Color-Changing Butterfly Pea Flower Tea

Before you start

Butterfly pea flowers come from a climbing vine common in Southeast Asia, where they are used to tint rice, desserts and drinks. Steeped in hot water they give a startling cobalt-blue tea with a mild, woody, faintly earthy flavor. On its own the taste is gentle; the drama comes from color.

The pigments in the flower react to acidity. In plain water the tea is blue; add lemon or lime juice and the color shifts through violet to magenta as the drink becomes more acidic. That makes the tea a natural base for lemonades and layered iced drinks. Because the flower itself tastes so subtle, the key decisions are what you pair it with: honey, lemongrass, ginger or a citrus syrup all give the drink character while letting the color show.

Ingredients

• 2 g (about 20 dried flowers, or 2 tsp) dried butterfly pea flowers
• 500 ml (2 cups) water, heated to 90 to 95°C (194 to 203°F)
• 15 to 30 ml (1 to 2 tbsp) honey or simple syrup — to taste
• 30 ml (1 oz) fresh lemon or lime juice — added at the table for the color change
• 1 stalk lemongrass, bruised — optional, for aroma

Method

1. Heat the water until small bubbles rise steadily, about 90 to 95°C (194 to 203°F). Boiling water is fine too, but slightly cooler water keeps the flavor softer.
2. Put the flowers and the lemongrass, if using, in a glass teapot or jug. Pour in the water.
3. Steep for 5 minutes. The water turns blue within seconds and deepens to an inky sapphire. Longer steeps make the color darker without much extra flavor.
4. Strain into clear glasses and stir in honey or syrup. Sweetening before the citrus matters, because it is hard to dissolve honey later in a cold drink.
5. Serve the lemon or lime juice in a small pitcher. Pour about 15 ml into each glass and watch it turn violet; add more for a pinker hue.
6. For iced tea, brew at double strength (4 g flowers in 500 ml), cool it, and pour over ice before adding citrus.

Tips for success

• Use clear glassware. Half the appeal is watching the color move through the drink.
• For a layered look, fill the glass with ice and lemonade first, then slowly pour cold blue tea over the back of a spoon.
• Flower quality varies. Deep-blue, whole, dry flowers give the strongest color; faded gray ones give a dull tea.
• Store the flowers airtight and away from light, which fades the pigment.

Substitutions

Lemon or lime juice

Any acid shifts the color: yuzu juice, passion fruit, tonic water or a splash of lemonade. Tonic gives a blue-to-lavender shift and a bitter edge.

Dried flowers

Butterfly pea powder dissolves instantly; use about ¼ teaspoon per cup. Pre-blended butterfly pea tea bags often include lemongrass or green tea.

Honey

Simple syrup keeps the color clearest. Brown sugar and dark honey tint the tea slightly green.

Variations

Blue lemonade

Fill a glass with ice and lemonade, then float chilled double-strength butterfly pea tea on top.

Butterfly pea latte

Steep 2 g flowers in 60 ml hot water, strain, add honey and top with 180 ml steamed milk for a pale blue latte.

Butterfly pea and ginger

Add 3 thin slices of fresh ginger to the steep for warmth.

Troubleshooting

The tea is green instead of blue

The water is alkaline, or a yellow-toned sweetener was mixed in. Try filtered water and a clear syrup.

The color change is weak

The tea is too dilute or there is not enough acid. Steep more flowers and add citrus a little at a time.

It tastes like hay or nothing at all

That is the flower's natural mild flavor. Add lemongrass, ginger, mint or a flavored syrup to give it more character.

Storage

Brewed butterfly pea tea keeps in a covered jar in the refrigerator for up to 3 days, though the blue slowly fades. Add citrus only to the glass, not the stored tea. Keep dried flowers airtight in a cool, dark cupboard.

Safety notes

Butterfly pea flower tea is caffeine-free. Research on regular consumption is limited; if you are pregnant, nursing or take medication, ask a health professional before drinking it often.