Yuzu: What It Is, Flavor, Juice, Yuzu Kosho and Substitutes

Appearance and flavor

A yuzu is about the size of a mandarin. The peel is thick, wrinkled and yellow; unripe fruits are green. Inside are many large seeds and little flesh, and one fruit gives only one to two tablespoons of juice. Press it through a strainer to hold back the seeds.

The juice tastes strongly sour and less bitter than grapefruit. The typical fragrance comes from the peel: floral, fresh, somewhere between lemon, mandarin and grapefruit. The aroma fades fast when cooked. So add yuzu only at the end or to cold dishes. Yuzu itself is not among the major allergens; for ready-made products such as ponzu, though, check the ingredient list for soy, wheat and fish.

Origin

Yuzu (柚子, botanically Citrus junos) originally comes from China. Today mainly Japan and Korea grow it; in Korea it is called yuja (유자). The tree tolerates more cold than most citrus plants. In Japan farmers harvest green yuzu from late summer, ripe yellow fruits in autumn and winter. Hardly anyone there eats the fruit raw. At the winter solstice many families put whole yuzu in the hot bathwater; the custom is called yuzuyu.

Uses

• Juice: It makes Ponzu the classic dipping sauce for Shabu shabu, gyoza and grilled fish. You can read more about the sauce under Ponzu. It also seasons dressings, marinades and desserts.
• Zest: Hair-thin strips or a hint of grated zest give clear soups, nabe dishes and Sashimi a fragrance.
• Yuzu kosho: a seasoning paste of chili, yuzu zest and salt that ripens for some time. Producers make green yuzu kosho from green chili and unripe zest, red from red chili and ripe zest. The paste is salty and hot; a knife tip is enough for grilled food, Karaage or a Yuzu kosho dip.
• Yuja-cha: In Korea families cook the whole fruit in slices with sugar or honey into a kind of marmalade. Steeped in hot water it becomes Yuja-cha, a winter drink.
• Sweets and drinks: Yuzu juice suits sorbet, cheesecake, lemonade and cocktails. A few drops are enough; the fragrance is strong.

Buying yuzu

Fresh yuzu are rare outside Japan and Korea. In winter some specialty food shops, Asian grocery stores with a Japanese range and online retailers offer them, often at high prices. Yuzu products are easier to get:

• Bottled yuzu juice: Read the label. Some juices contain salt as a preservative, others are mixed with lemon or other citrus juice. For dressings and ponzu, use pure juice without salt.
• Yuzu kosho in a jar or tube, at an Asian grocery store with a Japanese range and online.
• Yuja-cha in a jar, at Korean grocery stores.
• Ready-made yuzu ponzu, handy if you need the juice only for ponzu.
• Frozen zest or juice from specialized online retailers.

Substitutes for yuzu

No other fruit matches the fragrance of yuzu. With a mix you can come close:

• Juice: Mix 2 parts lemon juice, 1 part lime juice and 1 part mandarin or grapefruit juice. Replaces yuzu juice 1 : 1. For ponzu, half lemon and half orange juice also works.
• Zest: Finely grate lemon and mandarin zest in equal parts.
• Yuzu kosho: Grind one finely chopped green chili with the zest of an organic lemon or lime and a generous pinch of salt.
• Related fruits: Sudachi and kabosu are Japanese citrus fruits that cooks use in a similar way. One example is Sudachi ponzu.

The page Substituting Asian ingredients collects more mixes for mirin, rice vinegar and the like.

Storage

Fresh yuzu keep one to two weeks in the vegetable drawer of the refrigerator. To use them longer, grate the zest and freeze it in small portions; freeze the juice in an ice cube tray. Keep opened yuzu juice in the refrigerator and use it within the period on the bottle; the aroma fades after a few weeks. Yuzu kosho keeps for several months refrigerated, and an opened jar of yuja-cha does too.