The same drink from the same kettle can do both good and harm, depending on how long it has been infused. If you have brewed flavored tea, do not deny yourself the pleasure of drinking it hot. Moreover, cold tea is not very healthy.
“Old brew can be downright dangerous. For example, history tells us that in Japan yesterday’s tea was equated with a poisonous substance,” said Elena Truskova, a physician and nutritionist, reports Dr. Peter.
According to her, over time, the harmful alkaloid guanine accumulates in the brew. It is not even guanine itself that is harmful, but the substance into which it is converted over time (gaunidine). Due to the accumulation and negative changes in its properties, guanidine adversely affects the nervous system.
At what temperature to brew tea
Studies have shown that the time and temperature of brewing tea are extremely important for the properties of the drink we end up with. It is these conditions that decide whether the resulting drink will be beneficial or harmful.
“It turned out that tea brewed with 95° water and infused for 10 minutes is ideal. After 30 minutes, the spatial formula of tea catechins changes, which affects its properties. As a result, the same drink, from the same kettle, can do both good and harm, depending on how long it was infused,” Truskova explained.
Why tea is good for you
Both green and black tea are rich sources of antioxidants. In green tea, most of the beneficial properties are due to catechins, and in black tea – theaflavins and thearubigins. It is the ratio of their concentration that determines the quality of black tea. In fresh tea, their ratio should be >0.1.
Tea can inhibit the development of cancer, increase energy, improve bile flow, and much more. All of the beneficial properties of tea apply only to freshly brewed tea, the nutritionist warned.