The correct way to make tea in a stainless steel thermos cup
When it comes to brewing tea, everyone has their own preferences. Some prefer clear glass cups, watching the tea leaves unfurl and tumble in the water, their myriad forms. Others favor the rustic, elegant purple clay teapot, believing the clay absorbs odors and enriches the tea’s aroma. Many also prefer stainless steel thermoses, which are lightweight and durable, allowing them to enjoy warm tea at any time, whether commuting or enjoying the outdoors. However, recent rumors that brewing tea in stainless steel thermoses releases heavy metals and is harmful to the body have caused many to wonder.
In fact, this claim shouldn’t be taken seriously. First, it’s important to understand that tea is indeed slightly acidic, thanks to tea polyphenols and other substances found in tea leaves. However, the strength of this acidity is very limited. my country has strict safety testing standards for stainless steel utensils: when stainless steel products are placed in a 4% acetic acid solution, boiled for 30 minutes, and then soaked for 24 hours, the chromium migration must not exceed 0.4 mg/dm². What does 4% acetic acid mean? It’s roughly twice the acidity of white vinegar, while tea has less than one-tenth of that, making it minimally corrosive to stainless steel.
Brewing tea in a stainless steel thermos is certainly convenient and quick, but there are significant considerations to making the best tea! Today, we’ll detail the key points of using a stainless steel thermos, allowing you to enjoy the authentic aroma of tea even in your fast-paced life.
Chinese tea culture is extensive and profound, and traditional tea brewing emphasizes the utensils, water temperature, and time. When using a stainless steel thermos, remember: while its excellent sealing properties aid in tea fermentation, it’s crucial not to soak for extended periods!
Tea is rich in nutrients, including proteins, vitamins, minerals, and active substances like tea polyphenols. During the brewing process, these ingredients are gradually released, giving the tea its unique flavor. However, if tea leaves are continuously steeped in high temperatures, excessive precipitation of substances like tea polyphenols and tannins can occur, affecting not only the taste but also the nutritional value.
It’s particularly important to note that the high temperature environment of a stainless steel thermos can cause three major problems: first, it destroys heat-sensitive components in tea leaves, such as vitamins; second, it accelerates the volatilization of aromatic compounds, significantly reducing the tea’s aroma; and third, it can lead to over-fermentation, which can strain the digestive and cardiovascular systems if consumed for extended periods.
Therefore, when brewing tea in a stainless steel thermos, there are three key points to keep in mind: controlling the water temperature (80-90°C is recommended), managing the brewing time (no more than one hour), and choosing the right type of tea (highly fermented black and dark teas are recommended). Also, ensure that the tea is consumed promptly to avoid leaving it sitting for long periods.
Of course, there are also minor details to keep in mind when using a thermos. Wash the cup promptly after drinking to prevent tea stains from clinging to the cup’s walls and forming a stain. These residual stains not only affect the appearance but, over time, can breed bacteria and compromise drinking water hygiene. Wiping with a soft cloth dipped in baking soda will easily remove tea stains and keep the cup clean.
In addition, when choosing a thermos, be sure to look for reputable brands and check for the “food contact stainless steel” label to ensure compliance with national standards. High-quality stainless steel thermos have smooth interiors, offer enhanced antioxidant properties, and provide peace of mind.
The art of tea is about humanity, and drinking tea is about savoring life. May every tea lover enjoy the convenience of modern life while experiencing the essence of traditional tea culture, finding a peaceful state of balance in the fragrance of tea. Don’t be bothered by false rumors; brewing tea in a stainless steel thermos is completely safe. Choose a thermos that suits your taste, fill it with your favorite tea leaves, and let the warm aroma of tea accompany your daily life—that’s the true pleasure of tea drinking.
