KAWASAKI, Japan — Seafood lovers know that the fatty marbling found in tuna is essential for creating delectable sashimi and sushi. Consequently, the industry often evaluates the fish’s fattiness to determine quality and pricing.
Traditionally, this assessment was done manually—cutting the fish’s tail with a large saw-like knife, a process that took about 60 seconds per fish. However, the introduction of the Sonofai machine streamlines this task drastically, accomplishing the evaluation in just 12 seconds. This revolutionary device can be operated by individuals without prior training in fish carving techniques.
Created by Fujitsu, the Sonofai machine combines ultrasound technology with artificial intelligence to gauge tuna fattiness. Its name derives from a blend of “sono,” meaning “sound,” “F” for Fujitsu, and “AI” for artificial intelligence, additionally hinting at its status as a ‘son of AI.’
A conveyor belt transports frozen tuna into the machine, which emits ultrasound waves that penetrate the fish. Sensors capture these waves and generate a zigzag diagram on a display indicating the fish’s level of fattiness. Remarkably, fatty tissues absorb fewer sound waves than lean ones, and the AI effectively filters genuine data from irrelevant noise.
Hisashi Ishida, president of Sonofai and head of Ishida Tec Co., which specializes in food manufacturing equipment, touted the machine’s efficiency, stating, “Fatty fish tastes good, feels better on your tongue, and is called ‘toro.’ Overseas needs are growing because sushi culture is now appreciated around the world.”
As noted by Fujitsu’s Hideto Okada, developments such as Sonofai mark a new frontier for the seafood industry. Unlike beef, which has a defined grading system for fat content and flavor, similar technology for grading tuna is relatively innovative.
Echoing principles seen in medical ultrasound scans, which utilize high-frequency sound waves to visualize hidden elements such as a fetus during pregnancy, Sonofai operates without the harmful radiation associated with CT scans or X-rays.
Chris Edwards, a medical doctor and ultrasound expert at Queensland University, discussed the technology’s precision in determining fish fattiness, explaining, “They can look at one fish and compare it to another and say, ‘Oh, that one’s definitely got more fat than that one.’”
Despite its advantages, Sonofai will not be available to individual sushi chefs initially. Its primary market includes fish-processing companies and commercial fishing organizations. Priced at approximately 30 million yen ($207,000), it is expected to launch in Japan in June, with plans for expansion to the U.S. and other regions. Future upgrades are also in the pipeline to evaluate the freshness, firmness, and additional qualities of various fish species.
