Tee fermentiert

fermented tea

fermented tea

  • What is fermented tea?
  • Fermented tea stays alive longer
  • Is fermented tea healthier?
  • This prepares the fermentation of the tea
  • This is how purple tea is fermented
  • Tea fermented in numbers

What is fermented tea?

Tea is diverse. What most people don't realize is that green tea, black tea, white tea, oolong tea, and yellow tea can all be obtained from a tea plant, or even better, a tea leaf.

Suppose we pick a tea leaf from a plantation with an absolutely identical character. From this sheet it would then be possible to develop the varieties mentioned above, depending on the processing.

Only purple tea is a mold and represents an exception. A purple spiced tea leaf can therefore never be processed into green or black tea etc. The type of tea and the enjoyment of the tea thus depends on the various production methods.

Fermented tea stays alive longer

Tea that has been fermented generally has a longer shelf life/enjoyability. He keeps "his soul" over a longer period of time. Without fermentation, the tea often does not remain tasty for longer than 14 months. Fermented tea stays alive longer and has a unique taste.


Is fermented tea healthier?

In the case of fermented purple tea, it can be seen that the fermentation contributes more to preservation than to conscious health promotion. Nevertheless, the molecular chains change and with it the effect of non-fermented purple tea to fermented purple tea.

More tannins develop. These are called tannins and occur as polyphenols. These are secondary plant substances that also determine the color of agricultural products and also fulfill an important function with regard to health purposes. However, the context must be taken into account as to whether it can also be used as a medicinal product.

  • Fermented tea has a high tannin content
  • Tannins provide structure and have an antioxidant effect
  • Tannins belong to the secondary plant substances .
  • They are also called tannins
  • Purple tea ferments, partially converting catechins into higher molecular weight compounds such as theaflavins or thearubigins


They have anti-inflammatory, antihypertensive, cholesterol-lowering and astringent effects. Good for stomach ache.


Tannins hinder the absorption of iron, calcium, magnesium, phosphorus and some medicinal substances. Not seriously, of course, but only if you are being treated for this. Certain proteins in the intestine, which are responsible for the water and mineral balance of the intestinal cells, no longer react after consuming tannin.


This prepares the fermentation of the tea

Fermented tea is obtained through an oxidation process. At our Red Hill organic farm in Kenya we have to consider several processes to obtain a good fermented tea .

During the harvest on our tea plantation, the purple tea we grow must be processed no later than three hours after picking the tea leaf. Longer waiting times affect the quality. If you want to know what purple tea is, you can get more information via this link .

After being picked, the tea leaves are first dehumidified and then rolled. When we harvest and process the tea on our farm, we first wither the tea in a dry room for 14 to 18 hours. This is the first step in removing the moisture from the purple tea leaf.

After this process we start rolling. The rolling doesn't have an aesthetic purpose, even though tea leaves look nicer that way. The rolling of the tea leaves causes the tea cells to rupture and the essential oils to ooze out of the cells.

This is how tea is fermented

Not only does the development of the essential oils begin with the rolling, but the fermentation of the tea already begins.

Fermentation is an oxidation and fermentation process of the cell juice that escapes during rolling. The fermentation requires tact and attention. In the process, with the help of atmospheric oxygen, tannins are converted into thearubingen and theaflavin. Only a quarter of the tannins present in the purple tea leaf remain.

The fermentation process on our RedHill organic farm, which we carry out in a small adjoining room away from the main building, takes about 3 hours. The oxidation is subjected to constant testing. Experience plays a big part here, as the smell of the leaf gives the greatest clue. When we believe that the fermentation of the tea has reached its peak, the drying of the tea begins.

This practically freezes the state of the tea in terms of taste and oxidation. Attached is an overview of the components of the tea before and after fermentation.


Constituents of tea before and after fermentation

Specification in percent Water tannin Free caffeine Caffeine bound to tannin total caffeine
Immediately after picking 73.26 29.70 0.58 3.66 4.24
After two hours of fermentation 35.57 17.26 2.72 1.39 4:11
After roasting 9.67 12.59 3.20 1.07 4.27

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