First of all, fish for sushi has a very special quality. You can not necessarily see that quality with your eyes. There are usually experts who have the knowledge and experience to be able to see that.
Also it is difficult to tell where the fish is coming from.
There are some fish that swim several kilometers a day. There are also fish that stay in the local area throughout their lives. There are areas in the world where fish are of better quality than elsewhere. Unfortunately, it also requires that you have an in-depth knowledge of it.
About Sushi course for beginners I talk more, how to make sure you get bought of a quality so that it is suitable to be used for sushi.
Zoë has lectured and held sushi courses for A. P. Moller – Maersk, Hugo Boss Nordic, Novo Nordisk, Novartis, Velux, Gorrissen Federspiel, Beierholm revision, Elbek & Vejrup and many more.