Instant black tea processing method

Abstract

The invention discloses an instant black tea processing method. The method includes: adding water into tea leaves, and extracting; concentrating liquid obtained by solid-liquid separation; allowing concentrated liquor to pass through an electrodialysis concentration chamber to absorb alkali for increase a pH value; adding an appropriate amount of alkali to increase the pH value to a required value; standing for oxidization; after oxidation reaction is finished, removing excessive alkali through an electrodialysis desalination chamber to decrease the pH value of tea water to a required value; sterilizing and drying to obtain instant black tea. By means of electrodialysis, the alkali is absorbed from a last batch of tea water, then the appropriate amount of alkali is added to increase the pH value to the required value, and after oxidization is finished, the excessive alkali is removed by electrodialysis and supplied to a next batch of tea water to decrease the pH value to the required value, so that alkali recycling in the whole production process is realized, alkali consumption is substantially reduced, acid addition for neutralization of the excessive alkali is avoided, and production cost can be greatly reduced. In addition, due to reduction of added non-tea substances, the instant black tea is high in purity and excellent in quality.

Description

technical field [0001] The invention relates to a processing method of instant black tea, which belongs to the technical field of tea processing. Background technique [0002] Instant tea is generally made by extracting tea leaves with water, filtered or centrifuged, concentrated and dried. It is a solid powder that can quickly dissolve in water, has no tea residue and maintains the unique flavor of tea. It is generally processed by conventional processing methods. What kind of tea is it generally? What kind of instant tea is processed from raw materials, the clarity of the product is relatively poor after being dissolved in water. [0003] Chinese patent ZL01118460.4 discloses a cold-water-soluble acid-resistant instant black tea powder and its manufacturing method. Black tea leaves are soaked at 80-90°C, and the obtained tea extract is immediately cooled to room temperature, and then coarsely filtered and finely filtered. Finally, use membrane concentration or evaporation...

AI Technical Summary

Problems solved by technology

It can be seen that in the prior art, in order to convert green tea and oolong tea into instant black tea and improve the clarity and acid resistance of instant black tea, there is a method for oxidation by adjusting the pH value of tea water, but usually first adding alkali to improve the pH of tea water After the reaction is completed, acid is added to neutralize excess alkali to reduce the pH of tea water, resulting in the addition of more acid and alkali auxiliary materials, high production costs, and the final reduction in the purity of instant tea products, which affects the quality

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