When drinking tea, you may notice that once it cools down, the tea broth becomes murky and doesn't taste as good as when it was freshly brewed. However, cold-brewed tea remains sweet and refreshing even after a long soak. Why is this? Today, let's explore the “secret” behind this phenomenon together!

In simple terms, hot tea has a higher temperature, which causes molecules to move faster, resulting in a more fragrant aroma and better taste. Once the temperature drops, however, the polyphenols and vitamins in the tea are more prone to oxidation, decreasing their content. Consequently, the taste isn't as pleasant as when it was first brewed.

What is Cold-Brewed Tea?

Unlike regular tea, one key difference with cold-brewed tea is its lower initial temperature, which reduces the likelihood of oxidation of its internal substances. Additionally, the internal substances extracted from cold-brewing are fewer than those from hot brewing, so there isn't a significant difference in taste even after being left for some time.

The experience with hot-brewed tea, however, is highly dependent on temperature. If a cup of tea is left for a while, its color turns brownish and murky. This is primarily due to the decrease in temperature affecting the caffeine and catechins in the tea. Although these substances are not harmful to the human body, they do affect the overall drinking experience.

What Are the Differences Between Hot-Brewed and Cold-Brewed Tea?

Theoretically, hot brewing extracts nutrients more effectively than cold brewing. Different types of tea require different water temperatures for brewing. For example, green tea is best at 80-90 degrees Celsius, while Oolong tea requires water above 95 degrees Celsius. Under high temperatures, more caffeine and other internal substances are released from the tea leaves.

Research shows that cold-brewed tea contains approximately 20% less caffeine compared to hot-brewed tea. Therefore, for those who enjoy tea but are sensitive to caffeine, cold-brewed tea is an excellent choice. It can be prepared using mineral water or cooled boiled water, making it a convenient method, especially popular among younger people and office workers.

Choosing the Right Type of Tea

Generally, the longer the fermentation degree of the tea, the longer it takes for its essence to be extracted during cold brewing. Therefore, we recommend choosing teas with lower fermentation degrees such as green tea, White Tea, certain black teas, oolong teas, and herbal teas for cold brewing.

Green Tea: Green tea is fresh and fragrant; cold brewing reduces bitterness, enhancing its sweetness. Huangshan Maofeng and West Lake Longjing, both high-quality green teas, offer a unique flavor when cold-brewed.

White Tea: For white tea, Bai Hao Yin Zhen (Silver Needle) and Bai Mudan (White Peony) are recommended for cold brewing because of their prominent downy fragrance.

Black Tea: Black tea is naturally sweet and suitable for cold brewing, though not all black teas are ideal. Yunnan black tea and Yingde black tea, known for their clear and sweet flavors, are recommended. Teas like Lapsang Souchong, which have a distinct smoky aroma, are better suited for hot brewing.

Oolong Tea: Oolong tea is known for its rich and enchanting aroma. Cold brewing does not easily release the aroma, so we recommend choosing lightly scented oolong teas, such as Dongding Oolong and lightly scented Tieguanyin. Wuyi rock teas are better appreciated when hot-brewed to showcase their full flavor profile.

Herbal Tea: There are many types of herbal teas, including jasmine tea, osmanthus Longjing, osmanthus black tea, and peach oolong, which are all great choices for cold brewing.