For example black tea brewed with tap water was earthier and bottled water was more flat.
What are the main attributes of tap water that impact taste?
1. Mineral content water for tea
The amount of mineral content, mainly calcium carbonate but also magnesium, sodium, potassium and phosphorus, have a big impact on taste. High mineral content is also what makes the water hard and prone to result in limescale.
Hard water tends to make tea darker and thicker, whereas soft water makes a lighter brisker tea. You cannot only taste but also see the difference. When water hardness is too low (below 20-40 ppm), tea becomes bitter and astringent, and color may be reduced.
Distilled water therefore makes an awful cup of tea (see below). Although it's pH may be good, it is the opposite of a hard water, completely lacking in minerals and making a very bland brew. When considering mineral content, you want a water that contains the right combination of minerals, but is not too hard. Our blind tests indicated that about 60-120 mg/L of minerals (mostly calcium and magnesium) provided the best taste.
In terms of TDS (measuring the total amount of minerals) the ideal range seems to be 100-300 but people rate the tast as good with up to 600.
2. pH - Acidic or Alkaline water for tea?
A water's pH level also has an impact on the flavour it imparts to your tea. Pure water is completely neutral, with a pH of 7, whereas acidic lemon juice is 2, and alkaline bleach is about 11. The pH of your tap water ranges from 6.5 to 9.5, with harder, more mineral water tending to be higher in pH.
Ideally, your tea brewing water should be neutral, with a pH as close to 7 as possible. Alkaline, minerally water tends to make tea taste either dull, or obscures the delicate flavours of the tea leaves.
On the other hand Alkaline water increases the antioxidant power of tea.
3. The freshness of the water impacts taste
For the best, liveliest cup of tea you’ll need freshly drawn water. That means don’t just flip the switch on your kettle and reheat water that’s been sitting there already - start again by filling your kettle with fresh water. The reason for this is that the best flavour is drawn out of the tea leaves using oxygen-rich water.
4. Other tap water attributes for tea
Sulphur, chlorine, and too much sodium are also to be avoided, as they can ruin a good cup of tea by making it either too eggy or salty. Minerals like magnesium and calcium on the other hand, can add flavour to your cup. So where do you obtain this oxidized, neutral water with just the right amount of minerals?
Is bottled, tap or filtered tap the best for tea?
There are many options when it comes to drinking water, and in the end it comes down to personal preference. Still, there are advantages and disadvantages inherent to each choice.
The water that comes out of your tap may or may not be good for tea. The biggest issue is normally chlorine followed by limescale and metals. Request a water report from your local water provider or if you live in spain then check out our water quality database.
This is also a mixed bag. Most bottled water will have some minerals but I the content varies a lot. Make sure you buy a brand with 40-120 mg calcium and other minerals per liter) and that it’s as pH neutral as possible. Also, you might notice a plastic taste to your tea if your bottled water came from a plastic bottle.
From a health perspective mineral water is a big marketing lie. There is significant evidence that bottled water is not healthy. Several studies have found microplastics, phthalates and hormones in bottled water.
Finally bottled water should be avoided from an environmental point of view. Even if you recycle the plastic pollution and CO2 footprint cannot be justified when there are much better alternatives.
This is, in our opinion, the best option unless you already have great tasting tap water. A high quality water filter is a great way to eliminate the bad-tasting stuff (chlorine , most microbes and sediments). They may also remove volatile organic compounds, the giardia parasite and anything that might diminish good flavors. Another nice thing about filters is that they do not impart a plastic taste to water like bottled water can.
Most Activated Carbon Filters do not remove much else, though, so using filtered water can lead to scale buildup in your kettle and teaware. Therefore look for a multi-stage filter that is independently tested for the substances you need to remove.
If your water is very hard then you might need to consider ion exchange or RO water filter. But be aware that this more often than not makes for a flat tasting cup of tea, in the same way that distilled or ‘pure’ water would - it simply doesn’t have enough mineral content.
Distilled water would, at first, seem to be the best choice. It has virtually no dissolved minerals, so it will not leave mineral deposits in your teaware, and it is the most pure source of water for the average tea drinker. However, distilled water is very flat-tasting, and will leave your tea tasting dull and boring.
Don’t use hot tap water
When interviewing people about the water they use for tea some people told us they used hot tap water in the kettle to heat it faster. Don’t. Sure, it will take a little longer to heat up, but the process of heating your water makes it borderline unpotable. It's ok for washing dishes, but I wouldn't suggest consuming water that was drawn hot from the tap. The reason is simply that your boiler is often full of bacteria and may also suffer from corrosion.
The water from your childhood tastes best
Tap water is an acquired taste. Therefore many of our blind tests showed that the best water for tea is the water you grew up with. It makes sense as tap water is something that we generally like because it doesn’t taste anything and we get used to this. When taste changes our taste buds say hmmm… what is this?
I did everything you told me and the tea still tastes bitter?
If your tea is tasting bitter, don’t be too quick to blame the water. The problem may be the use of inferior tea leaves or steeping too hot or for too long.
Target Temperature & Brew Times for Tea:
- White tea: 76°C, 1–2 min steep
- Green tea: 76–82°C, 1–3 min steep
- Black tea: 97–100°C, 3–5 min steep
Conclusion on the best water for tea
Here's the summary on water for brewing the perfect cup of tea.
- Use tap or filtered tap water if you can. Avoid bottled water as it’s often worse for taste, not better for your health and bad for the planet.
- The water quality attributes should be within this range:
- Hardness: 40-120 ppm is ideal (4-8 dH). Hard water can flatten taste.
- Total Dissolved Solids (TDS): 100–300 ppm
- PH: Neutral (between 6–8) (Note: Your brewed tea will be slightly more acidic, with a pH of 4.5–6)
- Chlorine: As close to 0 as possible
- A high quality water filter such as EcoPro or EcoPro Compact will vastly improve taste by removing chlorine and other substances as well as reducing limescale
Also read our blog about best water to brew the perfect coffeee