How Water Quality and Temperature Affects Premium Tea

When a customer orders any kind of tea, including the most premium tea, what they’re actually getting is just 2% tea compounds. The other 98%? Water.

Yes, that’s right: water is the biggest ingredient in a cup of tea. And that means it can have a dramatic impact on flavour, aroma, mouthfeel, and more.

Café owners, hoteliers, restaurateurs, and anyone else who serves and sells premium tea should pay attention to both water temperature and quality. Doing so will improve the quality of their offerings, resulting in more satisfied customers. And, as an added bonus, their equipment will probably last longer.

So, let’s break down what all tea brewers and vendors should know about water.

Why Brew Temperature Matters

All teas are different, and so too are the temperatures at which they should be brewed. Alice Evans is Head of Tea at Canton Tea in the UK, and she tells us, “Each tea has its own unique makeup of chemical compounds: polyphenols, carbohydrates, pigments, amino acids, volatiles, etc.”

Take the tannins in tea: when the water is too hot, it can dissolve these. The result is an astringent, bitter, and unbalanced drink. Green tea is rich in tannins and so brewers should be careful to avoid brew temperatures that are too high, Alice cautions. On the other hand, water that’s too cool will brew a tea lacking in flavour, aroma, colour, and body.

How to Ensure The Right Brew Temperature Is Used

The best water temperature will vary according to the specific tea being brewed, Alice emphasises, but should fall somewhere within these ranges:

• Black and Pu’er: 90–95ºC
• Oolong and white: 80–95ºC
• Green: 60–80ºC

For an ideal infusion, she recommends asking the tea supplier for an exact temperature. At the same time, brewers can experiment with temperatures to create their own recipes, which may be more suited to their customers’ palates.

For true precision brewing, a temperature-controlled water source such as the Marco MIX is crucial. “I have found the MIX to be the best option available,” Alice tells us, explaining that it makes it easy to switch between temperatures and so increase efficiency.

Additionally, she advises carefully selecting the brewing vessel. A good pot should hold the brew’s temperature while also allowing the leaves enough space to move around.

Using the Marco MIX 1 Button Font to brew tea in a glass pot.

Water Quality: What Are The Best Brewing Parameters?

Water varies from place to place, and so does its quality. And whether it’s white tea or a delicate First Flush Darjeeling or Japanese Green Tea , the water hardness, pH, and chlorine level can all influence the taste of the final beverage, enhancing or overwhelming the leaves’ flavours and aromas.

Alice tells us, “In my experience, I have found that tea prefers softer water, with a pH between 7 and 6.5.”

Let’s break these different factors down.

Hardness & Total Dissolved Solids

We often talk about “hard” and “soft” water, but what does this actually mean? Well, we’re actually better off starting with a different piece of jargon: total dissolved solids (TDS). TDS refers to any minerals, salts, metals, or other solids that have been dissolved in the water – and, of course, all these will impact on the taste. For many professionals, 50–150 ppm TDS is an acceptable range.

Water hardness is the result of particular dissolved solids in the water: calcium, magnesium, iron, and manganese, along with some others in smaller amounts. In other words, it’s a subsection of TDS.

The presence of these four solids is not a bad thing; it’s only a problem if there are too many, or too few, of them. Ideally, cafés, hotels, and restaurants would have a water hardness of one to four grains per gallon (or a filtration and softening system capable of achieving this).

Calcium and magnesium are the primary minerals responsible for water hardness. Up to a certain amount, they can enhance the extraction of flavour compounds. However, if there are too many calcium or magnesium molecules in the water, they will crowd out the flavour compounds and prevent extraction.

Iron and manganese, which are found in smaller quantities, can affect water’s flavour and colour. In general, too many minerals will also create a more metallic taste – while too few will leave the tea tasting dull.

What’s more, the water quality can have an impact on the water boiler and font. Calcium bonds particularly well and so can lead to limescale build-up.

pH levels

A quick science class recap: the pH scale ranges from 1 to 14 and indicates whether the water is alkaline or acidic. 7 is neutral, while anything less is acidic and anything greater is alkaline.

In premium tea, the more neutral the water, the better. In particular, highly alkaline water can be bitter and contribute to limescale build-up (hard and alkaline water is a nightmare combination).

Chlorine

Chlorine, along with other chemicals, is often used to treat water. However, it can also affect the flavour and aroma of a cup of premium tea. We’re talking an unpleasant salty taste or even a delicate yet disturbing whiff of something bleach-like.

Unlike water hardness, when it comes to chlorine, there’s no such thing as “good in moderation” – the ideal chlorine content is 0.

How to Improve Water Quality When Brewing Tea

The first thing any tea brewer or seller should do is understand their water. Test strips can give a quick DIY insight into water quality; most water suppliers will also be able to provide information.

Unfiltered tap water is rarely ideal for brewing water. However, bottled water is pricey and distilled water lacks those important calcium and magnesium molecules. It’s best to filter tap water to get the ideal quality.

The multi-temperature Marco MIX, for example, comes with a built-in filtration system, taking care of water temperature, quality, and efficiency at the same time. Alternatively, the filters (which are the Marco Bestmax Filters) can be purchased separately. In addition to filtering out excessive or unwanted chemicals, they have a limescale protection system that will improve the longevity of the water boilers and/or hot water distribution system.

No café owner, hotelier, or restaurateur should overlook the importance of water quality and temperature for premium tea. It can ensure better-tasting and more aromatic beverages, longer-lasting equipment, and, of course, greater customer satisfaction – all essential things for any business.

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