Kanten is made from tengusa seaweeds. Tengusa seaweeds are simmered at first, and jelly-like materials are firmed and freeze-dried. Kanten come in different forms, such as sticks and powder.
Kanten is a gelatinous substance that is essential in Japanese confectionery (wagashi). Unlike animal gelatin, kanten is a healthy, calorie-free food rich in dietary fiber, because being made from seaweeds. But the producers of natural kanten are now on the verge of disappearing.
The natural snow-dried method begins on Japan's coast, where tengusa seaweeds are harvested in the fall and sun-dried. The dried tengusa are bundled and taken up to the Nagano to be made into kanten during the cold winter months.
Beginning in December, the tengusa are placed in a large cauldron with water and allowed to cook down for several hours. The resulting gel is allowed to cool. It is then cut into blocks, arranged on bamboo trays, and set outside on snow-covered rice paddies. Moisture in the gelatin freezes each night then thaws during the day. In about ten days, all the moisture is gone and the light, flaky bars of pure kanten remain. The crisp, porous, feather-light bars are then shaved into fine flakes and packaged.
Kanten Diet regimen involves eating the red algae-derived product with meals or as a snack. Virtually calorie-free yet surprisingly filling, this high-fiber food works to make you feel fuller and thus eat less.
“It’s actually a traditional food,” says Tokyo-based cooking coach Horiike MIckey. “Japanese people have been eating it for ages.” The word kanten literally means “cold sky,” a reference to the centuries-old process of drying the trays of congealing agar in the sun on snow-covered rice fields. It can be eaten fresh (in a preparation known as tokoroten), though more often than not it’s freeze-dried and packaged.
The resulting powder or flakes can be reconstituted with water and flavored with just about anything to create a jelly. Horiike’s favorite is yuzu, which she makes by boiling 2g of kanten powder in 500cc of water and adding a few spoonfuls of yuzu citrus jam. When transferred to a shallow container, the mixture sets in about 30 minutes. “The beauty of it is, unlike gelatin, it sets at room temperature,” she says. “And of course, it’s totally healthy.”