很多人,包含公眾媒體, 總傳遞一個刻板印象, 認為第一泡用熱水沖洗, 能夠將農藥洗去, 避免過量的農藥下肚. 其實以台灣核准的農藥種類中, 大部分為脂溶性, 很難用水沖出農藥. 即使以台灣有使用之4種系統型農藥, 第一泡也需要喝到800公升才會產生問題 [1-2]. 只要農藥殘留符合法規, 健康是有保障的.
過去製茶過程的管控不夠嚴謹,難免會有一些塵埃污染茶葉. 儘管在殺菁過程溫度高達200多度以上, 能夠達到殺菌效果,但後續的整形,乾燥,團揉等製程若沒有管控得當, 灰塵一樣會有機會附著在茶葉上. 政府推出衛生製茶廠的評鑑考核, 認證製茶環境與製程管控, 除此之外, 還是必須仰賴製作過程中的衛生管理. 以烏龍茶為例, 茶葉成卷曲狀, 如果單純用第一泡沖洗茶葉, 若沒有把茶葉泡開, 根本不可能洗乾淨. 相反的, 若第一泡把整個茶葉泡開, 再倒掉茶水, 那不就代表最精華的營養元素都被倒掉了？
由於茶葉在初泡的過程中, 無論是條索狀或是球狀的茶葉, 都需要時間展開, 進而釋放味道. 溫潤泡的概念就是讓茶葉泡開, 讓接下來的沖泡味道能夠較為穩定, 否則直接泡第一泡, 可能會讓茶湯味道偏淡. 真的有必要嗎？
個人認為, 要保證第一泡味道不至於偏淡, 茶葉只需要多一點時間伸展, 口感不但不扣分, 健康元素也不至於被沖洗掉, 不是更好？第一泡時間拉長, 第二泡由於茶葉已展開, 要稍微縮短時間, 不用溫潤泡, 你一樣可以喝到好喝又健康的茶湯.
散茶以3-5分鐘的第一次浸泡, 營養成分釋出大約80-90%. 第二次沖泡後, 也差不多把剩下的10%析出了 [4-11]. 雖然洗茶時間不需要這麼長, 但營養在一開始的釋出是最多的, 你真的忍心倒掉具有抑癌作用的茶多酚, 可以降血糖的茶多糖, 使中樞神經興奮的咖啡鹼, 以及多種氨基酸, 維生素等營養物質嗎？
Is it necessary to wash the tea leaves by hot water before brewing? Of course NOT.
Clean up the pesticide residue? Wrong!
Lots of people, including news media and celebrities, always suggest the tea washing to remove the pesticide residue before the brewing. However, most of the pesticides approved by Taiwan government are fat-soluble. Hot water may not be able to wash them out. According to Taiwan pesticide residue regulation, in the worst case, it would be a health concern after drinking up to 800 liters of first steep tea [1-2]. In that case, pesticide doesn’t jeopardise your health but water. As long as the tea is proven following the regulation, I don’t see any health issue at all.
Wash out the dust?
In the past, the management of tea processing is not mature. Dusts might be introduced in tea. Even though the temperature of the fermentation fixing is around 200+°C, considering to eliminate most of bacteria, dusts may still contaminate the tea in the following process, such as shaping, drying, rolling, etc. Taiwan government offers the consulting and certificating service to improve the tea processing management . As long as the management of the processing is well controlled, tea quality is promised. Given some ball shape of tea leaves, like oolong, they take some time to stretch. if the steep time is short, the leaves may still curve. Dust cannot be removed completely. On the contrary, if the first steep dwells too long, you are not only washing away the dust but also the nutrition elements. Worthy?
Tea leaves takes time to stretch to release the flavour in water. Pre-brewing serves this purpose to promise the consistent flavour in the following steeps. The taste of the first steep may be too light otherwise.
To ensure the taste of the first steep without any pre-brewing, you simply extend the dwelling time to accommodate the leaves stretching. You can get a better taste without wasting the nutrition elements. Why not?
Still healthy after leaves washing?
Yes but you may lose a lot of nutrition elements. The study shows the loose tea releases around 80-90% nutrition elements by 3-5mins in the first steep. Almost 100% nutritions are released in second steep [4-11]. The loss of the nutrition by washing leaves is expected, even within a small time interval. Do you still want to wash away the nutritions, like tea polyphenol, amino acid, vitamins, etc?
-Research team @ 茶水部 LittoTea, 澄萃茶藝.