TOKYO: The nation's favourite snack comes in a bewildering array of varieties — from soy sauce to garlic, eel and shark fin — but the creation of ice cream that does not melt is a work of Japanese genius.
Across Japan, temperatures are beginning to rise as the "tsuyu" rainy season runs its course and the public braces for the all-pervasive humidity that is a feature of the summer in these islands.
Until the heat breaks in the latter part of September, there will be little relief from the sticky heat — and perhaps even more so this year as the long-range forecast is of a particularly hot summer.
As the temperatures soar, so do sales of a snack for which the Japanese notoriously have a sweet spot — ice cream.
The Japanese have enthusiastically embraced ice cream since it was introduced by some of the first foreign traders via the port city of Yokohama in 1878.
Domestic brands do a roaring trade alongside multinationals such as Haagen-Dazs, but some of the most innovative flavors have been devised by artisan manufacturers. And while it is not clear why, a good number of those companies are concentrated in the historic town of Kanazawa, in Ishikawa prefecture, which has earned it the title of Japan's ice cream capital.
Soy sauce flavour ice cream
"We are a specialty condiments manufacturer, but about 15 years ago we decided to try something a little different," said Eiji Tashiro, a spokesman for Yamato Soy Sauce and Miso Co, which is based in the city.
"We thought that as the Japanese people really like fermented foods and traditional ingredients, such as soy sauce and miso, we might be able to put those tastes into ice cream," he told DW.
The result is a combination of soy sauce in a vanilla ice cream that has proved remarkably popular, Tashiro said.
"I think most people are surprised when they try it for the first time because it does not really taste like soy sauce," he said. "When it is worked into the ice cream, it tastes more like caramel."
A stroll through the city, which is famous for its castle, impressive traditional gardens and no fewer than three geisha districts, will reveal just why Kanazawa is so associated with ice cream.
Artisan makers sell ice cream speckled with gold leaf, "hojicha" roasted green tea or varieties made with sake rice wine. The Nakatani Tofu company makes, inevitably, tofu ice cream, while cones elsewhere are topped with swirls of black sesame ice cream, chestnut, "adzuki" sweet beans or black vanilla.
Another favourite, particularly in the spring, is the cherry blossom-flavored ice cream, as well as roasted sweet potato.
An ice cream that won't melt
It is also appropriate that ice cream that does not melt was concocted in Kanazawa — albeit by accident.
Scientists at Biotherapy Development Research Centre Co were collaborating with scientists at Kanazawa University on a strawberry polyphenol powder for use as a healthy, natural flavouring. But then they discovered that when combined with water and frozen, it is virtually indistinguishable from ice cream — but it does not melt, even when it is exposed to direct heat for an extended period.
First released by Kanazawa Ice Co in April 2017, the ice creams come in a variety of flavours and shapes on a stick, selling for around 500 yen (140 baht) each.
With the arrival of summer, an ice cream theme park opens in Sunshine City, a vast shopping complex in the Ikebukuro district of Tokyo, where makers from all across Japan congregate to show off their wares — many of which incorporate ingredients unique to their parts of the country.
Ice cream with slivers of raw horse meat — a delicacy in southern Japan — vies for the attention of consumers alongside tubs of rice-flavored ice cream from the paddy fields of central Japan, and a "chicken wing" variety from Nagoya, which is famous for the dish.
Elsewhere, ice creams are the flavor of potato or carrots, the squid ink variety is black, naturally, while the chili pepper version has a kick to it. Other varieties taste of crab, sunflowers, shrimp, eel, baked eggplant, black sugar or garlic.
While some are labeled as ox tongue, noodles, shark fin, viper, silk or curry, others are made with octopus, cucumber, beer, brandy or pear wine. The caviar version is predictably pricey, at 1,500 yen for a small tub.
"I am not a fan of all these exotic or strange flavors in ice cream, I much prefer something simple, like vanilla or green tea, but there is certainly something special about ice cream in the summer," said Kanako Hosomura, a 38-year-old mother of two from Yokohama, south of Tokyo.
"Ice cream was a real luxury when I was a child, so in my mind I still think of it as something we could only enjoy on special occasions," she said. "The highlight of our summer was always the holiday at the beach with my family and my father would always treat us to ice cream.
"Even now, eating an ice cream on a beach with my children will remind me of those days," she said.
Does ice cream deliver a mental boost?
There is even research to suggest that eating ice cream can make a person more active and reduce mental irritation.
Yoshihiko Koga, a professor at Tokyo's Kyorin University, carried out a series of clinical trials in 2016 in which test subjects ate ice cream immediately after waking up. They were then put through a series of mental exercises on a computer.
Compared to a group that had not eaten ice cream, Koga's subjects exhibited faster reaction times and better information processing capabilities, the Excite News website reported.
Monitoring of the subjects' brain activity revealed an increase in high-frequency alpha waves, which are linked to elevated levels of alertness and reduced mental irritation.
The professor has not reached any firm conclusions on precisely why ice cream delivers a mental boost, although one possible explanation is that it triggers positive emotions and added energy.
