The tea plants used to produce “ Taiwanese-style ” oolongs in mainland China and Vietnam were imported from Taiwan about a decade ago, and are therefore genetically very similar to Taiwanese tea. According to the COA: “ The technology needed to determine the country of origin of tealeaves is not yet mature. At the moment, we can only assess their quality based their appearance and the judgment of our own five senses. ”
因為大陸和越南生產的「台式烏龍茶」，說穿了都是 10 年前從台灣移去的，DNA 自然與台灣茶相同，農委會的官方說法則是：「目前茶葉原產地鑑定技術未臻成熟，僅能以外觀及官能品評方式，進行品質優劣的分級。」