Chinese cabbage

Chinese cabbage
Brassica rapa chinensis, called "bok choy" in the United States
Species	Brassica rapa
Cultivar group	Chinensis, Pekinensis groups
Origin	China, before the 15th Century
Cultivar group members	many, see text

Chinese cabbage (Brassica rapa, subspecies pekinensis and chinensis) can refer to two distinct varieties of Chinese leaf vegetables often used in Chinese cuisine: Pekinensis (napa cabbage) and Chinensis (bok choi).

These vegetables are both variant cultivars or subspecies of the turnip and belong to the same genus as such Western staples as cabbage, broccoli, and cauliflower. Both have many variations in name, spelling, and scientific classification—especially the bok choy (B. rapa chinensis) variety.

History

There is evidence that the turnip was domesticated in India for its oil-bearing seeds before the 15th century BCE. Unlike the European turnip, however, the cultivation of the Chinese cabbage has focused on its leaves instead of its roots.

It was principally grown in the Yangtze River Delta region, but the Ming Dynasty naturalist Li Shizhen popularized it by bringing attention to its medicinal qualities. The variant cultivated in Zhejiang around the 14th Century was brought north and the northern harvest of napa cabbage soon exceeded the southern one. These were then exported back south along the Grand Canal to Hangzhou and traded by sea as far south as Guangdong.

The Napa cabbage became a Manchurian staple for making suan cai, the Chinese sauerkraut. In Korea, this developed into kimchi. The vegetable spread to Japan following its wars in Manchuria during the Russo-Japanese War in the early 20th Century. Chinese cabbage is now commonly found in markets throughout the world, catering both to the Chinese diaspora and to northern markets who appreciate its resistance to cold.

Varieties

Green bok choy
Chinese name
Chinese	小白菜
Transcriptions Standard Mandarin Hanyu Pinyin xiǎobáicài Wu Romanization tsching tsae 青菜 Yue: Cantonese Jyutping baak9 coi5 Southern Min Hokkien POJ be̍h-chhài or pe̍h-chhài
Korean name
Hangul	청경채
Transcriptions Revised Romanization cheonggyeongchae

There are two distinctly different groups of Brassica rapa used as leaf vegetables in China, and a wide range of varieties within these two groups. The binomial name B. campestris is also used.

Pekinensis

Main article: Napa cabbage

This group is the more common of the two, especially outside Asia; names such as napa cabbage, dà báicài (Chinese: 大白菜, lit. "large white vegetable"); Baguio petsay or petsay wombok (Tagalog); Chinese white cabbage; "wong a pak" (Hokkien, Fujianese); baechu (Korean), wongbok and hakusai (Japanese: 白菜 or ハクサイ) usually refer to members of this group. Pekinensis cabbages have broad green leaves with white petioles, tightly wrapped in a cylindrical formation and usually forming a compact head. As the group name indicates, this is particularly popular in northern China around Beijing (Peking).

Chinensis

Chinensis varieties do not form heads; instead, they have smooth, dark green leaf blades forming a cluster reminiscent of mustard or celery. Chinensis varieties are popular in southern China and Southeast Asia. Being winter-hardy, they are increasingly grown in Northern Europe. This group was originally classified as its own species under the name B. chinensis by Linnaeus.

Chinensis spelling and naming variations

Other than the ambiguous term "Chinese cabbage," the most widely used name in North America for the chinensis variety is bok choy (from Cantonese, literally "white vegetable"; also spelled Pak choi, Bok choi, and Pak choy). In the UK, Australia, South Africa, and other Commonwealth Nations, the term Pak choi is used. Less commonly, the descriptive English names Chinese chard, Chinese mustard, celery mustard, and Spoon cabbage are also employed.

In Australia, the New South Wales Department of Primary Industries has redefined many of these names to refer to specific cultivars. In addition, they have introduced the word buk choy to refer to a specific kind of cabbage distinct from pak choy.

In China, three terms are commonly used for this vegetable: the majority of Chinese (about 955 million) speak Mandarin, and for them the term is 油菜 yóu cài (literally "oil vegetable"), since most of the cooking oil in China is extracted from the seed of this plant; Shanghainese speakers (about 90 million in eastern China) use the term 青菜 qīng cài (literally "blue-green vegetable"); although the term 白菜 is pronounced "baak choi" in Cantonese, the same characters are pronounced "bái cài" by Mandarin speakers and used as the name for Napa cabbage which they call as "Chinese cabbage" when speaking English.

Commercial variants of Chinensis

• Bok choi (Chinese: 白菜; lit. 'white vegetable'; [[[:ja:青梗菜|青梗菜]] or チンゲンサイ, Chingensai] Error: {{Lang-xx}}: text has italic markup (help)); succulent, white stems with dark green leaves.
• Choy sum (Chinese: 菜心; pinyin: càixīn; lit. 'vegetable heart'; Hokkien chai sim; [[[:ja:サイシン (中国野菜)|菜心]] or サイシン, Saishin] Error: {{Lang-xx}}: text has italic markup (help)), this brassica refers to a small, delicate version of Bak choi. In appearance it is more similar to rapini or broccoli rabe, than the typical Bak choi. In English, it can also be called "Flowering Chinese Cabbage" due to the yellow flowers that comes with this particular vegetable. The term "choy sum" is sometimes used to describe the stem of any Chinese cabbage, or the soft inner core of a Bak choi with the tougher outer leaves removed.
• Baby pak choi or mei quin choi, also known as Shanghai Bak choi (Chinese: 上海白菜; pinyin: Shànghǎi báicài (Cantonese: Song Hoi bak choi); [[[:ja:青梗菜|青梗菜]] or チンゲンサイ, chingensai] Error: {{Lang-xx}}: text has italic markup (help)) refers to greener varieties where the varioles are also green. It is simply a less-mature version that could develop into the white-stemmed variety with more time to grow before being harvested. In Shanghai and other eastern China provinces, it is simply called qīngcài (青菜; literally blue/green vegetable) or qīngjiāngcài (青江菜; literally "blue/green river vegetable").

Nutritional value

Chinese cabbage, raw
(chinensis, pak choi)

Nutritional value per 100 g (3.5 oz)
Energy	54 kJ (13 kcal)
Carbohydrates	2.2 g
Dietary fiber	1.0 g
Fat	0.2 g
Protein	1.5 g
Vitamins and minerals Vitamins Quantity %DV† Vitamin A equiv. 27% 243 μg Vitamin A 4468 IU Vitamin C 50% 45 mg Minerals Quantity %DV† Calcium 8% 105 mg Iron 4% 0.80 mg Magnesium 5% 19 mg Sodium 3% 65 mg
†Percentages estimated using US recommendations for adults, except for potassium, which is estimated based on expert recommendation from the National Academies.

Pak choi contains a high amount of vitamin A per 4 oz. of serving - about 3500 IU. Pak choi also contains approximately 50 mg of vitamin C per 4 oz. serving.

Toxic effects

Pak choi contains glucosinolates. These compounds have been reported to prevent cancer in small doses, but, like many substances, can be toxic to humans in large doses, particularly to people who are already seriously ill. In 2009, an elderly diabetic woman who had been consuming 1 to 1.5 kg of raw Pak choi per day, in an attempt to treat her diabetes, developed hypothyroidism, for reasons relating to her diabetes, resulting in myxedema coma.

Gallery

• B. rapa chinesis's yellow flowers
  B. rapa chinesis's yellow flowers
• B. rapa chinesis
  B. rapa chinesis
• 
  Cooked bok choy

See also

• Turnip, the same species B. rapa cultivated in Europe for its roots
• Cabbage, the related European vegetable B. oleracea (Capitata)
• Chinese broccoli (芥兰, p gàilán), the Chinese vegetable B. oleracea alboglabra ("kai-lan")
• Snow cabbage (雪菜, p xuěcài), the related Chinese vegetable B. juncea
• Rapeseed (油菜, p yóucài), the related B. napus consumed in China as a vegetable ("yu choy")

External links

• Nutritional information on bok choy (with photo of chinensis variety)
• Multilingual taxonomical information from the University of Melbourne
• How to choose, store and use pak choi from Veg Box Recipes