How We Grade Tuna:
A Chubby Fish grading system primer.
Grading tuna is an art. Our team has inspected tens of thousands of tuna worldwide and we are confident we can accurately determine what a fish is worth. We are skilled at matching the right fish to the right customer, whether it is headed to Japan to be sold at auction or perfect for a local customer.
We take note of its shape from the minute the fish hits the dock, checking for any gashes on the skin, examining it again after the fish is iced, inspecting the body inside and out. We consider how it was caught: by rod and reel, harpoon, longline or trap. Our methodology is focused and precise; each step of the process helps in determining the value of a specific fish.
To evaluate our tuna, we first cut a sample from the tail of each fish and grade it in the following categories.
Is the meat dark or light? Is it clear or opaque? Where within the range of reds does it fall? Is it a darker red, closer to raspberry, or bright, like a cherry life-saver?
Fat content. Can you see creamy, marbled, "mature" fat, or is the fat loosely connected, wispy or "young"? Is the meat oily to the touch or does it feel watery? Does the meat seem dry or hard when you press on it with your fingers?
Shape. Is the fish long and lean or is it shaped like a football? Does it appear to have a belly? Is there a large cavity between the skeletal structure and the skin of the fish, or do they appear to be connected?
Core. We also take a sample from the core of the tuna, using a long, thin metal instrument called a sashibo. This probe is plunged into the fish above the pectoral fin, along the lateral line, whereby a tube-like piece of meat is extracted, about seven inches long. We then compare it to the tail sample, considering its overall texture, including color and visible fat.
We evaluate the core sample separately for both color and fat, each gets an individual grade and then the core gets an overall grade. This information is used together with what we have learned from the tail sample to determine the final value of the fish.