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    "id": 1070314,
    "title": "Why does green tea turn yellow or brown?",
    "slug": "why-green-tea-turns-yellow-or-brown",
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    "url": "https://teas.co.uk/wiki/why-green-tea-turns-yellow-or-brown/",
    "modified": "2026-09-18T19:38:37+01:00",
    "excerpt": "Green tea is meant to brew yellow-gold, not bright green. Here is why a cup turns brown \u2014 stale leaf, water too hot, hard water or time \u2014 and how to fix it.",
    "content_text": "Most green tea is supposed to brew yellow-gold. \"Green\" describes what happens to the leaf, not the colour of the drink: the leaves are heated early to stop them oxidising, which keeps them green and fresh-tasting. The liquid they make is usually pale yellow, gold or yellow-green.\r\nSo a golden cup is normal. What is worth investigating is a cup that turns brown, or one that has changed from how that same tea used to look.\r\nThe five usual causes\r\n\r\n\r\n\r\nWhat you see\r\nMost likely cause\r\nWhat to do\r\n\r\n\r\n\r\n\r\nGolden or yellow-green from the start\r\nNormal for most green tea\r\nNothing\r\n\r\n\r\nBrown and flat-tasting, straight from the pack\r\nStale leaf\r\nBuy smaller, fresher packs and store them properly\r\n\r\n\r\nDark and bitter\r\nWater too hot or brewed too long\r\n70\u201380\u00b0C, 1\u20132 minutes\r\n\r\n\r\nDarkens while it stands\r\nOxidation in contact with air\r\nDrink it fresher, or chill it\r\n\r\n\r\nBrown but tastes toasty and sweet\r\nA roasted tea, by design\r\nNothing \u2014 that is hojicha\r\n\r\n\r\n\r\n1. Age. Green tea goes stale faster than black\r\nThis is the most common cause of a genuinely brown cup. Green tea has not been oxidised during manufacture, so it carries on slowly oxidising on the shelf \u2014 especially in warmth, light, damp or open air. Old leaf loses its fresh grassy smell, browns in the cup and tastes flat and papery.\r\nGreen tea is at its best within a few months of opening. Keep it in an airtight, opaque container somewhere cool, dark and dry, away from strong smells, and do not decant it into a pretty glass jar on a sunny shelf. Our storage guide has the full routine.\r\n2. Water that is too hot\r\nBoiling water scalds green tea. It pulls out more colour and more bitterness, so the cup comes out darker and harsher than it should be. Aim for 70\u201380\u00b0C: either use a variable-temperature kettle, or boil and check with a thermometer as the water cools.\r\nBrewing time matters just as much. One to two minutes is plenty for most green teas; a five-minute steep turns it dark and astringent.\r\n3. Hard water\r\nIn hard-water areas the higher mineral content and pH make tea darker and duller, and green tea shows it more than black. Research comparing brewing waters found green tea infusions made with higher-pH, higher-mineral water darkened faster on contact with air. Brewing water and tea properties, Food Chemistry\r\nA simple filter jug often brightens both the colour and the taste. A squeeze of lemon lightens the colour too, because acid changes how the tea's compounds absorb light \u2014 that is why iced tea goes pale when you add lemon.\r\n4. Standing around\r\nBrewed tea keeps reacting with the air. A cup poured half an hour ago will look browner than it did at the start, and a jug of iced green tea left out overnight will be noticeably darker. It is the same process that turns a cut apple brown. Brew what you will drink, and keep cold brews covered in the fridge.\r\n5. It might not be a fault at all\r\nSome teas are brown on purpose. Hojicha is green tea roasted until it is reddish-brown, and it should taste toasty and sweet rather than grassy. Genmaicha, with its toasted rice, brews golden.\r\nStyle matters too: Japanese steamed teas such as sencha brew greener and slightly cloudy, while Chinese pan-fired teas such as Mao Feng brew clearer and more golden. And matcha is not comparable to any of them \u2014 it is whole leaf powder suspended in water, which is why it is opaque and vivid green.\r\nGetting a brighter cup\r\n\r\nStart with fresh leaf from a pack you opened recently.\r\nUse filtered water if yours is hard.\r\nCool the water to about 80\u00b0C.\r\nBrew 1 to 2 minutes, then remove the leaves or bag.\r\nDrink it fresh.\r\n\r\nTwinings Pure Green Tea is a simple everyday bag to test this with. For a Chinese loose-style leaf with a more golden cup, try Teapigs Mao Feng Green Tea. Full method in how to brew green tea.\r\nCommon questions\r\nIs brown green tea safe to drink?\r\nYes. Stale tea is a flavour problem, not a safety one. Throw it out if the leaves smell musty or damp, or show any mould.\r\nWhy is my bagged green tea darker than loose leaf?\r\nTea bags contain smaller particles, which release colour and tannin much faster. The same brewing time gives a darker cup.\r\nHas my green tea turned into black tea?\r\nNo. Black tea is made by deliberately oxidising fresh leaves during manufacture. A stale or badly brewed green tea is just a tired green tea.\r\nShould the leaves be green after brewing?\r\nWet green tea leaves usually stay olive to deep green. Leaves that unfurl brown and brittle point to old or heat-damaged tea.",
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