Japan — Chinese-influenced technique fully integrated into Japanese home and restaurant cooking
Ankake (あんかけ) is the Japanese technique of thickening a sauce, broth, or dashi with katakuriko (potato starch) or cornstarch to create a glossy, coating, gently clinging sauce that keeps food warm longer than unthickened broth. The technique is used across categories: ankake tofu (silken tofu in thickened dashi-soy-ginger sauce); ankake udon (hot udon in thick, warming ankake broth — popular in Kyoto in winter); ankake chahan (fried rice covered in a silky thickened sauce); and in Chinese-influenced Japanese dishes like ankake yakisoba and sweet-sour pork. The starch gelatinises at approximately 65–70°C, creating a sauce that coats without pooling, retains heat exceptionally well, and has a characteristic 'glossy' visual appearance. The key failure mode is an uneven texture ('nameless' texture) from improper starch slurry addition.
The sauce itself has the seasoning profile of dashi-soy-ginger; the starch thickening adds no flavour but dramatically changes how the seasoning adheres to and enrobes the food
Starch slurry must be mixed just before use (potato starch settles rapidly); add to the simmering liquid gradually while stirring constantly; the sauce must return to a simmer after starch addition to fully gelatinise (under-heated ankake sauce breaks quickly); never add starch directly to hot liquid without mixing with cold water first (causes immediate clumping); allow to cool slightly before serving — peak viscosity occurs at 60–65°C.
Potato starch (katakuriko) creates a cleaner, more translucent gel than cornstarch — the Japanese preference; ankake proportion: approximately 1 tablespoon (10g) katakuriko per 200ml liquid; ginger is a non-negotiable flavour component in most ankake preparations (its warmth amplifies the sensation-keeping effect of the hot thickened sauce); the most elegant ankake is barely perceptible as thickened — it coats but doesn't pull as thick strings; the worst is lumpy and starchy.
Adding starch slurry to cold liquid (it won't gelatinise until heated — results in an unmixed, cloudy sauce); adding starch powder directly without making a slurry first (immediate clumping at hot surface contact); under-thickening and over-thickening (ankake should coat the back of a spoon, not be a gel; not be a thin broth — the consistency is between); making ankake sauce too early (it breaks and becomes stringy over time — make to order).
Japanese Cooking: A Simple Art — Shizuo Tsuji