7542 as a classical and glorious product during lineup of DaYi also has been taken as a benchmark since many years ago till now when I am writing these words in 2018 year.
“75” means recipe used on this tea was created in 1975 year, till 2005 year, it was 30 years old. Any update or evolution on this recipe? We don’t know. Obviously, DaYi leaves questions like this for tea lovers and market. Tea material varies year by year, even the same recipe from the right beginning, it is so difficult to know the detail. But it is not mysterious. We have this tea to try at least by a sample. The next “4” means 4th level tea leaves during the 10 grades of “茶cha菁jing” from the most young bud of highest level of “Royal leaf” to the pure stem of 9th level. “2” means Menghai tea factory during the past 4 big national tea factory in Yunnan province.
Sheng cha which will continuously ferment by complicate chemical reaction of Oxygen, Microbes, Enzyme and other substances contained in tea leaf. And this process is called natural fermentation or evolution which will get better effect under ideal storage condition of humidity around 75% and temperature near 20-25 Celsius with airflow and should be hidden from sun light.
Guangzhou city stored till now. Clean and dry.