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Dashi and the gusto and unbearable lightness of umami,

To most people who will read this you will have heard of Dashi and associate it with instant Japanese cuppa soup. You are not wrong, but it has a deeper story.

At its most basic point it is a stock made with water and a type of kelp seaweed called Kombu Kombu is where umami was discovered and is the reason I am writing a page about Japanese stock. You can read a basic background about Kikunae Ikeda, the professor at Tokyo university who discovered it by googling him. It is good to know about him. But this page will have lost you all after the third paragraph, all but the most devoted readers before getting to the cooking part if everything is included about that history.

Kikunae Ikeda isolated and discovered Kombu seaweed contains glutamate, an amino acid and salt which on its own doesn’t have an obvious amount of flavour. However when mixed with other amino acids it enhances the power of their flavour multiple times.

This is a terrible way to explain it, but how I try and inform people is using an equation 1 + 1 = 3.

We all know 1 + 1 = 2, but in the case of your taste buds it registers a 3.

Ingredient which are technically greater than the sum of their parts.

The additional extras to glutamate (Kombu) come from different parts of the pantry.

Dried meat, Katsuobushi or dried anchovy gives Inosinate. Mushrooms and plants give Guanylate,

Soy beans, grains and dairy provide Arginine.

These three additional extras are the basic materials which make up DNA and RNA. They are simple molecules which to bond with glutamate in different forms of traditional Dashi.

The instant soup you will all know will a combination of kombu and katsuobushi (glutamate and inosinate) or shiitake Dashi (glutamate and Guanylate) or miso soup (glutamate and Arginate).

These ingredients can all be combined in different ways to enhance each other. This give dashi its depth. A really good Dashi stock is an odd and incredible thing, it is a powerful flavour but sometimes so unbearably light it is hard to register its flavour, but you can’t stop enjoying it.

There are a number of other molecules which bond with glutamate to enhance their flavours, these are part of typical ingredients, potassium, iron, glycine, sodium and calcium.

This is where the flavour layering gets interesting in commercial kitchens. Its why the outcry of what’s wrong with just making a lemon tart falls on deaf ears in the kitchen. Why everything is miso flavoured these days, from mayonnaise to custard. Why chefs make seaweed and mushroom desserts.

Everything is dry aged, from fish and meats. Vegetables and dairy are fermented.

The reason is the processes creates free glutamate which enhances the flavour.

Chefs poach or blanch vegetables in Kombu dashi instead of water, they marinade cooked vegetables in the stocks.  The iron, sodium and potassium in greens taste brighter and more vivid.

Meat and fish are marinaded in small amounts of shio koji (fermented rice) which adds umami and also contains an enzyme which breaks down and tenderises the protein in the meat. Its a fairly tasteless ingredient, but makes roast meat taste much better, .

Sauces like XO or variations have become typical on menus because of their high quantities of dried seafood and aged cured meat. I love the stuff even though it smells like wet feet. It should be off putting. The sauce tastes good because of the umami, Spinach tastes good because of the potassium and iron, together they taste incredible, 1 + 1 = 3.

Its another feather in the hat of the simple aint simple brigade. But for umami it is especially true.

Back to Kombu, and how to make dashi, there are a number of ways to make it.

Kombu Dashi

From my experience there is one best way. The right ratio of water to seaweed, at the right temperature.

15g of dried Kombu to 1 Litre of water.

Heat it gently to 65 degrees and hold it between 65 and 70 degrees for 1 hour. I give it a little stir every now and again. But for the most part treat it like a tea. If the temperature drops below 60 heat a little longer. Make sure not to boil or keep it too hot or it can thicken and get a little bitter.

You can use the Kombu twice, it is superior for the first extraction. But still gives a good amount of glutamate for the second. Dry and keep your left over kombu, there are plenty of great recipes which will be added to this blog on how to reuse them.

Bonito Dashi

To make katsuobushi dashi you simply need to bring your strained kombu dashi to the simmer and drop in shaved bonito flakes, I use the ratio of 20g of bonito flakes per Litre of Kombu Dashi.

Immediately turn the stock off the heat and let the flakes settle to the bottom of the pot. Allow to steep for 3 minutes or so and strain out the flakes. (You can make a second batch from the flakes as well by repeating the process, I tend to use the first for soup and the second for cooking.

This is a great liquid for cooking, to simmer or braise vegetables. For broths with noodles. Or to poach or serve with seafood or tofu.

It is also an incredible savoury drink with the addition of salt or white soy sauce if you have it available.

Mushroom Dashi

Mushroom dashi can be made with most varieties of mushrooms, dried is far superior to fresh as the drying process changes the guanylate molecule and makes its flavour more powerful with the glutamate from kombu.  Shiitake are the most used variety for this as they have the highest available quantity of guanylate of the commercial mushrooms.

The extraction for this broth is less instant than bonito flakes. A number of recipes for mushroom dashi will as you to simmer the mushrooms from dried, it makes a nice broth, but for maximum umami extraction the mushrooms need to be soaked cold then cooked.

30g of dried shiitake mushrooms per litre of kombu dashi.

1. Soak the dried mushrooms in the kombu dashi at 5 degrees C for 10 hours (best to do this in the fridge)

2. Heat the broth and mushrooms quickly to 70 degrees and hold for 15 minutes.

3. Strain and reserve to use.

As a basic stock this is wonderful to use cooking rice, and is my general go to for making miso soup as apposed to bonito stock. As a simple broth or tea I like to simmer a little ginger, soy and mirin when I heat the stock.

The reason to heat the broth quickly to 70 degrees is between 40 and 60 degrees there is an enzyme in the mushrooms with breaks down the guanylate lowering its umami.

Above 90 degrees the mushrooms RNA is denatured and less available.

A tricky tight rope. But don’t worry its not ruined if it does boil, this is the technical advice.

Save your mushrooms for another use. They will be delicious added to a stir fry or salad dishes.

Combining these techniques makes broths even more layered, using dried scallops, abalone or anchovies instead of/or in addition to bonito flakes makes a very special soup. Adding chicken or ham stock adds glycine and calcium, onions, leeks and ginger add layers.

Different miso pastes, soy sauces, mirin or sake all give additions to broths.

All the examples given are very Japanese as this is where the methods came from, having said that its not unheard of for chefs to add tomato or parmesan rinds to their broths to extract available umami for their dishes.

Most umami applications you hear about are very explosive, they taste great, miso and soy sauce are great, fermented chilli hot sauce and kimchi are incredible. Umami bombs.

There its an understanding about lighter touch with umami which makes the best the best.

Knowing how to make things taste more intense, without intense ingredients or invasive cooking methods. Dashi is were it was discovered, when you understand why dashi works, you can understand how umami works. How 1 + 1 = 3

You will probably reach for less salt and sugar and reach for different ingredients to make your chicken, spinach, tomatoes and potatoes better.

or just enjoy a different approach to your cuppa soup

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