Stocks & broths
Mentsuyu
めんつゆ · Mentsuyu is a foundational Japanese liquid seasoning — a concentrate of dashi (kombu and katsuobushi stock) combined with kaeshi (a reduction of soy sauce, mirin, and sake) — used as a reusable base to season noodle soups, dipping sauces, hot pots, simmered dishes, and rice bowls. It is not consumed on its own but diluted or applied as a building block for finished dishes.
The formula
concentrate: kaeshi : dashi ≈ 1 : 1; dip ≈ 1 : 1; kaketsuyu (soup) ≈ 1 : 3 to 1 : 9 with water/dashi
Concentrate is built from equal parts soy, mirin, and sake (kaeshi) joined with roughly equal-volume dashi. The same concentrate is used undiluted (or barely diluted) for tsuketsuyu dipping sauces, and pulled thin with water or extra dashi for kaketsuyu hot broths.
Identity
- A reusable base, not a finished dish
- Built from two named Japanese foundations: dashi (umami stock) and kaeshi (sweet-savory seasoning reduction)
- Salt- and umami-balanced, with restrained sweetness from mirin
- Naturally clear, amber, and glossy once simmered
- Stores for weeks refrigerated and freezes well, suiting batch prep
- Doubles as seasoning, dipping sauce, and hot broth depending on dilution
Ingredients
| Base | Dashi (kombu + katsuobushi, ichiban-dashi) | Provides the umami backbone; ratio to kaeshi controls the final intensity. |
| Seasoning | Koikuchi soy sauce | The salt and color axis of the kaeshi side. |
| Sweetener | Mirin | Brings gentle sweetness and gloss; should be hon-mirin or at least aji-mirin. |
| Liquid | Sake | Adds roundness, masks fishy edges, and is boiled off (nikiri) for clean flavor. |
| Flavor | Katsuobushi (optional finishing steep) | A second small charge steeped into the warm concentrate intensifies smoky bonito notes; not required if the dashi is already richly built. |
| Sweetener | Sugar (optional) | Some kaeshi versions add a touch of sugar for balance; many skip it because mirin supplies enough sweetness. |
Method
- 1Combine mirin and sake in a saucepan; bring to a gentle boil and hold 2 minutes to evaporate raw alcohol (nikiri).Boiling off alcohol prevents a harsh, flat edge in the finished concentrate and lets the mirin's sweetness come forward.
- 2Add soy sauce and dashi; bring to a gentle simmer — small bubbles at the edge, not a rolling boil.A hard boil drives off aroma, muddies the clarity, and can make the soy sauce taste bitter.
- 3Simmer uncovered 8–10 minutes until the liquid reduces slightly and turns a glossy, deep amber.Concentration deepens flavor and gives the surface sheen characteristic of a finished mentsuyu.
- 4Off heat, optionally add a small handful of katsuobushi and let steep 2–3 minutes, then strain.A finishing steep of bonito after heat-off layers smoky umami on top without clouding the sauce.
- 5Cool, bottle, and refrigerate; dilute at service as needed (1:1 for dip, 1:3–1:9 with water or dashi for soup).Concentrate keeps longer and lets the cook tune salt/umami strength per dish.
Techniques that matter
Nikiri (alcohol burn-off)
Removes raw alcoholic harshness from mirin and sake so only the rounded sweetness and body remain.
Ratio control via dilution
A single concentrate flexes between dipping sauce (nearly straight) and soup (heavily pulled with water), which is what makes mentsuyu a true reusable base.
Variations & derivatives
Kaketsuyu (hot noodle broth)Japan (home & restaurant)
Mentsuyu thinned with hot water or extra dashi, typically 1:3 to 1:9 depending on desired strength, poured over udon or soba.
Tsuketsuyu / Zaru-mentsuyu (cold dipping sauce)Japan (summer service)
Mentsuyu used straight or lightly diluted, served cold with chilled soba or somen; sometimes spiked with wasabi, grated daikon, or scallions.
Tentsuyu (tempura dipping sauce)Japan
Mentsuyu diluted with dashi and sometimes mirin, served warm in a shallow bowl alongside grated daikon for tempura.
Nimono-tsuyuJapan
A milder, slightly sweeter mentsuyu used as the braising liquid for simmered dishes and oden.
Hiyayakko / agedashi dressingJapan
Mentsuyu diluted and spooned over cold tofu or used as the broth for agedashi tofu.
Used in these dishes
Substitutions
- Hon-mirin → Aji-mirin — Aji-mirin works but is sweeter and lower in alcohol; reduce added sugar if used.
- Sake → Dry white wine (small amount) — Removes alcohol harshness similarly but slightly changes aroma; safe in a pinch.
- Kombu-katsuobushi dashi → Shiitake dashi or kombu-only dashi — Vegetarian; result is lighter and less smoky, so the concentrate reads more savory than brisk.
- Katsuobushi → Niboshi (dried baby sardines) — Adds a different, more briny umami; classic in some regional styles.
- Soy sauce → Tamari — Gluten-free option; slightly rounder and less sharp.
Troubleshooting
Sauce tastes harsh or alcoholic
Mirin/sake not simmered long enough to boil off alcohol (skipped nikiri step). → Return to a gentle boil and reduce 2–3 minutes, or dilute with a splash of dashi.
Sauce is too salty
Concentrate is meant to be diluted; used straight where dilution was expected. → Pull with water or unsalted dashi; for soup use the 1:3–1:9 range, taste as you go.
Muddy, cloudy appearance
Rolled the boil, or added katsuobushi during a hard simmer. → Strain through a fine sieve or coffee filter; next time keep to a gentle simmer and steep katsuobushi off heat.
Flat, one-dimensional flavor
Dashi was weak (under-extracted kombu/katsuobushi) or kaeshi was under-developed. → Rebuild dashi with a proper 1-hour kombu steep and 10-minute bonito steep, then re-blend the concentrate.