Real wasabi loses its flavor and pungency very quickly – 15 to 20 minutes can make or break the flavor experience. Because the wasabi plant is so hard to grow, real wasabi is very rare and expensive, most wasabi is a green paste that is really made from horseradish, mustard and food coloring. Other source of wasabi include China, New Zealand, Taiwan. Wasabi is also known for how spicy, or hot it is. If you're anything like us—true wasabi and ginger fans—you likely fall into two pools. Either you portion out a small bead of the green paste and slather it onto spicy tuna, or you stir the chunk of wasabi into the soy sauce dish to upgrade your dip. 01, 2019 Here's what that green paste that comes with your sushi is really made of. They have a mildly spicy flavor that makes for a unique salad option. Wasabi is ground from the root of the Wasabia Japonica, so after the 15-minute mark, wasabi starts to lose its freshness. So prepare accordingly. When cooking with wasabi, you want to use it fresh. The “Wasabi” You Get in Asian Restaurants Isn’t Really Wasabi Meghan Jones Updated: Apr. Wasabi leaves are tasty too. Sushi joint frequenters either love or hate the spicy accouterments their rolls are served with. Wasabi packs a powerful punch when eaten immediately after preparation. Wasabi is generally used in moderation in Japanese cuisine, and when real, fresh wasabi is used, instead of the mustard/western horseradish mix that's more common, it's more pungent than spicy. The less fresh wasabi is, the less intense the spicy ingredient will be.