Benzoin Siam (Styrax tonkinensis) is a semi-deciduous species of tree found in the forests of Vietnam, Thailand, Laos and Cambodia. Trees grow up to 30 meters tall, with pointed leaves and clusters of fragrant white flowers. Measured incisions can be made on the trunks of adult trees to harvest the aromatic resin, which has potent notes of vanilla and spice. The resin is used in incense, cosmetics, soaps, and also as a flavour ingredient in some foods.

Botanical name: Styrax tonkinensis

Other names: Gum benjamin, gum benzoin, benzoin Siam, loban, storax

Main constituents: Benzyl benzoate, benzyl alcohol, benzoic acid, ethyl cinnamate.