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Tuesday, 26 April 2016

The science of making dashi

Over his loaded schedule as chef-owner of Kyoto’s three Michelin-starred Kikunoi restaurant, Yoshihiro Murata travels the world to spread the word about washoku. The traditional Japanese cuisine was listed by Unesco as an intangible cultural heritage of humanity in 2013 and Murata played no small role in campaigning for its listing.


The science of making dashi
Guests were served a bento box lunch of yakimono (grilled fish), glossy tiger prawn, roast duck, seafood paste stuffed shitake, sesame seed tofu, dashi and wasabi jelly with dried scallop rice. Photos: The Star/Faihan Ghani
The venerable chef and goodwill ambassador for Japanese cuisine was in Kuala Lumpur earlier this year to give a demo on making dashi, a stock con-sidered to be at the centre of Japanese cuisine. It has been said that in Japanese cuisine, all roads lead to dashi, the base of all that is umami and yummy.
While making dashi by boiling together kombu seaweed and dried bonito fish flakes makes a reasonable dashi, there is a better way to do it, said Murata who is a Great Master of Traditional Japanese Cuisine and chairman of the influential non-profit Japanese Culinary Academy.
Brewing New Style Dashi with morel mushrooms, dried tomato and minced chicken breast meat.
Brewing New Style Dashi with morel mushrooms, dried tomato and minced chicken breast meat.
Together with Kyoto university researchers, Murata has found the optimum method for making dashi – or how to extract the maximum umami flavour by controlling heat and timing.
Murata’s recipe calls for soaking 50g of kombu (kelp) in water for an hour at 60°C as it is the optimum temperature for extracting umami, widely known as the fifth flavour element.
The seaweed is then removed and the water temperature raised to 80°C before papery shavings of dried bonito (katsuobushi) are added.
The tuna flakes are allowed to steep in the stock for just 10 seconds before being strained to avoid over extraction and gaining of unwanted taste elements.
The water for dashi is not allowed to come to a boil but if it happens, the umami is still there but the taste of the dashi will be different – clarity and a clean, delicate and nuanced savoury and sweet taste are what define excellent dashi from the merely good.
Dried morel – ot shiitake – mushrooms can be used instead of dried bonito flakes to make a vegetarian dashi.
Dried morel – ot shiitake – mushrooms can be used instead of dried bonito flakes to make a vegetarian dashi.
“For hundreds of years, we have been making dashi the wrong way,” said Murata through an interpreter, referring to the common practice of boiling kombu and katsuobushi to make dashi.
While his cooking is rooted in tradition, the chef – who always carries a thermometer in his sleeve pocket – takes a progressive approach to cooking which does not preclude the use of science to allow him to accurately communicate Japanese cuisine to the world.
The world’s most unconventional chefs, Ferran Adria, Hes-ton Blumenthal, Rene Redzepi and Pascal Barbot have all spent time in Murata’s kitchen.
His legendary restaurant Kikunoi has stood at the foothills of Kyoto for more than a century (established 1912 during his grandfather’s time), serving an elaborate parade of washoku dishes in a multi-course kaiseki ryori, the equivalent of the western degustation menu.
“There are 65 different items in a typical kaiseki ryori course and only 1000 calories,” said Murata. In comparison, a hamburger has about 1800 calories and a French meal of 25 items has about 2500 calories.
“So many chefs are curious about how we achieve this.”
Japanese cuisine is one based on seafood, grains and vegetables. For nearly 300 years (from 1635) Japan practised a closed door policy limiting trade and travel to curb the spread of Christianity by missionaries.
“For almost 300 years we had no meat and developed a taste for using only umami to enhance flavour,” Murata said, adding that there is zero calories in umami whereas 1g of tasty fat has 9 calories – so one can lose weight by replacing a meal with three bowls of miso soup made with dashi!
Dashi, a deceptively simple, clear broth at the heart of one of the world’s greatest cuisines, uses just three ingredients – seaweed, dried tuna and water – to produce a liquid with a maximum of umami, that savoury, meaty taste that coats the mouth and feeds the soul.
What gives kombu its high umami are two amino acids, glutamic and aspartic. When bonito flakes are added, the glutamate of kombu and the inosinate of bonito flakes produce a synergistic effect.
“The two together gives you eight times the umami effect,” said Murata impactfully to a roomful of chefs, restaurateurs, corporate personalities, ambassadors and media at the residence of Japanese ambassador Dr Makio Miyagawa.
“And to make it taste sweeter, add a little salt to the dashi,” he said.
Dried tomato has as much glutamic acid as kombu and can be used as a substitute in dashi making.
Dried tomato has as much glutamic acid as kombu and can be used as a substitute in dashi making.
Murata said vegetarians can make a dashi using dried mushrooms like shiitake and morel to replace the bonito flakes. Dried shiitake and morels also have high content of another umami substance, guanylate. Guanylate in a raw mushroom is rather low but is very high in dried mushroom.
Murata then demonstrated how to make a new style of dashi without kombu or bonito flakes!
In this new recipe, kombu is replaced by dried tomato – which has about the same amount of glutamic acid as kombu – and bonito flake is replaced by dried shiitake or morel mushrooms.
The dried ingredients are soaked overnight and then boiled in water together with some chicken breast to make a light and clear umami-packed stock in about an hour of simmering.
Dashi has a different taste profile from that of western-style stock but in both techniques, chefs are aiming to extract the umami taste of the ingredients. Free glutamate is one of the major amino acids found in various types of stocks, and it is rapidly extracted from food ingredients in the early stages of cooking, reports Kumiko Ninomiya in her article “Science of Umami” published online at BioMed Central.
“The use of ingredients high in umami such as dried kombu and bonito allow for a tasty stock to be made quickly. Kombu is dried slowly over a long period of time to remove moisture and odour, and boiled fillet of bonito is smoked and sprayed with a mold culture (Aspergillus glaucus) to make the hardest food in the world.
“Umami is concentrated in advance in these ingredients and can be rapidly extracted during cooking. Thus, cooking time for dashi is considerably shorter than in making a western stock” – which may require hours and days of simmering.
Goodwill ambassador of Japanese cuisine Chef Yoshihiro Murata of the three Michelin-starred Kikunoi restaurant in Kyoto was in KL to demonstrate the perfect way to make dashi with dried kombu seaweed and bonito flakes.
Goodwill ambassador of Japanese cuisine Chef Yoshihiro Murata of the three Michelin-starred Kikunoi restaurant in Kyoto was in KL to demonstrate the perfect way to make dashi with dried kombu seaweed and bonito flakes.
However, dashi has only a few amino acids while western soup stocks have more, including glutamate, alanine, and arginine.
Although the free amino acid profile of dashi is simpler, miso, a fermented soybean paste, can be added to dashi to add a variety of free amino acids to make miso soup. As a result, the total free amino acid content in miso soup and consommé is quite similar, according to the report.
Together with soy sauce and other seasonings, dashi helps reduce caloric intake and the danger of obesity compared with dishes that use oil or animal fat.
According to Nutritional Neuroscience, an international journal on nutrition, diet and nervous system, daily ingestion of dashi, even at low concentrations, reduces anxiety and alters amino acid levels in the brain. “Daily intake of dashi has also been shown to improve mood status such as tension-anxiety in humans,” the journal says.

ICHIBAN DASHI

30g kombu dried seaweed
50g dried bonito flakes (katsuobushi)
1.8 litre water
Wipe the surface of the kombu with a moist towel. Place the kombu in a saucepan with the water and heat it up to 60°C on very low heat. Let the kombu steep for 1 hour at 60°C.
Remove the kombu and bring the broth slowly up to 80°C. Remove the pan from heat and add the dried bonito flakes to the broth.
Leave bonito flakes to soak for 10 seconds – just about the time it takes the flakes to sink to the bottom of the pan – then remove the flakes by straining through a fine sieve or muslin bag without pressing – pressing may extract bitterness.
Murata always carries a thermometer around to measure the temperature of his dashi stock, crucial to getting it perfect.
Murata always carries a thermometer around to measure the temperature of his dashi stock, crucial to getting it perfect.

NEW STYLE DASHI

10g dried tomatoes
10g dried morrel mushrooms
200g chicken breast meat
4g salt (or 2% of meat weight)
2 litre water
Soak the dried tomatoes and dried mushrooms in the water overnight. Remove any visible fat from the chicken breast and grind the meat with a food processor. Add salt to the meat, mix well and set aside for 1 hour.
Tip the tomato, mushroom and water into a saucepan. Add chicken and bring to a gentle boil over medium heat.
When chicken is cooked, remove from heat and strain the dashi through a fine sieve or muslin filter bag.