Coriander Root Tea: Turning Leftover Cilantro Roots into a Fragrant Infusion

Coriander root tea is a simple infusion made by simmering cleaned, lightly crushed coriander (cilantro) roots in water and then straining out the solids. It brews to a pale straw or light golden liquid. It smells earthy and peppery, with a soft citrus edge, and tastes deeper and less grassy than the leaves. It is not a classic Thai drink in the way lemongrass or pandan drinks are. It is a thrifty way to use the roots that Thai cooks prize, and that many shoppers simply throw away.

What are coriander roots, and how do you recognize them?

Coriander roots are the pale taproots at the base of a fresh coriander plant, the part below where the stems meet. In Thai they are called rak phak chi. They are usually a few centimeters long and about as thick as a matchstick or a thin pencil. Their color ranges from creamy white to light tan, and fine, hair-like rootlets branch off the sides. When fresh, they feel firm and slightly springy rather than limp.

The quickest test is your nose. Snap or scratch a root and you get a concentrated coriander smell: earthy, a little peppery, with a citrusy lift. It is more intense and musky than the bright, green scent of the leaves.

Bunches with roots attached are common in Asian grocery stores and farmers' markets. Many Western supermarkets trim them off, so if you want cilantro roots, look for bunches that still have soil clinging to the base.

How are coriander roots used in Thai cooking?

In Thai kitchens, coriander roots are a flavor base. Cooks usually pound them into a paste rather than eating them whole. Their earthy depth survives long cooking and grilling, which makes them useful where the delicate leaves would wilt and fade.

• The garlic, pepper and root trio: Coriander root, garlic and white peppercorns are often pounded together in a stone mortar and pestle. This rough, fragrant paste seasons many marinades and stir-fries.
• Marinades for grilled meats: Street-food favorites such as grilled chicken (gai yang) and grilled pork skewers (moo ping) are commonly marinated with pounded coriander root.
• Curry pastes: Green curry paste and other pastes often include coriander root alongside chilies, lemongrass, galangal and shallots.
• Clear soups and broths: Cooks drop whole or bruised roots into mild clear soups (kaeng jued) to give the broth a quiet, savory background. A root tea works on the same principle, just without the meat and salt.

The mortar and pestle matters here. Pounding crushes the fibers and releases aromatic oils better than chopping alone, and a light bash before brewing tea does the same job.

How do coriander roots differ from the leaves, stems and seeds?

Each part of the coriander plant tastes different. The roots are the most earthy and the most heat-tolerant of the fresh parts. The table compares the parts you are most likely to meet in a kitchen.

Part	Appearance	Aroma and flavor	Typical Thai use	In tea
Roots	Pale cream to tan, thin, with hair-like rootlets	Earthy, peppery, concentrated coriander, softly citrusy	Pounded into pastes and marinades; simmered in broths	Main ingredient; holds flavor through simmering
Stems	Green, slender, juicy	Fresh and green, milder than roots	Chopped into pastes, salads and garnishes	Usable but lighter and grassier
Leaves	Flat, bright green, lacy edges	Bright, herbal; some people taste it as soapy	Fresh garnish on soups, salads, noodles	Fades quickly with heat; best added at the end, if at all
Seeds (dried)	Small, round, beige-brown balls	Warm, toasty, orange-peel-like	Toasted and ground into some curry pastes	Makes a different drink, spicy-warm rather than earthy

How do you make coriander root tea?

To make coriander root tea, scrub the roots well, crush them lightly, simmer them in water, then strain. The steps below give a starting point. Root size varies a lot from bunch to bunch, so adjust by taste rather than by exact weight.

What you need

• Roots from roughly 2–3 bunches of coriander. A smaller handful gives a lighter tea.
• About 500 ml (2 cups) of water
• A small saucepan
• A pestle, or the flat side of a heavy knife
• A fine-mesh sieve, plus a paper coffee filter or cloth if your roots were gritty
• Optional: a sweetener such as honey or palm sugar

Steps

1. Trim: Cut the roots off where they join the stems. Keep the stems and leaves for cooking.
2. Soak and scrub: Soak the roots in a bowl of cold water for a few minutes to loosen soil. Then rub them between your fingers or with a soft brush, paying attention to the rootlets, where grit hides. Change the water and repeat until no sand settles at the bottom.
3. Bruise: Tap the roots with a pestle or press them under a flat knife blade until they split and release their smell. Do not pound them to a paste, or straining becomes harder.
4. Simmer: Put the roots and water in the saucepan, bring to a boil, then lower to a gentle simmer. Simmer for about 10–15 minutes, until the water turns pale gold and smells clearly of coriander.
5. Steep: Turn off the heat and let the pan stand for a few more minutes for a fuller flavor.
6. Strain: Pour the tea through a fine-mesh sieve. If you see cloudiness or specks of soil, strain again through a paper filter or clean cloth.
7. Taste and adjust: Sweeten lightly if you like. If the tea tastes too strong or slightly bitter, dilute it with hot water. Next time, use fewer roots or a shorter simmer.

What the finished tea should look and taste like

A good coriander root tea is clear and light gold, with no grit at the bottom of the cup. The first sip is earthy and gently peppery, followed by a faint citrus note. A muddy or brown color usually means the roots were not washed well enough. A harsh taste usually means they were simmered too long or used in too large a quantity.

What can you add to coriander root tea?

Coriander root tea pairs well with other Thai aromatics, which add brightness or sweetness to its earthy base. Add one or two at a time so the root flavor stays noticeable.

• Lemongrass: These pale green, woody stalks smell lemony and floral. Bruise a stalk and simmer it with the roots for a brighter, more citrusy tea.
• Ginger: A few thin slices add warmth and a gentle bite.
• Pandan leaf: These long, glossy green leaves smell sweet, a little like vanilla and fresh rice. Tie one leaf in a knot and simmer it briefly for a rounder, softer aroma.
• Makrut lime leaf: These glossy, double-lobed leaves have a sharp, perfumed citrus smell. One torn leaf is enough, because they quickly overpower the roots.
• Palm sugar: This tan to caramel-colored sugar, often sold in soft discs, tastes of butterscotch. It suits the earthy roots better than plain white sugar.

Can you use substitutes if you have no coriander roots?

No ingredient tastes quite like coriander root, but a few options come close in some ways. Each one changes the tea.

• Coriander stems: The closest easy swap. The tea will be greener, lighter and less earthy, so use a larger amount and a shorter simmer.
• Coriander seeds: Lightly crushed seeds make a warm, orange-peel-scented infusion. It is pleasant, but it is a different drink and lacks the roots' earthy depth.
• Frozen roots: Not a substitute so much as a way to always have roots on hand. Wash and dry roots from each bunch you buy, then freeze them in a bag until you have enough for a pot of tea.

How should you store coriander roots and the tea?

Fresh coriander roots keep best wrapped loosely in a damp paper towel in the refrigerator. Brewed coriander root tea should be cooled, covered and refrigerated. Like any homemade herbal infusion without preservatives, the tea is best drunk within a day or two. You can serve it warm or chilled over ice, perhaps with a squeeze of lime.

One caution: people allergic to coriander or other plants in the same family should avoid the tea. Some people who find cilantro leaves soapy also notice a hint of that taste in the roots, so start with a weak brew if you are unsure.