“Sashimi” implies more than just “raw fish.” The term refers to specific requirements regarding fish freshness, appearance, presentation, texture and taste.
Sashimi is a traditional Japanese dish made from thin slices of premium quality raw fish. Only genuine premium quality fish will garner a good price on the sashimi market.
Fish quality is determined by several factors, both biological and non-biological:
• Biological factors such as species, age, size, degree of sexual maturity, and the presence of parasites or diseases, are important. The size, species and stage of sexual maturity are very important because they influence the fat content of the fish. The tuna with the highest fat content attract the best prices in the sashimi market.
• Non-biological factors are often important and under the harvester’s control. They include fishing method and handling and chilling techniques used after capture.
There are many ways of handling and packing fresh tuna, but only a few are suitable for high-grade sashimi. In order to keep the fish in prime condition, the internal temperature must be lowered as quickly as possible to 32°F (0°C) and then maintained at this temperature during onboard storage, unloading, packing and transport.
To obtain a top-quality product, use the following two-stage chilling procedure:
• Lower the internal temperature of the tuna by placing it in slurry of flaked ice and seawater (2 parts ice to 1 part seawater).
• After 24 hours, transfer the tuna to a holding cooler and pack it well under ice. No further handling is required until you arrive at the dock.
Contributed by David Green