Mountain pepper or pepper berry trees are a tall evergreen shrub to small tree of up to 10 m high. There are separate male and female plants (dioecious). The trunk is straight, with many branches arising at acute angles. The distinctive reddish branches are thick and hairless, with dark brown, smooth outer bark with rough ridges running down from the base of each leaf. The under bark is also dark brown and very thin.
The leathery leaves of mountain pepper contain hot-tasting compounds (polygodials) resulting in an unusual fragrant, spicy flavour. The berries initially have a sweet taste, which is closely followed by an intense pungency, giving way to a sensation of numbness. The leaves and berries are currently used in Australia to add a spicy bush food flavour to many foods. They are used to flavour curries, cheeses, wines, salad dressings and some boutique alcoholic beverages and as a substitute for black pepper. Research on this species has revealed that the polygodials present in mountain pepper have unique anti-microbial and antifungal properties. It is thought that mountain pepper may have economic potential as a herbal medicine, as it is closely related to a South American species used for preparing rare herbal remedies.
Since the late 1980s, there has been a lot of interest from both local and international markets in mountain pepper due to its unique character and 'natural' status. Semicommercial quantities of extract are currently provided to Japan, and used as a flavouring and fragrance and added to products such as wasabi paste.