Buddleja officinalis – Natural yellow food dye
Buddleja officinalis is a small deciduous early-spring flowering shrub of the family Scrophulariaceae (figwort). Its “official” Vietnamese name is “mật mông hoa“, however the plant is better known by some ethnic minorities in Vietnam who call it “phón” or “Bjoóc phón“. Its flowers are used as a natural yellow food dye.
- Family: Scrophulariaceae
- Genus: Buddleja
- Species: Buddleja officinalis
- Vietnamese name: Mật mông hoa, Bjoóc phón (local name), Bó phón, Phón
B.officinalis is a small shrub with young branches bearing a lot of white or brownish furs which grow very quickly as well as some “excretory” hairs. Its leaf shape is ovate or elongated, slightly narrow at the bottom, pointed at the apex. Its leaves are about 6 – 11cm long, 2 – 4cm wide, smooth on the upper surface, and hairy on the bottom. Its flowers are about 15cm long. The flowering season starts in February – March, while the fruiting season starts in July – August.
In Vietnam, B.officinalis can be found in several mountainous northern regions. It grows naturally on the edge of the forest, on the slopes of the fields.
Buddleja officinalis can be used as a medicinal herbs in some local trational medicine practice, but the plant is best known as a natural food dye. In Vietnam, there many natural food dye from the leaves, flowers, fruits or tubers of local plants, and the flowers of B. officinalis is one of them. Phón flowers has a sweet scent like honey (the official Vietnames name does reflect this). Its flowers bloom from mid-February to the end of March every year.
The flowers are white, but when heated, they will turn yellow and have a very fragrant smell, so the local people (like the Tai, and Nung minorities) often use them to cook sticky rice. These Buddleja flowers can be dried as a commercial product and used gradually for the whole year.
First, the flowers are cooked in a pot of water to get the flower “juice”. Rice will be soaked in this flower water for sometimes before getting steamed.