When it comes to professionalism, only yellow mustard is mustard, and there is never such a thing as green mustard!
Yellow mustard is a real mustard and a treasure handed down by our ancestors. As early as the Zhou Dynasty, it has become a common seasoning for the general public. It is made by grinding the seeds of mustard, and is a member of a large family (Cruciferae) together with Chinese cabbage, potherb, cabbage and radish.
When mustard seeds are ground into powder, it becomes yellow mustard, and when it is made into sauce, it becomes mustard sauce. I must have eaten a hot dog handle for 2 yuan when I went to IKEA, so this sauce can be applied for free.
So what is green mustard? It says, it's the root of wasabi!
But you should also know that the price of wasabi from Japan is actually very high, so you often go to Japanese restaurants and cafeterias in five-star hotels to eat the kind of wasabi used for salmon ("wasabi sauce" similar to toothpaste), which is actually not real wasabi, but cheap wasabi.
Round and round, have a drink!
The first kind: mustard
Wasabi, which is often mentioned by the Japanese population, is only used by high-end Japanese restaurants in China's first tier cities. You usually get a small piece of fresh root and a small washboard, so do it yourself. In fact, the taste of wasabi is not too spicy, even with a little sweetness. However, because its spicy flavor volatilizes quickly and is not easy to preserve, it is expensive and it is unlikely to be used in domestic stores.
The second type: horseradish
This is the "green mustard" you can see in supermarkets, cafeterias and ordinary Japanese food stores, squeezed out of toothpaste restaurants. Its raw material is actually a rhizome called horseradish. Because horseradish itself is light yellow, merchants add food pigments and become "forgive green". Horseradish is widely used because of its low price and good taste!