Stop Dumping the First Steep: What Science Says About Rinsing Tea

Brewing & Storage｜Author：祥興茶行｜Published：2026-07-15

Rinsing tea to wash off pesticides removes far less than most drinkers assume, and compliant teas are already safe unrinsed. Here is what the first infusion holds, and when a warming pour is worth doing for flavor.

Many people pour hot water over their tea leaves, wait a few seconds, and tip the liquor out, usually because "the first infusion is the dirtiest and rinsing washes off the pesticides." In fact, official tea evaluators drink the first infusion, and what you pour away is often the freshest infusion in the whole pot.

This piece uses primary research and official sources to look at whether the first infusion should go, and separates two moves that often get lumped together: rinsing (for cleanliness) and awakening the tea, or the warming pour (for flavor).

The Short Answer: Dumping the First Steep Does Little Against Pesticides

A 2019 study in the food-science journal _Journal of Agricultural and Food Chemistry_ tested eight insecticides in green, black, and oolong teas. With a rinse of 5 to 30 seconds, the share of pesticide that moved into the rinse water was only 0.2% to 24%, and for most it was very low [1].

Whether a pesticide rinses off depends on its octanol–water partition coefficient (log P), a measure of whether a molecule prefers water or oil. According to the tea research station's official material, a log P above 1 leans lipophilic (oil-loving); below 1 leans hydrophilic (water-loving) [7]. Hydrophilic pesticides (low log P, highly soluble in water), such as the neonicotinoids imidacloprid (log P 0.57) and acetamiprid (0.80), are somewhat easier for hot water to carry away. Strongly lipophilic pesticides (high log P, almost insoluble in water), such as the pyrethroids bifenthrin and cyhalothrin (log P as high as 6–7) or chlorpyrifos (4.7), hardly rinse off at all [1][7].

Lipophilic pesticides have a high log P. They behave like oil, do not mix readily with water, and have extremely low water solubility (mostly below 0.001% in Table 1). They barely dissolve into the liquor in the first place, so whether you rinse or not, you take in almost none of them from the liquor. Rinsing the first infusion to guard against lipophilic pesticides accomplishes very little in practice [1][7].

📖 A quick word on terms: water-soluble/fat-soluble describes the degree of solubility (how much dissolves); hydrophilic/lipophilic uses log P to describe a molecule's preference for water versus oil. The two are closely related (the more lipophilic, generally the less water-soluble), but they are not the same thing. The tea station's article uses both: "water-soluble and fat-soluble" in its title, log P for the precise definition [7].

As for Taiwan's tea gardens, the Ministry of Agriculture's Tea and Beverage Research Station (formerly the Tea Research and Extension Station) states that pesticides approved for tea plants are "high in safety and low in water solubility," mostly lipophilic [2][7]. Of the 75 tea-garden pesticides the station catalogued, only five (dinotefuran, methomyl, cartap, glyphosate-isopropylammonium, and paraquat) are both hydrophilic (log P

The study's authors do recommend rinsing, but what they recommend is the 5-to-30-second warming pour of oolong gongfu brewing. Their results show unrinsed tea is already safe, and a short rinse only lowers exposure a little further [1].

Rinsing vs. Awakening: One Word Apart, Opposite Aims

Many people treat rinsing and awakening the tea (the warming pour) as the same thing. Their purposes are entirely different.

Rinsing (a hygiene aim): the goal is to wash off dirt or pesticides. It does little for compliant tea, and official tea evaluation does not discard the first infusion [1][2].

Awakening the tea / the warming pour (a flavor aim): the goal is to rouse the leaves, let them unfurl, draw out the aroma, and even out the temperature. It is a brewing technique done for taste, with nothing to do with cleaning. The tea station describes the move as filtering off tea froth and "helping the tea's character come through sooner" [2].

〔圖〕Diagram contrasting rinsing with awakening the tea

A simple way to sort them: tight teas that need waking deserve a priming pour, for flavor rather than cleaning; tender teas whose freshness comes early are at their brightest in the first infusion, so keep it.

The rinsing habit is old. According to historical tea manuals, once loose-leaf brewing became popular, people began pouring hot water over the leaves first to "remove dust and cold air," clearing away tea dust and waking the leaves at the same time, in an era before pesticides existed [6]. The warming pour of gongfu tea in Fujian, Guangdong, and Chaoshan later developed along this same line of rousing the leaves and lifting the aroma into a signature technique [6]. What earlier tea drinkers called rinsing was closer to what we now call awakening.

The First Infusion You Pour Out Is Often the Freshest

The compounds that make tea taste fresh dissolve the fastest.

A 2015 study of green-tea brewing observed that catechins dissolve fastest in the first 3 to 5 minutes, and caffeine faster still, peaking at around 3 minutes with little change after that however long the steep continues [4]. That study used tea bags and a single long steep, which differs from the repeated short infusions of gongfu brewing, so "the first infusion is the freshest" is an inference drawn from it; the individual compounds were not measured under gongfu conditions [4]. Caffeine and amino acids (such as theanine, the source of tea's savory sweetness) are highly water-soluble and sit near the leaf surface, so the most of them comes out at the start of brewing.

💡 Dumping the first infusion pours away the freshest caffeine, amino acids, and a share of the catechins, a real loss with delicate green teas and bud-grade teas. The 2019 study also showed that a short warming pour removes only 0% to 11% of the beneficial compounds, a small loss [1].

For more on how these compounds are extracted, see our piece on why cold-brew tea tastes less bitter and has less caffeine.

Myth vs. Reality

What you often hear ｜ What research and official sources say

Rinsing washes all the pesticides away ｜ Only water-soluble pesticides rinse off, and only partly; fat-soluble ones barely rinse off, and the agents commonly used on Taiwanese tea are mostly fat-soluble [1][2]

Not drinking the first infusion is safer ｜ Official tea evaluation never discards the first infusion, and there are no known cases linking residue violations to whether the first infusion was poured out [2]

The first infusion is the dirtiest and least nutritious ｜ The opposite: the freshest caffeine, amino acids, and a share of the catechins dissolve most heavily early on [4]

Rinsing equals awakening, so always do it ｜ Their aims differ; awakening is a flavor technique, and using it on tender bud green teas is a waste [2]

Which Teas Get a Priming Pour, and Which First Infusions to Keep

A priming pour suits them: the leaves are tight and need waking Pu-erh and other compressed teas (cakes, tuo, bricks), ball-rolled high-mountain oolongs, heavily roasted oolongs, aged teas. The aim is to help the leaves unfurl, draw out the aroma, even out the heat, and clear storage mustiness. It is a flavor consideration, not a hygiene one [2].

Keep the first infusion: the freshness comes early Fine green teas, bud and silver-tip teas, delicate white teas. Their first infusion carries the richest and freshest caffeine, amino acids, and catechins, so pouring it out is the biggest waste [4][1].

The Takeaway

  1. Dumping the first infusion out of fear of pesticides does little for compliant tea: only water-soluble pesticides rinse off at all, fat-soluble ones barely dissolve into the liquor to begin with, and official evaluators drink the first infusion [1][2].
  2. Residue is not the same as exceeding the limit: even unrinsed, compliant tea keeps pesticide exposure far below the safety threshold, so pouring out the first infusion is wasted effort that also throws away the good part [1][3].
  3. Rinsing and awakening are two different things: compressed, roasted, and aged teas deserve a priming pour because it makes them taste better; tender green teas should keep their first infusion because it is the freshest [2][4].

References

  1. Gao, W., Yan, M., Xiao, Y., Lv, Y., Peng, C., Wan, X., & Hou, R. (2019). Rinsing Tea before Brewing Decreases Pesticide Residues in Tea Infusion. _Journal of Agricultural and Food Chemistry_, 67(19), 5384–5393. https://doi.org/10.1021/acs.jafc.8b04908
  2. 農業部茶及飲料作物改良場（前身行政院農業委員會茶業改良場）. 茶葉食安問答集：「茶葉的第一泡到底能不能喝？與農藥殘留是否有關」. 農業部食農教育資訊整合平臺. https://www.moa.gov.tw/faq_view.php?id=8
  3. 陳宗懋（中國工程院院士）訪談整理. 茶葉農殘：殘留 ≠ 超標. 科信食品與健康信息交流中心. https://www.kexinzhongxin.com/html/huati/3101.html
  4. Saklar, S., Ertas, E., Ozdemir, I. S., & Karadeniz, B. (2015). Effects of different brewing conditions on catechin content and sensory acceptance in Turkish green tea infusions. _Journal of Food Science and Technology_, 52(10), 6639–6646. https://pmc.ncbi.nlm.nih.gov/articles/PMC4573099/
  5. Xiao, Y., et al. (2025). Rinsing tea reduces the health risk of neonicotinoids in the tea infusion. _Environmental Chemistry and Ecotoxicology_, 7. https://doi.org/10.1016/j.enceco.2025.06.010
  6. 明清泡茶法與工夫茶溫潤泡文化綜述（據明代茶書記載，如錢椿年／顧元慶《茶譜》、張源《茶錄》相關段落，二手轉引待核）. 澎湃新聞・私家歷史；福建日報〈洗茶，必不可少還是多此一舉〉. https://www.thepaper.cn/newsDetail_forward_8826807 ；https://www.fjdaily.com/app/content/2022-07/14/content_1520703.html
  7. 黃玉如. 農藥的水溶性與脂溶性簡介.《茶業專訊》第 100 期（2017 年 6 月）. 農業部茶及飲料作物改良場. https://www.tbrs.gov.tw/

Teas mentioned