As the weather gets hotter, many people do not want to drink hot tea. The weather was hot and the sun was like fire, and after drinking a cup of steaming tea, I immediately sweated like rain.
Therefore, many tea lovers like cold brewing tea in summer. Cold brewing tea can relieve heat, and is healthier than other beverages, and the taste is very sweet.
Among them, Baihao Silver Needle is particularly suitable for cold soaking.
However, some tea friends also have doubts: the cold brewing tea water temperature is very low, and the Baihao Yinzhen is not twisted. Under this low temperature, can the contents of the Baihao Yinzhen be fully released?
Researchers from Fujian Agriculture and Forestry University China White Tea Research Institute and Agricultural Products Quality Research Institute have conducted a special set of experiments on the effect of low-temperature cold soaking on the release of Baihao Silver Needle. They used 4℃, normal temperature, 50℃, 80℃, The water temperature of 100℃ was brewed for 1 to 15 hours, and the amount of the main flavor substances was detected by comparing different water temperatures and brewing time.
The results showed that as time passed, the leaching amount of tea polyphenols, amino acids and caffeine increased overall, while the leaching rate decreased.
Among them, tea polyphenols have the highest leaching rate after being brewed in boiling water for 1 hour. When cold brewing with 4°C water temperature, the tea polyphenols are leached slowly in the early stage, but when the brewing time reaches 15 hours, the amount of tea polyphenols leaching is 8.36 times that of 1 hour.
In addition, after 15 hours of brewing at 4°C and room temperature, the leaching amount of tea polyphenols reached 18.72% and 21.41%, respectively, which exceeded the leaching amount of tea polyphenols of 1 hour brewing at 100°C.
It can be seen that when Baihao Yinzhen is brewed for a long time at low temperature, the amount of tea polyphenols leached can reach or exceed the amount of tea polyphenols brewed for a short time at high temperature.
In terms of free amino acids, the total amount and rate of extraction are basically consistent with the release law of tea polyphenols.
In addition, the amount of free amino acids leached for 15 hours at 4°C is 7.55 times that of 1 hour of brewing, reaching 2.19mg, and the amount of free amino acids leaching is higher than that of boiling water for 1 hour (1.81mg).
For caffeine, after 15 hours of brewing at 4°C, the leaching content% is 1.5534, which is 4.03 times that of 1 hour, which is close to the leaching content of caffeine brewed in boiling water.
In general, when brewing for a long time at low temperature, the leaching rate is gradually higher than that for long time brewing.
In addition, when Baihao Yinzhen was brewed with water at 4°C for 15 hours, the leaching amount of the three main contents all reached or exceeded the content of high-temperature short-term brewing.
The above experiments show that there is no problem in brewing Baihao Yinzhen at low temperature for a long time, and its content and main health functions can fully meet our needs for drinking tea.
Therefore, in the hot summer, quickly soak a cup of Baihao Silver Needle and put it in the refrigerator, and feel its coolness and freshness the next day.