Lightly smoky and full of umami, Mentsuyu is a Japanese soup base used in a multitude of noodle dishes. You can easily make it at home with sake, mirin, soy sauce, and katsuobushi (dried bonito flakes).
Mentsuyu (めんつゆ), or sometimes called Tsuyu (つゆ), is a Japanese soup base commonly used in soba and udon noodle dishes. Made from sake, mirin, soy sauce, kombu, and katsuobushi (dried bonito flakes), the flavor is delicate yet intensely savory.
Table of Contents
What is Mentsuyu (Tsuyu) for?
In Japan, we use Mentsuyu as a basic sauce or broth to flavor everything from noodle dishes, rice bowls, and hot pots to the tempura dipping sauce.
The multipurpose sauce gets a real depth of flavor and smokiness from the use of kombu and bonito flakes. As it happens, these two ingredients are the elementary components to make dashi—the Japanese soup stock that characterize the distinct flavor of Japanese food.
In this recipe, soy sauce contributes to the savory tones, and mirin imparts sweetness that ties everything together.
Making Mentsuyu at home is as easy as combining all the ingredients in a pot and letting it simmer down to a concentrated sauce. You can store it in a mason jar and keep it in the refrigerator for up to a month. The sauce will come in handy when you need it to season your favorite noodle dishes.
When ready to use, you just need to thin it out with water! The ratios of Mentsuyu to water will differ depending on the recipes.
Use Mentsuyu for Hot Noodle Soup
To use Mentsuyu in a hot noodle soup, dilute it with water, heat it up, then pour over boiled noodles. This hot noodle soup broth is called Kaketsuyu (かけつゆ).
Use Mentsuyu for Cold Noodle Dipping Sauce
The Mentsuyu is diluted with water (sometimes no need to dilute), then serve with chilled noodles. This dipping sauce is called Tsuketsuyu (つけつゆ).
Convenient Store-Bought Mentsuyu Bottles
For convenience, you can purchase pre-made Mentsuyu from Japanese (or Asian) grocery stores or online.
Each brand has different instructions for diluting the Metsuyu. Find the usage guide on the bottle that looks like this. You can learn more about the Ratio of Tsuyu to Water on this page.
Use Mentsuyu in These Recipes!
- Cold Tanuki Udon
- Zaru Soba
- Yaki Udon
- Mushroom and Tuna Japanese Style Pasta
- Hiyayakko (Japanese Cold Tofu)
- Kitsune Udon
- Negitoro & Avocado Donburi
Wish to learn more about Japanese cooking? Sign up for our free newsletter to receive cooking tips & recipe updates! And stay in touch with me on Facebook, Pinterest, YouTube, and Instagram.
Homemade Mentsuyu (Japanese Noodle Soup Base)
- ½ cup sake
- 1⅛ cup mirin
- 1 cup soy sauce
- 1 piece kombu (dried kelp) (5 g; 2 inches x 2 inches or 5 x 5 cm)
- 1 cup katsuobushi (dried bonito flakes) (for vegetarian/vegan, omit or substitute it with 2 dried shiitake mushrooms)
- Gather all the ingredients.
- In a saucepan, add the sake, mirin, and soy sauce.
- Add kombu and katsuobushi.
- Slowly bring it to a boil over medium-low heat.
- Then, reduce the heat to low and simmer for 5 minutes. Then turn off the heat and let it cool.
- Pass the mixture through a fine-mesh sieve (reserve the kombu and katsuobushi for another use—see below).
To Use the Mentsuyu
- This Mentsuyu is concentrated. In general, the mentsuyu-to-water ratio should be 1:2 for a dipping sauce for Zaru Soba/Udon, and 1:4 for Udon/Soba Noodle Soup. Please adjust the taste of your dipping sauce or soup broth by adding more mentsuyu or water.
- You can store the Mentsuyu in a mason jar in the refrigerator for up to a month.
What to do with the spent katsuobushi and kombu?
- Save the spent kombu and katsuobushi in an airtight container and store it in the refrigerator for a week or in the freezer for up to a month.
- Repurpose the spent katsuobushi and kombu to make Homemade Furikake (Rice Seasoning).
Editor’s Note: This post was originally published on July 16, 2013. It’s been republished on May 5, 2022, with updated step-by-step and final images.