Which kind of a raw tuna is suitable for sashimi and how can you recognize such in shop?

1. Color: The flesh should be a deep red color, not brown or grey.

2. Texture: The flesh should be firm and springy, not mushy or watery.

3. Smell: The tuna should have a fresh, briny smell, not a fishy or ammonia-like odor.

4. Eyes: The eyes should be clear and bright, not cloudy or sunken in.

5. Gills: The gills should be pink or red, not pale or brown.

6. Skin: The skin should be smooth and shiny, not dull or wrinkled.

In addition to these visual cues, you can also ask the fishmonger about the freshness of the tuna and where it was caught. If possible, try to buy tuna that was caught in the same region as where you live, as this will ensure that it is as fresh as possible.

Some specific types of tuna that are commonly used for sashimi include:

* Bluefin tuna: This is the most prized type of tuna for sashimi, and it is known for its rich flavor and melt-in-your-mouth texture.

* Yellowfin tuna: This type of tuna is also very popular for sashimi, and it has a slightly milder flavor than bluefin tuna.

* Bigeye tuna: This type of tuna is less common than bluefin and yellowfin tuna, but it is also very good for sashimi. It has a slightly firmer texture than the other two types of tuna.

When in doubt, it's always best to ask a professional fishmonger for help choosing the best raw tuna for sashimi.