Butterfly pea flower tea is a caffeine-free herbal infusion brewed from dried Clitoria ternatea flowers, producing an intensely vivid deep blue liquor due to anthocyanin pigments in the petals. The tea’s most striking characteristic is its dramatic pH sensitivity: adding any acidic ingredient — lemon juice, lime, hibiscus — shifts the colour instantly from blue through purple to bright pink or red, a property that has driven significant interest in specialty coffee shops and culinary applications.
In-Depth Explanation
The plant:
Clitoria ternatea (butterfly pea, blue pea, Asian pigeonwings) is a climbing vine native to tropical Southeast Asia and cultivated widely across Thailand, Vietnam, India, and the Philippines. The deep blue flowers are named for their resemblance to the female clitoris — a botanical naming convention that is sometimes noted with amusement but is simply standard taxonomic practice. It has distinct traditional uses in Ayurvedic medicine (known as shankhpushpi in Sanskrit) and Southeast Asian traditional medicine.
The colour chemistry:
The blue colour comes from anthocyanins — specifically ternatins (acylated delphinidin-based anthocyanins) — which are among the most stable blue pigments found in plants. These anthocyanins are highly pH-sensitive:
| pH | Colour |
|---|---|
| ~7 (neutral water) | Deep blue |
| ~5–6 (slightly acidic) | Purple/violet |
| ~3–4 (acidic; lemon juice) | Magenta/pink |
| ~2 (strongly acidic) | Red |
This property makes butterfly pea flower tea a natural pH indicator and an exceptionally versatile ingredient for colour-changing cocktails, mocktails, and food products.
Cultural context:
- Thailand: Known as dok anchan (ดอกอัญชัน); widely used in traditional Thai cuisine for blue rice, blue noodles, and herbal drinks. It is a standard herbal tea in Thai traditional medicine.
- Southeast Asia broadly: Used to colour rice (nasi kerabu in Malaysia; blue glutinous rice across the region) and as a medicinal herb for memory and hair health.
- Modern global trend: The visual drama of the colour-changing property drove viral social media interest from approximately 2017–2020, making it a mainstay of Instagrammable specialty drink menus worldwide.
Health claims:
Butterfly pea flower is promoted for a variety of health benefits in both traditional medicine and modern wellness marketing:
- Cognitive support: Several studies have investigated ternatin and other butterfly pea compounds for potential neuroprotective effects.
- Antioxidant activity: High anthocyanin content = high measured antioxidant capacity (by standard assays).
- Anti-inflammatory: Shown in animal models; human clinical evidence is limited.
- Glycaemic effects: Some studies suggest glycaemic response modulation; evidence is preliminary.
The FDA classifies Clitoria ternatea flower extract as generally recognised as safe (GRAS) as a colour additive.
History
Clitoria ternatea has been cultivated and used in Ayurvedic medicine for centuries, with textual records describing its use for cognitive enhancement, anxiety, and hair loss. In Southeast Asia it became embedded in culinary culture as a natural food dye before modern synthetic colourants were available. Its global rise as a specialty tea and drink ingredient largely followed the social media food photography trends of the 2010s, when the colour-changing lemonade and gin-and-tonic applications gained widespread viral attention.
Common Misconceptions
“Blue tea is a type of tea like green tea or black tea.” Butterfly pea flower tea contains no Camellia sinensis leaves. It is a tisane/herbal infusion. It is not related to any traditional tea processing category. The “blue tea” marketing label is entirely about the colour.
“Mixing it with lemon creates a chemical reaction.” The colour change is simple acid-base chemistry (anthocyanin pH sensitivity), not a chemical reaction in the sense of a new substance forming. The taste changes slightly (it becomes slightly more tart) but the change is primarily visual.
Taste Profile & How to Identify
Aroma: Mild, earthy, slightly woody; subtler than most other floral teas.
Flavour: Very light; slightly earthy, faintly sweet, almost neutral — the appeal is primarily visual.
Colour: Vivid deep blue (fading to purple, pink, or red with acid).
Mouthfeel: Very light body, watery.
Brewing Guide
| Parameter | Value |
|---|---|
| Flowers | 8–15 dried flowers per 250ml |
| Water temperature | 90–95°C |
| Steep time | 5–10 minutes (longer = deeper blue) |
| Infusions | 1–2 |
Steep longer than most teas for maximum colour intensity. Add lemon or lime juice at the table for the colour-change effect. Cold brew (overnight) produces excellent results. Does not work well in alkaline (hard) water — the blue will shift to greenish.
Last updated: 2026-04
Related Terms
See Also
Research
- Nair, V., et al. (2012). Clitoria ternatea and the CNS. Pharmacognosy Reviews, 6(12), 141–153.
[Reviews pharmacological evidence for butterfly pea’s traditional use as a cognitive and neurological herb, covering the alkaloid and flavonoid content.]
- Siti Azima, A.M., et al. (2017). Phenolics, anthocyanins and characterization of antioxidant activities in butterfly pea flower. Asian Pacific Journal of Tropical Biomedicine, 7(4), 352–359.
[Quantifies the ternatin anthocyanins responsible for butterfly pea’s distinctive colour and documents their antioxidant capacity.]