The Significance of "KOKU" in Japanese Cooking

By Umami Recipe
The Significance of "KOKU" in Japanese Cooking

You may have come accross the word "koku" in Japanese cooking; an expression used to signify the depth and richness of foods. The phrase "koku ga aru", which means "it is full of rich flavor", is often used to describe a delicious dish, but there is more to koku than just this. In this article we look at the ideas behind koku and how to make your dishes rich in a way that may elicit "koku ga aru!" from your Japanese guests.

Japanese and Non-Japanese Cuisines

Japanese cuisine is often characterized by its seasonal and natural flavors of ingredients with delicate seasoning. Commonly served are dishes that do not require the use of heat--baking, frying, steaming, etc-- such as sashimi and raw vegetables. In addition, there are many dishes that use kombu (kelp) and iriko (dried sardines) to make "dashi", or broth for nuanced tastes with depth and character. Simple seasonings and natural tastes and textures form an important part of Japanese food culture. 

If we were to draw out some differences between Japanese and non-Japanese cuisines, we could start with the use of wheat based foods, like pasta and breads, which are a prominent part of many non-Japanese food cultures. The counterpart to wheat would be rice in Japan, which traditionally is the staple food product that the other dishes compliment. Another feature of non-Japanese cuisine is the use of wines and an abundance of spices. Heat, in the form of frying, baking, steaming and the like, are used to cook the foods, along with many other innovations in food preparation.

Of course, characterizations like this will always be problematic, with both Japanese and non-Japanese cuisine sharing more with each other than not. For example, Japan and many other food cultures have developed methods to create nuanced and deep tastes, or what the Japanese would call "koku". Dashi, soy sauce, mirin and Japanese cooking wine are a few koku enhancing ingredients commonly used in Japanese kitchens. If we look abroad, there are koku enhancers like Dasida in Korean cuisine, which is a delicious way to draw out flavors of beef, and Tenjang, a Korean-style miso. In Chinese cuisine, beet and bean sauce are another seasoning that not only flavors the dish but also gives it a deep richness.

How to Identify the Koku of a Dish

To be precise, koku is not so much a taste, but rather an expression that includes multiple sensory inputs, like aroma, texture and even the aftertaste of foods. Simply put, it is a catch-all phrase when complimenting foods with complexity and richness. 

The word "koku" derives from the word meaning "harsh" or "dense," and also comes from the Chinese character for "ripe grain". In more scientific terms, it is said that a compound called glutamyl-valyl-glycine is what gives koku its full flavor. "Umami" is another Japanese expression used in a similar way to koku, but is different in that umami does describe taste. Umami is just one of the many types of flavors, in the same category as sweetness, saltiness and bitterness. If you eat something that only tastes good, but has no texture, aroma, or flavor, you cannot say that it has koku. Full-flavored foods can be complex experiences that are nuanced and persist on the tongue and after swallowing. Though, not all dishes are meant to have an abundance of koku. If you take a dish that is meant to be fresh and citrusy, and add ingredients that douse it down with koku, it will ruin the intended taste.

The Impact of Koku on Foods

The dishes that tend to be rich in koku are those that melt together several ingredients or those that have been cooked over a long period of time. These are mainly curries, stews, ramen soups, and other rich dishes. In addition, fermented foods such as cheese are also rich in koku. 

On the other hand, vegetables, fruits and other unprocessed foods are less likely to be rich. Dishes and foods that are not cooked with heat usually have less koku because the focus becomes the natural taste of the ingredients. But because the richness of a dish is not the same as the satisfaction derived from the meal, less rich dishes can be just as enjoyable. Prime examples are salads and fruits, which have little koku, but are delicious. If we were to use curry to explain koku and deliciousness, we can take two types of curry; one that is thick and stewy, another that is light and watery. The thick curry is regarded as richer than the light curry, but whether it is more delicious is another matter. Oftentimes, it comes down to preference or the occasion as to which is more satisfying. 

If you pinch your nose so you can't smell, and eat curry that is considered to be rich, the tasting experience will be reduced by half. This is because by cutting off your sense of smell, the aroma, richness, persistence, and spread of flavors unique to curry become weaker. 

For koku, it is important to have a balance of the following five tastes: sweetness, umami, bitterness, sourness, and saltiness. For example, a dominantly sweet curry or a very spicy curry will not have a rich taste. People with a sweet tooth or those who like spicy food may find it enjoyable, but they are unlikely to feel the full richness of a curry that is balanced. A dish with a strong sense of koku is one that is both complex and well-balanced.

Koku Enhancers

The key to bringing out the koku of a dish is being mindful of the complexity and balance of the eating experience. Raw ingredients, or those that are prepared in a simple way are unlikely to have much koku. Drawing out koku usually requires adding heat, fermenting and the addition of seasonings. This will not only accentuate the flavor of the ingredients, but also broaden and sustain the flavor, adding the sought after koku.

The two most important ingredients for koku are umami and fats. Umami ingredients are the base of koku, and when they mix with raw ingredients, they draw out flavor and persistence. For example, if you don't add umami seasoning to miso soup, the taste will be weak. However, when umami ingredients are added, the flavor becomes stronger at once. An example of an umami ingredient is coffee powder. If you add coffee powder as a secret ingredient to a curry roux, the flavor will become more complex and the richness will be pronounced.

If you feel that your dish lacks koku, one reason may be that it is not cooked for a long enough period of time. If the food is not cooked well, the flavors will not be fully infused. It is important to heat the food thoroughly to bring out the flavors of the ingredients in combination with any seasonings and spices.

Another reason for a lack of koku often comes from substituting key ingredients for others. For example, if you are making tomato cream pasta, you would normally use fresh cream, but if you substitute it with milk, as it has a lower fat content and is lighter than cream, the outcome will be less koku. 

Finally, a lack of salt can greatly reduce koku. If it is not salty enough, the taste will feel thin and insufficient. Make sure to season well.

Being Aware of Koku in Everyday Meals

This article was about the koku of a dish, described by the fullness and complexity of the eating experience. Koku is a positive factor that invites several of our senses to appreciate and enjoy the dish. 

But koku is not everything. Dishes such as fruits and salads that are not rich in koku can still be nourishing and delicious. However, dishes such as curry and stew are more likely to be considered delicious when they are rich in koku. If koku is your goal, then this can be achieved by adding a little extra effort to your everyday cooking.

Umami Recipe Team

Bringing what's new on Japanese food and culture, from traditional to current trends to your home.

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