Tea Seed

Camellia oleifera is an evergreen shrub or small tree, 2 to 6 metres tall, with glossy dark leaves and white flowers that open in autumn and early winter. Its round, woody capsules ripen a year later, splitting to release between one and several dark brown, rounded seeds. The kernels inside are rich in oil. The tea plant itself, Camellia sinensis, also produces similar seeds, but those are used for oil less often. The seeds are not eaten raw like nuts; they are shelled, dried and pressed, producing a pale golden oil with a mild, faintly nutty aroma.

Camellia oleifera is native to southern China and nearby parts of Southeast Asia and has been cultivated for centuries in provinces such as Hunan, Jiangxi, Guangxi, Zhejiang and Fujian. Millions of hectares are planted in China today, and the government has promoted the crop as a source of domestic edible oil. Related camellias are grown for oil in Japan, Vietnam and Korea. The tea plant, Camellia sinensis, is native to the border region of southwestern China, northern Myanmar and northeastern India.

Tea seed oil is described in Chinese records as a cooking and lamp oil with a very long history, and people in Chinese mountain communities have pressed it for many centuries. In Japan, the seed of Camellia japonica yields tsubaki oil, long used in hair care and, to some extent, food. The oil is often compared with olive oil because it is rich in oleic acid.

In recent decades interest in tea seed oil has increased well beyond southern China. It is promoted as a healthy, high-smoke-point oil that suits stir-frying and deep-frying, and bottled products are exported to Asian markets and the West. The pressed seed cake has its own uses. It contains saponins, soap-like compounds, and is traditionally used as a natural detergent and in agriculture and aquaculture, for example to control pests in ponds.

Tea seed oil is used for stir-frying, deep-frying, salad dressings, dipping and finishing. It tolerates high heat better than many oils and has a light flavour. It is also used in traditional hair and skin care, in soaps and in cosmetics. The seed cake is used as a natural cleaner and fertiliser, but it is not suitable for food in its unprocessed form because of the saponins it contains.

Tea seed oil is primarily monounsaturated fat, with oleic acid forming the bulk of the fatty acids, and a smaller proportion of saturated and polyunsaturated fats. Like other oils, it is energy dense and contains no protein or carbohydrate. Small amounts of vitamin E and plant compounds are present in less refined oils. Studies have examined its fatty acid profile in comparison to olive oil, but there is limited research on health outcomes. It can be a reasonable cooking oil in a balanced diet when used in moderation.