Saishin / cai xin / yu choy sum

Brassica parachinensis

Sometimes called “flowering cabbage,” the yu choy sum on store shelves often has yellow flowers in the center. Unlike cabbage, yu choy sum’s leaves (and stems) are tender, darker green, and are always cooked rather than eaten raw, as far as I know. As with many other Chinese vegetables, there seem to be endless variations of the name, including yu choy, choy sum and choy sim. No matter how it is called, this vegetable is known for excellent nutrition. Carotene, iron, potassium, calcium, Vitamins B and C, folic acid and niacin are the nutrients often mentioned for yu choy sum. What all these nutrients can bring is beautiful, radiant skin; they also reduce active oxygen and control cancer cell proliferation, increase immune strength, prevent colds, control high blood pressure, and strengthen bones, teeth and nails, and so on. While the nutritional data I’ve found is sketchy on details, let's just say it is a valuable vegetable full of health benefits.

Yu choy sum's thick stems and large leaves both taste mild and cook fast.  Stems stay relatively crispy when cooked and do not get soggy in soup. Among Chinese leafy greens introduced in Japan in the last decade or two, yu choy sum is probably the most adaptable for Japanese cooking, more so than chingensai baby bok choy. Yu choy sum is very similar to nanohana field mustard and komatsuna.

21 kcal/100 g; 93.5% water, 2.2% protein, 0.7% fat, 1.7% carbohydrate, 1.1% ash (not confirmed; data varies by source)

Recipes with saishin yu choy sum

• Gomoku ankake udon / wheat noodles with thickened soup and assorted ingredients
• Tonyu miso nikomi udon / hot-pot udon wheat noodles in red miso and soy milk broth 
• Koyadofu to saishin no nibitashi / freeze-dried tofu and yu choy sum simmered in broth
• Saishin no karashi oisutaasoosu-ae / yu choy sum in Japanese mustard and oyster sauce dressing
  
• Ebi to kobashira no gorugonzoora soosu guratan / shrimp and bay scallop gratin with gorgonzola cheese
  
• Sake to hijiki no itameni / salmon saute with hijiki seaweed
  
• Atsuage, moyashi, saishin no nibitashi / deep-fried tofu, mung bean sprouts and yu choy sum simmered in light broth 
• Tonyu nabe / hot pot with soy milk broth
  
• Kiriboshi-daikon to saishin no misoshiru / miso soup with dried julienned daikon radish and yu choy sum
• Sakana to saishin no tamagoyaki / omelet with fish and yu choy sum 
• Kani no iimushi / steamed sweet rice and crab with light soy-sauce flavored dashi sauce
• Karei no nitsuke / sole simmered in reduced broth
  
• Saishin to kani, shiitake, tamago no itamemono / yu choy sum, crabmeat, shiitake mushrooms and egg saute
  
• Karifurawaa to saishin no hana no misoshiru / miso soup with cauliflower and yu choy sum blossoms

Try saishin yu choy sum in the following recipes

• Koyadofu no ageyaki to renkon no horenso-an / fried freeze-dried tofu and lotus root with spinach dashi sauce
  
• Miso yasai raamen / vegetable ramen noodles with miso-flavored soup
• Tosho chaamen / dao xiao chao mian / fried hand-shaven noodles
• Okara tamago karee-aji to horenso, komatsuna no bataa-joyu itame / stir-fried spinach, komatsuna and egg with soybean pulp and curry, soy sauce butter flavor 
  
• Suigyoza no chige-fu nabe / jjigae-style hotpot with shui jiao dumplings
  
• Horenso to shungiku, kikka no ohitashi / spinach, garland chrysanthemum and chrysanthemum flowers in light broth
  
• Shungiku to ringo no mizore-ae / garland chrysanthemum and apple with grated daikon radish and sweetened vinegar 
• Nori to nanohana no osuimono / clear soup with nori seaweed and field mustard flowers
  
• Kankoku mitsuba no shiraae / cham namul with tofu dressing
  
• Kaisen chukadon / Chinese-style seafood saute over steamed rice 
• Asari no sakamushi / steamed clams with sake
• Sakana no oisutaasoosu-ni, howajao-iri / simmered fish in oyster sauce-flavored broth with Sichuan peppers
• Ebi-shinjo to yasai ribon no nabe / hot pot with prawn-fish dumplings and vegetable ribbons
  
• Kani zosui / steamed rice with crab and egg in broth
  
• Kabu no ha to ninjin, age no nibitashi / Japanese turnip leaf, carrot and thin deep-fried tofu in light broth
  
• Atsuage to chingensai no kurozuan itame / deep-fried tofu and baby bok choy saute with thickened brown rice vinegar sauce
  
• Yosenabe / hot pot with assorted ingredients
• Chirimushi / steamed fish, tofu, vegetables and mushrooms, with citrus-flavored soy sauce
• Ninjin to horenso no shiraae / carrot and spinach in tofu dressing
• Chuukadon / Chinese-style saute with sauce over steamed rice 
• Harusame to komatsuna no itameni / saute-simmered mung bean vermicelli and komatsuna 
• Nanohana no namuru / field mustard namul (gochujang flavor)
• Tororo to kabu no hana no osumashi / clear soup with grated Chinese yam and Japanese turnip flowers
  
• Sakana to tofu, kimuchi no sattoni / quick-simmered fish, tofu and kimchi
• Yasai chuka yakisoba / Chinese stir-fried noodles with vegetables
• Gyoza no pirikara-nabe / mildly spicy hot pot with jiaozi dumplings and kimchi 
• Sakana to yasai no sotee gaarikku remon soosu / fish and vegetable saute with garlic lemon sauce
• Atsuage to komatsuna no champuruu / Okinawan-style stir-fry with deep-fried tofu and komatsuna
• Komatsuna to atsuage no miso-itame / sauteed komatsuna and deep-fried tofu with miso sauce
• Hotate to komatsuna no karamiae / scallops and komatsuna in spicy sauce
• Komatsuna to usuage no nibitashi / komatsuna and thin deep-fried tofu in broth
• Ebi ankake yakisoba / fried noodles with prawns and vegetables sauce

(Last updated: April 27, 2019)