Chinese mustard originated in the Foothills of the Himalayas. They harvest in early summer through late autumn. Chinese mustard is also known as gai choy and is a species of mustard plant that has been cultivated long ago for its leaves and seeds. A subvariety is southern giant curled mustard which is like kale, but has a horseradish flavor. The leaves are widely used in Asian cooking and can be cooked like spinach. The seeds of Chinese mustard are some of the smallest seeds, about 1/8 inch in diameter and vary in color from yellow to white to brown or black. These seeds and oil extract from the seeds are very important in many regional Indian and Bangladeshi cuisines. In one cup of cooked chinese mustard there are 21 calories, 3.2 grams of protein, 2.9 grams of carbohydrate and 2.8 grams of fiber. In this cup, there is five times the Daily Value of vitamin K and is high in vitamins A, C and folate. Chinese mustard is also an excellent source of manganese, potassium, copper, and calcium. It is also a good source of fiber and provides a high level of antioxidants, including beta-carotene, lutein, and zeaxanthin.
Chinese mustard greens add a pungent flavor to a salad when mixed with milder greens like kale, cabbage, or collard greens. It does not require additional flavoring. Adding 6 cups of the stems to hot olive oil and sauteing in garlic can add extra nutrients.
The high antioxidant content in Chinese mustard may help prevent diseases where oxidative damage plays a role. In a large study in 2007, it was shown that higher intakes of this vegetable can be linked to lower risks of prostate cancer.
Source: Reinhard, Tonia. Superfoods: the Healthiest Foods on the Planet. Buffalo, NY: Firefly, 2010. Print.