FoodHow to keep your tea film-free: Tips for better brewing

How to keep your tea film-free: Tips for better brewing

You leave a cup of tea for a few minutes, come back, and see an unsightly film? This scenario occurs not only to you. It's a natural reaction resulting from the properties of tea, so there's no need to worry. The film is not harmful, but if you want to avoid it, you can try three practical tips.

The cause of the unsightly deposit on tea might be hard water.
The cause of the unsightly deposit on tea might be hard water.
Images source: © Adobe Stock
Anna Galuhn

Leaving tea in a cup for a few minutes after brewing can lead to an unattractive film. The source of this phenomenon is a chemical reaction between oxalates present in tea and calcium from the water, which leads to the characteristic film on the surface of the hot drink. This phenomenon, although visually unappealing, is not harmful to health.

Film on tea due to the presence of polyphenols

Some researchers suggest that this film may be the result of the presence of polyphenols in tea leaves. There are theories that the more polyphenols, the greater the risk of film formation. However, paradoxically, the amount of polyphenols indicates the high quality of tea because these are antioxidant compounds beneficial to health.

Green and white tea, which are minimally processed, contain the most polyphenols. There are slightly fewer in black tea, as these are lost in the leaf oxidation process. A large number of polyphenols is found in Chinese fermented pu-erh tea, which can also assist in weight loss.

How to avoid film on tea?

You can prevent an unwanted film by filtering the water before boiling it. The presence of a large amount of calcium, found in hard water, is responsible for the film. In this case, filtering is an effective solution. You can also use spring water for brewing tea, which further reduces the chances of film formation.

Hard water not only affects the appearance of tea but also its taste. Therefore, it is worth considering changing your habits. Spring or filtered water will make the drink more delicate and its aroma much fuller.

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