In Japanese cuisine, it is common for the same cooking method to have different names depending on the season or context, which often leads to confusion. A good example of this is the distinction between yushimo and yakishimo. While they are similar, they are not identical, and understanding the difference is important.
The word shimo (霜) literally means “frost.” In cooking, shimofuri refers to a preliminary treatment in which food is briefly exposed to heat—by pouring boiling water over it, dipping it in hot water, or lightly searing it—so that the surface turns white, resembling frost. It is suitable for fish with beautiful skin or fish that are delicious when eaten with the skin on.
It also refers to the preparation step, similar to kawasimo or yushimo, where the fish is briefly dipped in hot water to remove scales and bloodline before preparing Arani (粗煮) or kabutoyaki (兜煮).
Shimofuri technique removes odors, sliminess, and excess fat while sealing the ingredient’s umami. It also firms the flesh and adds elasticity.
Yushimo (湯霜) comes from yu (hot water) and shimo (frost). It is a type of shimofuri in which the surface of fish or meat is treated with boiling water, either by dipping it quickly into hot water or by pouring hot water over it. The food is then immediately cooled in ice water and the moisture is removed before further preparation. This method is also known as yubiki (湯引き).
When used for sashimi, it is called yushimozukuri (湯霜造り). In this preparation, hot water is poured over the skin side of a fish fillet to soften the skin, after which the fish is chilled, the moisture is removed, and it is sliced. The result is an elegant appearance, with curled skin that enhances both flavor and presentation.
The term yushimozukuri refers not only to the cooking technique itself but also to the sashimi dish prepared using that method.
Yakishimo (焼霜), on the other hand, comes from yaki (to grill) and shimo (frost). This method involves lightly searing the surface of fish or meat until it develops a touch of browning, then cooled in cold water. Like yushimo, it removes excess fat and odor, but it also imparts a subtle roasted aroma. When used for sashimi, it is called yakishimozukuri (焼霜造り). This preparation is widely applied to fish such as red seabream, chicken grunt, barracuda, largehead hairtail, blackthroat seaperch, daggertooth pike conger, yellowtail, Spanish mackerel, bonito, and mackerel.
Depending on the style, the fish may be seared while still in fillet form (saku), or after being cut into sashimi slices. Just like yushimozukuri, the term yakishimozukuri refers both to the cooking method itself and to the sashimi dish created through that method.
Additionally, kawashimozukuri (皮霜造り) refers to sashimi in which the skin has been blanched in boiling water or over an open flame. This technique is also called matsukawazukuri (松皮造り) because, when applied to fish such as sea bream, it creates a pattern that resembles pine bark (matsukawa means pine bark). It enhances the umami of the skin while eliminating any fishy odor. It has the same meaning as Shimofuri and Yushimo.
In short, both yushimo and yakishimo are forms of shimofuri. Yushimo uses boiling water, while yakishimo uses direct heat from searing. Though their purpose is similar, each creates a distinct flavor, texture, and visual appeal, showcasing the ingredient in a uniquely Japanese way.
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