Kuzuyu: A Pale Liquid That Turns Translucent and Thick
Combine all three ingredients before the heat goes on. Then stir constantly over high heat until the liquid is both translucent and thick.
At first, the liquid in the small saucepan is pale and cloudy. As it is stirred over the heat, it loses that cloudiness and gains body. That change is the whole point of kuzuyu (葛湯), a hot Japanese drink thickened with kudzu powder.
This article follows one specific version: the single-serving saucepan recipe published by Tengyokudo (天極堂), a Japanese kudzu specialist. It uses Yoshino hon-kuzu powder, sugar and water. It is one maker's basic recipe, not the standard for every region or brand in Japan. Tengyokudo lists only "sugar", so choosing white sugar is our own editorial decision.
We have not kitchen-tested this recipe. Tengyokudo gives no cooking time, saucepan size or finished temperature, and we have not added any. For more dishes from the same country, see our Japan page.
Ingredients: Serves 1
Equipment
- Kitchen scale
- Small saucepan
- Spatula
- Heatproof bowl
- Stable saucer
- Spoon
Choosing and Measuring
Kuzu powder: Look for food-grade powder labeled as hon-kuzu. Don't treat katakuriko, cornstarch or other starches as the same ingredient, because this recipe doesn't cover how they would behave. It also starts from purchased powder and does not involve refining kudzu root at home.
Sugar: White sugar is an editorial choice here. Brown sugar such as kokuto (黒糖) belongs to a different variation, not this basic cup.
Water: Use unheated drinking water, weighed in grams. Add it to the saucepan before any heat goes on.
Finished kuzuyu is hot and thick, so take care when pouring and before you drink it. This article gives no safe drinking temperature, and neither the look of the drink nor the doneness cues can tell you it has cooled enough.
Method: Mix First, Then Heat
Steps 1 to 4 all happen before the heat goes on. Steps 5 and 6 are the only cooking stage. Steps 7 to 9 are ordinary handling and add no further heating.
If It Doesn't Look Right
| What you see | When | What to do |
|---|---|---|
| Lumps in the liquid | Before heating | Keep mixing with the spatula until they are gone, and only then turn on the heat |
| Still cloudy | During heating | Keep stirring over the heat. Thickness alone does not mean it is done |
| Clear-looking but thin | During heating | Keep stirring until it thickens as well |
| A firm mass you could cut | At the end | This is past the intended texture. Check your weights next time. Adding more water is not part of this recipe, so we can't say how it would turn out |
Variations Beyond This Cup
Tengyokudo's page also suggests replacing the water with milk, coffee, black tea or soy milk, and it offers variations such as ginger or brown sugar. We have left all of these out, so the recipe above stays a plain cup of kuzu, sugar and water. If you want to try one, follow Tengyokudo's page rather than adapting the steps here.
Background: Kudzu and Yoshino Kuzu in Nara
A March 2025 report by Nara Prefecture, hosted on the website of Japan's Agency for Cultural Affairs, discusses the history of kudzu in Nara. It covers the use of kudzu root as both medicine and food, along with kudzu powder and Yoshino hon-kuzu. That medicinal history is a historical record only, and it tells us nothing about any health effect from drinking kuzuyu today.
The report connects the name "kuzu" with the place name Kuzu (国栖), but only as a theory, so we don't treat it as settled. It also describes the refining processes known as Yoshino-sarashi (吉野晒し) and kan-zarashi (寒晒し), the role of cold water and climate, and kudzu powder production in the prefecture.
The same report describes a regional definition of the Yoshino hon-kuzu trademark and kudzu-root starch as a raw material. We have not confirmed the current trademark or legal status, so use the report as history and rely on the package label when buying powder.
Frequently Asked Questions
How long does it take?
Tengyokudo gives no cooking time, and we have not timed it ourselves. Use the two visual cues in step 6 instead.
Can I make it in the microwave?
Other methods exist, but they are separate recipes. Maehara Seifun (the Gishi brand) describes dissolving the powder and sugar in a little water in a mug, adding more water or hot water, microwaving, and stirring until transparent. Its amounts and order differ from Tengyokudo's, so don't mix the two. If you want that method, follow its page from start to finish.
Can I pour hot water straight onto the powder?
Not in this recipe, where the unheated water goes in and is mixed before the heat goes on. Maehara Seifun also warns against adding hot water directly to lumps of kudzu powder.
Can I use katakuriko or cornstarch instead?
This recipe doesn't cover them, and we can't promise they will behave the same way or give the same drink.
Can I use a different kind of sugar?
Tengyokudo doesn't name a type of sugar, and white sugar is our editorial choice. Its brown sugar idea is presented as a variation, so it is not part of this basic cup.
Can I store or reheat it?
Neither recipe page we used gives storage or reheating guidance, so we don't offer any storage time or reheating method. The recipe makes one serving.
Is kuzuyu good for you?
This article makes no medical or nutritional claims. Kudzu's historical medicinal use in Nara does not show that drinking kuzuyu today has any particular effect.
Sources
- Inoue Tengyokudo Co., Ltd. (Yoshino Hon-kuzu Tengyokudo), "自分で葛粉から葛湯を作る方法" (How to make kuzuyu yourself from kudzu powder). Source of the single-serving amounts, the saucepan method and the optional variations, which were not adopted here. A specialist's published recipe, not an independent home test. https://www.kudzu.jp/hpgen/HPB/entries/204.html
- Maehara Seifun Co., Ltd. (Gishi), "葛湯の作り方を教えて下さい。" (Please tell me how to make kuzuyu). Used only for comparison: a separate mug and microwave method, its caution about hot water and lumps, and its burn warning. https://www.gishi.co.jp/home/faq_view.asp?id=96
- Nara Prefecture, "令和6年度「食文化ストーリー」創出・発信モデル事業 奈良の食文化（大和の保存食）情報調査・発信事業 調査報告書" (survey report on Nara's food culture and preserved foods), March 2025, hosted on the Agency for Cultural Affairs website. Used for the background on kudzu and Yoshino hon-kuzu. Our summary draws on an earlier reading of the Yoshino hon-kuzu chapter (printed pages 20–24), not the whole report, and is not a recipe source. https://www.bunka.go.jp/seisaku/bunkazai/joseishien/syokubunka_story/pdf/94217001_10.pdf
