In China, which has a long history of tea culture, various types of tea, such as black tea, green tea, and Pu'er tea, are indispensable drinks in daily life. Many tea lovers will store some favorite teas in their homes, but with the passage of time, whether these teas can still maintain their original flavor and nutritional value has become a matter of concern to everyone. Especially when tea leaves are stored for years, are they still safe to drink? This article will unravel this mystery from the perspective of medicine and tea science.1. Changes in the shelf life and quality of tea1. The shelf life of tea.
The shelf life of tea is affected by a variety of factors, including the variety of tea, processing methods, packaging materials, and storage environment. Generally speaking, the shelf life of green tea is relatively short, because it is not fermented, the contents are active, and it is easily affected by the external environment. Black tea and pu-erh tea have a relatively long shelf life, especially pu-erh tea, and its quality may even improve over time with proper storage.
2. Changes in the quality of tea.
Over time, the chemical composition in tea undergoes a series of changes, such as oxidation, hydrolysis, etc. These changes may result in changes in the color, aroma, taste and nutritional value of the tea. If not stored properly, tea leaves may also be damp, moldy, and deteriorate, producing substances that are harmful to the human body.
2. The drinking safety of aged tea
1. The nutritional value of aged tea.
Although some of the nutrients in aged tea may be reduced due to oxidation and other reasons, they still contain a variety of beneficial components such as tea polyphenols, catechins, caffeine, etc. These ingredients have a variety of biological activities such as antioxidant, anti-inflammatory, antibacterial, etc., and have a positive effect on human health.
2. The safety of aged tea.
For tea leaves that have been stored for many years, if they are stored properly and there is no mold, deterioration, etc., they are generally safe to drink. However, if the tea leaves are damp, moldy, or odorous during storage, they may contain harmful substances such as aflatoxin, posing a threat to human health. Therefore, before drinking aged tea, it is important to carefully check its quality.
3. How to judge whether aged tea is drinkable
1. Observe the appearance of the tea.
Aged tea leaves may become darker or lighter in color, but there should be no mildew or discoloration. At the same time, the cords of the tea should remain tightly knotted and should not be loose or broken.
2. Smell the aroma of tea.
The aroma of aged tea leaves may change, but musty, sour, or other off-flavors should not appear. If the tea leaves emit an unpleasant smell, it may have gone bad.
3. Taste the taste of tea.
Aged tea leaves may become more mellow or softer on the palate, but they should not be bitter, sour, or other undesirable. If the tea doesn't taste good, it could be a sign of deterioration.
4. Check the tea packaging and storage environment.
If the packaging of the tea is broken or the storage environment is humid and unclean, then the quality of the tea may have been compromised. In this case, it should be drunk with caution or avoided.
Fourth, how to store tea correctly
In order to ensure the quality and safety of tea, the correct storage method is crucial. Here are some suggestions:
1. Choose the right packaging materials.
Tea should be packed with packaging materials with good sealing and strong protection from light, such as tin cans, iron boxes, etc. Avoid using packaging materials with poor air permeability, such as cartons and plastic bags.
2. Control the temperature and humidity of the storage environment.
Tea should be stored in a dry, ventilated, dark environment, temperature control below 25, humidity control below 60%. Avoid storing tea leaves in places with moisture, high temperatures, or direct sunlight.
3. Avoid odor pollution.
Tea has strong adsorption and easily absorbs surrounding odors. Therefore, the place where the tea leaves are stored should avoid placing items with odors such as perfume and mothballs.
4. Regularly inspect and turn the tea leaves.
During the storage period, the quality of the tea should be checked regularly, and mildew, odor and other conditions should be dealt with in time. At the same time, the tea can be turned regularly to make it evenly heated and ventilated to maintain stable quality.
In conclusion, tea leaves such as aged black tea, green tea, and pu-erh tea are drinkable if they are properly preserved. However, in order to ensure the quality and safety of tea, we must carefully check its appearance, aroma and taste before drinking, and pay attention to the correct storage method. Only in this way can we fully enjoy the health and deliciousness that tea brings. List of high-quality authors