Top-Quality Wild Tuna, Longline Catches the Winners at Toyosu Tuna Auctions

Checking a bluefin tuna for quality. A small cross-section cut from the tail is carefully examined using a flashlight to check the grain and condition of the meat. (© Kawamoto Daigo)

Wholesalers evaluate the quality of frozen tuna before the start of the auction. (© Kawamoto Daigo)

The tail cross-section is critical for evaluating tuna quality. Wholesalers and buyers look at the distribution of fatty tissue, the quality of the red meat—a measure of viscosity and umami—and overall color.

Blocks of tuna from the wholesale market on sale at a retailer catering to sushi shops and restaurants. Each block is marked with the name of its port of origin. (© Kawamoto Daigo)

A panel display at the Toyosu Fisheries Wholesale Market explains the hand gestures used in the tuna auctions. (© Kawamoto Daigo)

Kimura Kiyoshi, who heads the Sushi Zanmai chain of restaurants, uses a flashlight to check out a tuna at the Toyosu New Year’s auction. (© Toyosu Fish Market)