KAWASAKI, Japan — For those who enjoy seafood, the rich marbling of tuna is what makes sashimi and sushi delicious, often determining its quality and price in the market. Traditionally, the level of fattiness in a tuna is assessed by a group of experts who cut into the fish using a large saw-like knife, a task that typically takes about a minute per fish.
However, modern technology is changing this practice. The introduction of a machine called Sonofai aims to streamline this process. Using ultrasound waves, this machine evaluates a tuna’s fattiness in a mere 12 seconds and can be operated by individuals without any prior experience in fish carving.
Developed by Fujitsu, a leading Japanese tech company, Sonofai’s name is derived from “sono,” indicating sound, combined with “f” for Fujitsu, and “ai” for artificial intelligence, altogether forming “son of AI.” This device impressively amalgamates its functional components as well.
The operation involves a conveyor belt directing a whole frozen tuna, roughly a meter (or 3 feet) long, into the machine. Sonofai then emits ultrasound waves, with sensors capturing these waves to generate a zigzag pattern on a screen that visually represents the fish’s fattiness levels.
In essence, fatty tissues absorb fewer sound waves than lean tissues, while the AI processes real data to filter out any misleading “noise.” According to Hisashi Ishida, president of Sonofai and head of Ishida Tec Co., which specializes in manufacturing food-processing equipment, using Sonofai enhances safety, hygiene, and efficiency in the industry.
“Fatty fish, known as ‘toro,’ offers a superior taste experience and is highly sought-after as sushi gains global popularity,” Ishida stated. Although there exists a grading system for beef based on its fat and expected flavor, the ability to measure tuna’s quality so accurately is a new advancement, said Hideto Okada, leading the AI sector at Fujitsu.
Sonofai employs a method similar to medical ultrasound scans. High-frequency sound waves, which remain inaudible to the human ear, are absorbed or reflected back, creating detailed images of hidden components, such as a fetus during pregnancy. Unlike other scanning methods like CT scans or X-rays, this technique does not use radiation, thereby safeguarding tissue.
Chris Edwards, a professor and medical doctor at Queensland University of Technology, specializes in training sonographers, experts in ultrasound technology. His studies focus on utilizing ultrasound to measure human liver fattiness, which can indicate diabetes and other health issues. “They can simply compare two fish and quickly identify which one has more fat,” Edwards remarked.
Yet, it may take some time before Sonofai becomes a tool for local sushi chefs. Initially, fish-processing companies and fishing organizations are the primary market for these devices. Launching officially in June, Sonofai is priced at approximately 30 million yen ($207,000) each and will first be available in Japan, with plans to extend into the U.S. and other regions globally. Future improvements aim to assess additional qualities, such as freshness and firmness, across various fish types.