Is it really good to make tea in a thermos cup? Winter drinks should be so foamy?
Answer: In winter, many people like to make tea in a thermos cup, so that they can have a sip of hot tea at any time, but is it really good to make tea in a thermos cup?
CCTV “Life Tips” conducted related experiments through the School of Tea and Food Science and Technology of Anhui Agricultural University. The experimenters selected two servings of green tea of the same amount, put them into a thermos cup and a glass cup respectively, and brewed them for 5 minutes, 30 minutes, 1 hour, and 2 hours. , 2 portions of tea soup after 3h were analyzed.
The above is the tea soup in the thermos cup, and the bottom is the tea soup in the glass cup
Experiments have found that after the tea leaves are soaked at high temperature for a long time in a thermos cup, the quality will decline significantly, the soup will turn yellow, the aroma will be ripe and boring, and the degree of bitterness will also increase significantly. The active substances in tea soup, such as vitamin C and flavonols, are also reduced. Not only green tea, but also other teas are not recommended to be brewed in a thermos cup.
In addition to tea, high-protein drinks such as soy milk, milk, and milk powder, it is not recommended to use stainless steel thermos cups for long-term storage.
The experiment found that after putting hot milk powder and hot milk into the thermos cup for 7 hours, the number of bacteria changed significantly, and it increased significantly after 12 hours. This is because soy milk, milk, etc. are rich in nutrients, and when stored at a suitable temperature for a long time, microorganisms will multiply, and it is easy to cause abdominal pain, diarrhea and other gastrointestinal symptoms after drinking.
Pay attention to purchase
When purchasing stainless steel thermos cups, you may notice that some products say 304, 316, 316L stainless steel. What does this mean?
Two types of thermos cup product information on a certain platform
First of all, let’s talk about the working principle of the thermos cup. The stainless steel thermos cup has a double-layer structure. The inner tank and the two layers of stainless steel on the cup body are welded and combined to form a vacuum. The heat in the cup is not easily transmitted out of the container, achieving a certain heat preservation effect.
During use, the stainless steel liner of the thermos cup directly contacts liquids such as cold and hot water, beverages, etc., and the frequency of soaking alkaline tea, water, carbonated beverages, and high-temperature liquids for a long time is relatively high. These liquids are easy to corrode the inner tank and its welded parts, thereby affecting the service life and hygienic performance of the product. Therefore, stainless steel materials with strong corrosion resistance should be selected.
304 steel is one of the most common stainless steel, known as food-grade stainless steel, normal contact with water, tea, coffee, milk, oil, salt, sauce, vinegar, etc. is no problem.
316 steel is further upgraded on this basis (controlling the proportion of impurities, adding molybdenum), and has stronger corrosion resistance. In addition to oil, salt, sauce, vinegar and tea, it can resist various strong acids and alkalis. 316 stainless steel is mainly used in the food industry, watch accessories, pharmaceutical industry and surgical equipment, the production cost is higher and the price is higher.
316L steel is a low-carbon series of 316 steel. In addition to having the same characteristics as 316 steel, it has excellent resistance to intergranular corrosion.
When choosing a product, you can make a comprehensive judgment based on your needs and cost performance, and choose the right product.
Post time: Feb-17-2023