{
    "id": 1070312,
    "title": "Why does my fruit tea change colour?",
    "slug": "why-fruit-tea-changes-colour",
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    "url": "https://teas.co.uk/wiki/why-fruit-tea-changes-colour/",
    "modified": "2026-09-18T00:45:36+01:00",
    "excerpt": "Red fruit tea going purple or grey is usually your water, not a fault. How pH changes hibiscus and berry teas, and how to bring the red back.",
    "content_text": "Because most red fruit teas are, quite literally, a pH indicator. The red comes from anthocyanins \u2014 the pigments in hibiscus, berries, blackcurrant and red grape \u2014 and anthocyanins change colour with acidity:\r\n\r\n\r\n\r\nConditions\r\nColour\r\n\r\n\r\n\r\n\r\nAcidic (lemon juice, a tart blend, soft water)\r\nBright pink-red\r\n\r\n\r\nNeutral\r\nRed-purple\r\n\r\n\r\nAlkaline (hard water, bicarbonate)\r\nPurple, blue-grey, even greenish\r\n\r\n\r\n\r\nSo a hibiscus tea that glowed ruby at your friend's house and comes out dull purple in yours has not gone off. Your tap water is harder and more alkaline than theirs.\r\nThe one-second test\r\nSqueeze a little lemon into the cup. If the colour springs back to bright pink or red, it was pH, not a fault. That is also the easiest fix: a slice of lemon in the pot, or a filter jug for the kettle water.\r\nButterfly pea flower is the extreme version of the same effect \u2014 a deep blue infusion that turns purple the moment lemon hits it. Same chemistry, more dramatic.\r\nOther reasons the colour shifts\r\n\r\nHard water. Calcium and a higher pH dull everything, tea included. See tea in hard water.\r\nStanding. Anthocyanins fade with time, heat and light. A jug of iced fruit tea left in the sun loses its colour by the afternoon.\r\nIron. Traces of iron from an old kettle or a cast-iron pot can turn fruit teas grey-black.\r\nSteeping time. Longer brewing extracts more pigment, so the same tea can look pale at two minutes and deep at six.\r\nThe blend itself. A \"berry\" tea may be mostly hibiscus and rosehip, which is where the red really comes from. Read the ingredients \u2014 see fruit tea explained.\r\n\r\nIs a colour change a problem?\r\nNo. It is a pigment responding to its surroundings, not a sign of spoilage. Judge a fruit tea by its smell and taste: musty or fermented smells mean bin it, colour alone does not.\r\nWhat the colour does tell you is something about your water \u2014 and if your fruit teas look dull, your black tea is probably tasting duller than it should too. Hibiscus tea is the most colour-sensitive of the common ingredients.\r\nGetting a brighter cup\r\n\r\nUse filtered water if yours is hard.\r\nAdd a squeeze of lemon, or pick a blend with citrus or berry acidity in it.\r\nBrew it in glass if you like the look \u2014 you cannot see any of this in a mug.\r\nDrink it fresh; serve iced teas the day you make them.\r\n\r\nCommon questions\r\nWhy did my hibiscus tea turn blue?\r\nAlkaline water. Add lemon and watch it go pink again.\r\nDoes the colour change affect the taste?\r\nNot directly, though the same hard water that dulls the colour also flattens the flavour.\r\nIs blue tea a different plant?\r\nButterfly pea flower is a different plant, naturally blue and famous for the lemon trick. Blue-ish hibiscus is just chemistry.\r\nMy fruit tea is brown, not red. Why?\r\nEither the blend has little anthocyanin in it (apple, rosehip and orange are brownish), or it has aged. Check the ingredients first.",
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