Ultra fine tea powder is a new type of tea product made from fresh tea leaves through special processing techniques, which can be directly consumed as ultra-fine particles. The particle size is around 300 mesh (diameter 50 μ m).
Ultra fine tea powder was successfully developed by Japan and China in the early 1990s.
At present, ultrafine tea powder has been widely used in industries such as food, beverages, and daily chemical products. At present, ultrafine tea powder mainly includes ultrafine green tea powder and ultrafine black tea powder.
1. Processing principle and technology of ultrafine green tea powder
Ultra fine green tea powder is processed from fresh tea leaves through techniques such as spreading, green protection treatment, withering, rolling, dehydration and drying, and ultra fine grinding.
The key to its processing technology lies in how to improve chlorophyll retention rate and form ultrafine particles. During the processing, special green protection techniques are first applied when fresh leaves are spread, followed by high-temperature withering to destroy the activity of polyphenol oxidase and retain the polyphenol compounds, forming a green tea flavor.
Finally, ultrafine particles are made using ultrafine grinding technology. The quality characteristics of ultrafine green tea powder are: delicate and uniform appearance, bright green color, high aroma, rich and mellow taste, and green soup color.
Ultra fine green tea powder is similar in taste and aroma to regular green tea, but its color is particularly green and the particles are particularly fine.
The quality of ultrafine particles of ultrafine green tea powder is mainly determined by the following three factors:
① Moisture content of semi-finished products: The moisture content of semi-finished products processed with ultrafine green tea powder must be controlled below 5%. The higher the moisture content of semi-finished products, the better the fiber toughness, and the harder it is for fibers and leaf flesh to break under external forces.
② External force application method: The fibers and leaf flesh of semi-finished dried tea plants need to be broken and crushed by external force to form ultrafine particles of ultrafine green tea powder. The diameter of the particles varies depending on the external force applied (crushing method). Both wheel grinding and ball milling methods are used for crushing under the action of rotational force, which is not conducive to the fracture and crushing of tea stems and stems; The straight rod type is based on the principle of hammering, which has the functions of shearing, friction, and tearing. It crushes dry tea plant fibers and leaf flesh thoroughly and has a good effect.
③ The temperature of crushed material tea: green color and fine particles are the main factors affecting the quality of ultrafine green tea powder.
In the process of ultrafine grinding, as the grinding time prolongs, the crushed material tea undergoes intense friction, shearing, and tearing between the materials, which generates heat and causes the temperature of the crushed material tea to continuously rise. Chlorophyll is destroyed under the action of heat, and the color of ultrafine green tea powder turns yellow.
Therefore, during the process of crushing ultrafine green tea powder, the temperature of the crushed material tea must be strictly controlled, and the crushing equipment must be equipped with a cooling device.
2. Processing principle and technology of ultrafine black tea powder
Ultra fine black tea powder is processed from fresh tea leaves through withering, rolling, fermentation, dehydration and drying, and ultra fine grinding.
Its quality features include delicate and uniform particles, brown red color, mellow and sweet taste, rich aroma, and deep red soup color.
Compared with ordinary black tea, ultrafine black tea powder has a very fine particle size (usually around 300 mesh), and its pink color, taste, and aroma are basically the same as ordinary black tea.
Fresh tea leaves in spring, summer, and autumn can all be processed into ultrafine black tea powder, and summer and autumn fresh leaves are the best raw materials.
Processing steps for ultrafine black tea powder: Fresh leaves → Withering (natural withering, withering in a withering trough, or withering under sunlight) → Rolling → Breaking and screening, fermentation → Dehydration and drying → ultrafine crushing → Finished product packaging.
