Butterfly pea flower gin gets its deep indigo colour from a flower that has been in Southeast Asian kitchens for generations. Add citrus and it turns violet. That is not a gimmick. It is a chemical reaction, and once you understand it, you see it differently in the glass. At Brass Lion, we pair butterfly pea flower with lavender in our Butterfly Pea Gin. Floral and quietly earthy, built as much for what it does when you pour as for what it tastes like.
Where Does Butterfly Pea Flower Come From?
The flower is Clitoria ternatea, native to tropical Asia, and it has been used in the region's food culture long before cocktail menus discovered it. In Peranakan cuisine, it dyes rice and kueh a deep natural blue. Nyonya blue rice, found at hawker centres across Singapore, gets its colour from exactly this flower. It turns up in Thai cold drinks, nyonya desserts like kueh salat, nasi lemak, and a hundred everyday preparations across Southeast Asia.
That history matters to us. The butterfly pea flower in our Butterfly Pea Gin is not a novelty ingredient from a food trend report. It is something generations of people in this city have cooked with, eaten, and grown up around. We chose it because it belongs here — which is the same reason we chose most of our botanicals. If you want to go deeper on the botanical choices behind our gins, our guide to Singapore gin botanicals covers the full picture.
Why Does the Colour Change?
The answer comes down to the behaviour of pigments called anthocyanins — the same compounds that make purple cabbage go pink in vinegar, or red berries deepen in colour as they ripen. Butterfly pea flower is full of them. At a neutral pH, anthocyanins sit blue. Add acid and the molecular structure shifts, taking the colour with it.
Citrus is the most direct trigger. A squeeze of lime is enough to watch the gin shift from indigo to violet in real time. Tonic water does the same thing because most tonic contains citric acid, though not all varieties do, so it is worth checking the label. Plain soda is neutral and leaves the colour alone. The shift does not reverse. Once the acid goes in, the colour settles where it lands.
Even though it’s repeatable, predictable chemistry, it’s still a little surprise every time.
What Does Brass Lion's Butterfly Pea Gin Taste Like?
The colour catches the eye first. Then there is the question of whether the gin itself is worth drinking.
Our version pairs butterfly pea flower with lavender. On the nose, lavender leads — clean, slightly sweet, unmistakably floral. The butterfly pea adds earthiness underneath, grounding the floral character without fighting it. On the palate you get citrus brightness first, then a soft honey-like quality from the lavender, then a mellow finish that clears quickly. Nothing lingers too long. Nothing dominates.
Aromatic, floral, delicate, in that order. The SIP Awards 2019 Double Gold it received recognised that balance.
How Should You Serve It?
The serve that shows the gin at its best is elderflower tonic, a slice of grapefruit, and a sprig of rosemary. Pour the tonic first, then add the garnish, and watch for the moment the citrus from the grapefruit hits the gin. Some people pour slowly on purpose. That is completely understandable.
If you want to see what the gin does in a cocktail, the Peranakan 75 is the natural starting point. It is our take on the French 75, citrus-led and effervescent, and the colour shifts visibly as you build it. You can find the full Peranakan 75 recipe here. Brass Lion Butterfly Pea Gin is available to order here.
FAQ
Does butterfly pea flower taste like flowers?
Not exactly. It reads more earthy than floral, and it is fairly subtle on its own. In our version, lavender provides the obvious floral character. The butterfly pea works quietly underneath, rounding out the profile rather than announcing itself.
Will any mixer change the colour?
Only acidic ones. Tonic water and citrus juice shift the colour because they contain citric acid. Still water and soda are pH-neutral and leave it alone. The higher the acid content, the more dramatic the shift.
Is the colour shift completely natural?
Yes. No added colouring in Brass Lion Butterfly Pea Gin. The indigo comes entirely from the butterfly pea flower, and the colour change is the same natural reaction to acidity that happens when this flower is used in Peranakan cooking.
