Lotus seeds or Lotus nuts are the seeds of plants in the genus Nelumbo, particularly the species Nelumbo nucifera. The seeds are of great importance to East Asian cuisine and are used extensively in traditional Chinese medicine and in Chinese desserts. The seeds are most commonly sold in the shelled and dried form. Fresh lotus seeds are relatively uncommon in the market except in areas of lotus root and seed production, where they are sometimes sold as a raw snack.
Two types of dried lotus seeds can be found commercially; brown peel and white. The former is harvested when the seed head of the lotus is ripe or nearly ripe and the latter is harvested when the seed head is still fully green, but with almost fully developed seeds. White lotus seeds are de-shelled and de-membraned. The bitter tasting germ of the seed is also removed at the time of harvest using a hollow needle, though some may still remain in the seed due to production oversight. Brown peel lotus seeds are brown because the ripened seed has adhered to its membrane. These seeds are usually cracked in half in order to remove the germ since the seeds are hard enough to make the germs' removal by needle difficult.
Dried lotus seeds past their prime oxidize to a yellow brown colour. However, this is not necessarily an indicator of freshness since sellers of dried lotus seeds may choose to bleach their products with hydrogen peroxide, sodium hydroxide, or other more toxic chemicals(in Chinese).
Dried lotus seeds as they are commonly found in the market
Traditional Chinese: 蓮子
Simplified Chinese: 莲子
Hanyu Pinyin: lián zǐ
Cantonese Jyutping: lin4 zi2
Literal meaning: lotus seed
Dried lotus seeds that are sold in packages or in bulk at many Asian markets must first be soaked in water overnight prior to use due to their hardness and toughness. They can then be added directly to soups and congee, or used in other dishes.
Fresh lotus seeds are sold in the seed heads of the plant and eaten by breaking the individual seeds out of cone shaped head. The soft rubbery shell that surrounds each seed should be removed before consuming.
Crystallized lotus seeds (蓮子糖), made by drying lotus seeds cooked in syrup, are a well-loved Chinese snack and are eaten especially near Chinese new year.
The most common use of the seed is in the form of lotus seed paste (蓮蓉), which is used extensively in Chinese pastries. The paste is also used in Japanese cuisine, as an ingredient in cakes and other dessert items.
Eating fresh lotus seeds from a lotus (Nelumbo) seed head
Chinese medicinal foods
When cooked in clear soups, lotus seeds are believed in Chinese medicine to "clear heat" (清熱) and be particularly nutritious and restorative to one's health, which may explain the prevalence of their use in Chinese cuisine.
Other ingredients that are considered "cooling" or restorative in Chinese medicines, which are often cooked in a sweetened soup with lotus seeds include:
Azuki beans (紅豆)
Job's tears (薏仁)
Dried jujubes (紅棗)
Mung beans (绿豆)
Asian pear (雪梨)
Snow fungus (银耳 or 白木耳)
Lotus soups sometimes also include a whole chicken, other poultry, or fish for similar medicinal purposes.
The bitter dried germ of the lotus seed can also be found sold as a restorative tisane (蓮子心茶).