Because once directly heated, the "freshness" of winter wine has changed, and the taste has changed accordingly.
Suzhou winter brewing was originally called dongyang wine, which was named after the rising of yang spirit after the winter solstice. According to the lunar calendar, the winter solstice is the most important solar term in a year, because after this day, the yang rises and everything begins to recover slowly.
So there is a saying that "the winter solstice is bigger than the New Year". Due to the popularity of local wine-making in Dongyang, Zhejiang Province after the Song Dynasty, and Ma Zhiyuan's "Dialing Constantly" in the Yuan Dynasty, "Chrysanthemum blossoms" are coming back.
Accompanied by the West Monk of Tiger, Crane Lin You and Longshan Guest; Like Du Gongbu, Tao Yuanming and Li Taibai; There are Dongting oranges, Dongyang wine and West Lake crabs. And Li Shizhen's Compendium of Materia Medica in the Ming Dynasty, "Dongyang wine is good for drinking and taking medicine", which confused the two different concepts.
So we can see that ancient scholars in Wu often wrote "Dongyang wine", while scholars in other areas often wrote "Dongyang wine".
After the Japanese occupation, people often made "Oriental wine" (mistaken for Japanese wine). Until recent years, merchants have made it famous from "Wu Hao" that "winter wine is white in October, please see the wood broom hanging on the eaves." For a while, wine was used to discuss flavor, and I didn't like the ball navel but only the tip. I discovered the word "winter brew".