Korean Thistle

Health Benefits

What the Donguibogam records — nature, taste and gathering time. The Donguibogam lists the plant in the Herb section as 大薊. It gives a neutral nature, a bitter taste and no toxicity, and notes that it grows everywhere. For gathering it records shoots and leaves in the fifth lunar month and roots in the ninth, dried in the shade, and gives 刺薊 as an alternative name. This is a historical medical record and differs from modern medical judgment.

The record that separates 大薊 from 小薊. The same entry sets 大薊 and 小薊 side by side and tells them apart by form. 大薊 stands three or four cheok tall with wrinkled leaves, while 小薊 reaches about one cheok and its leaves are not wrinkled. 小薊 is glossed in Korean as jobangga, corresponding to today's jobaengi. The entry also explains that 地丁 is 大薊, the yellow-flowered kind called 黃花地丁 and the purple-flowered kind 紫花地丁. In present-day usage, however, 黃花地丁 names the dandelion and 紫花地丁 the violet, both of them plants other than thistle. This is a historical medical record and differs from modern medical judgment.

Pectolinarin analysis. Compositional studies of Cirsium species report pectolinarin and pectolinarigenin as the principal flavonoids, with wide variation in content according to plant part and gathering date. These are compositional analyses and have nothing to do with preventing or treating disease.

Nutrition

• Pectolinarin (reported from leaf and flower) — a flavonoid characteristically identified in Cirsium species
• Luteolin and apigenin glycosides (leaves) — flavonoids common across the daisy family
• Inulin (the thick root) — the storage polysaccharide of daisy-family roots
• Dietary fibre (stems and leaf veins) — the fibre that makes the tissue tough

Young leaves and bitterness The young spring leaves are bitter and their veins are tough. Blanch them in salted boiling water, then soak for about half an hour in cold water and the bitterness eases. Long blanching strips the flavour out entirely, so lift them as soon as the colour deepens. Spines soften in the water, but on coarser leaves it is better to strip the margins first.

Flavonoid profile Pectolinarin and its aglycone pectolinarigenin are frequently reported from Cirsium species. Luteolin- and apigenin-type glycosides are identified alongside them. Analyses note that content varies widely by plant part and gathering date. This entry stays with the compositional record.

Root and inulin Many daisy-family perennials store inulin rather than starch in the root, and thistle is one of them. Human digestive enzymes cannot break inulin down, so it reaches the large intestine intact and gut bacteria ferment it. A first helping of root can bring on gas, so build the amount up slowly.

Look-alikes and how to tell them apart Jobaengi, which grows on the same ground, has small leaves whose margins are not wrinkled and far weaker spines, setting it apart from the large, deeply cut leaves of Korean thistle. What is sold as seed or seedling under the name 'milk thistle' is the Mediterranean Silybum marianum, distinguished by the bold white marbling that runs along its veins. The compound name 'silymarin' belongs to that plant too, and differs from what is reported in the thistles of Korean fields and hillsides. A shared word in the common name does not make it the same plant, so check the botanical name and the origin before buying.

Pairings

○ Doenjang and perilla — Blanched young leaves dressed with doenjang and perilla oil carry the bitterness well. Simmering them into a soup with ground perilla seed is just as common. Keep garlic light so the leaf flavour survives. Perilla (Deulkkae)

○ Doenjang soup with rice-rinse water — Stir doenjang into the water left from rinsing rice and add the blanched leaves; the broth stays clean rather than heavy. The longer it boils the softer the leaves go and the more bitterness leaches out, so add them near the end. Reheat only the portion you plan to eat that day.

○ Dried as mukna-mul — If the picking has been generous, blanch the surplus and dry it. Dried leaves are rehydrated, boiled and stir-fried through the winter. Gondre, the dried form of Cirsium setidens, is prepared the same way.

△ Not every spiny rosette is a thistle — In the spring rosette stage, Hemistepta lyrata (jichingae) and small thistle (jobaengi) grow mixed in with Korean thistle. Both are eaten in places, but their flavour and blanching times differ, so gathering them together spoils the dish. The one to watch harder is horsenettle (Solanum carolinense), an invasive species listed in Korea: it carries spines on leaves and stems, so choosing by spines alone can pick it up, and its nightshade alkaloids make it unfit to eat. The safest rule is to gather only where you saw the plant in flower the previous year.

△ Never gather from verges or field margins — Thistle thrives exactly where herbicide drift and road dust land — roadsides and the edges of cultivated fields. Washing does not remove either. If there is no clean ground to gather from, save seed and grow a few plants in a border or a large pot instead.

△ Daisy-family allergy — Thistle belongs to the daisy family. People who react to mugwort or ragweed pollen sometimes get an itchy mouth or hives from daisy-family greens as well. Start with a mouthful or two, and stop and seek medical advice at once if the lips swell or the throat feels tight.

Varieties

• Korean thistle (seed) — Pronounced leaf spines and purple flowers. The native species this entry describes
• Gondre (Cirsium setidens) (seed) — Weak spines and broader leaves. Widely grown as a vegetable
• Small thistle, jobaengi (小薊) (seed) — Only about a foot tall. The plant the old text sets apart from 大薊
• Milk thistle (seed) — A Mediterranean plant of a different genus with white-marbled leaves. Not the same plant as Korean thistle