Effects of hot and cold steeping methods on antioxidant activity in tea

Antioxidants are molecules that protect your cells from damage, and tea is bursting full of them, but have you ever wondered whether steeping your tea in hot or cold water affects its antioxidant levels? Is the difference even significant enough to worry about? Researchers at Università Politecnica delle Marche tested the effects of steeping temperature on antioxidant levels in black, green, white, and oolong tea.

Black Tea                     Green Tea                       White Tea                    Oolong Tea

All images from Wikipedia Commons

The results showed that antioxidant activity is generally higher in tea brewed with hot water, but using statistics, this difference was found to be significant only for green tea. White tea deviates from this trend, showing statistically higher levels of antioxidants when brewed with cold water.

Two different analyses were conducted to measure the antioxidant ability of the four teas. Each analysis independently yielded similar results.

Fig 1: Antioxidant level measured in units of (mM GAE), showing statistically higher antioxidant levels for white tea brewed with cold water and for green tea brewed with hot water. Black and Oolong tea brewed with hot water showed higher antioxidant levels, but was not statistically significant.

Venditti E, Bacchetti T, Tiano L, Carloni P, Greci L, Damiani E. Hot vs. cold water steeping of different teas: do they affect antioxidant activity?. Food Chemistry. 2010 Apr 15;119(4):1597-604.

The researcher’s findings suggest that different types of teas contain different types of antioxidants, which are sensitive to different steeping temperatures. The effect of steeping temperature on tea depends on which antioxidants are present. For example, white tea brewed using cold water yielded higher antioxidant levels because some antioxidants may be degraded at higher temperatures. Brewing at lower temperatures preserved those heat sensitive antioxidants. Another example is brewing green tea, where tea brewed with hot water yielded higher antioxidant levels because some antioxidants may be extracted from the leaves efficiently only at higher temperatures.

Whether you prefer black, green, white, or oolong tea, and whether you prefer hot or cold brewing methods, all of these types of teas contain many antioxidants and are a healthy drink choice. Therefore, it is more important to drink the type of tea you like best, brewing it with the method that you prefer, which will ensure that you continue to consume this healthy drink!

-Gareth Lee