There are some common ways to qualify matcha:

1. Grade: Matcha can be qualified by its grade, with higher grades typically being more expensive and higher quality. The highest grade is ceremonial grade matcha, followed by premium grade, culinary grade, and ingredient grade.

2. Flavor: Matcha can be qualified by its flavor, which can vary depending on where it was grown and how it was processed. Some common flavors include vegetal, grassy, and slightly bitter.

3. Color: Matcha can also be qualified by its color, which should be a vibrant green color with no hints of brown or yellow.

4. Texture: Matcha can be qualified by its texture, which should be smooth and silky without any graininess or clumps.

5. Scent: Matcha can also be qualified by its aroma, which should be fresh and grassy with no off smells.

Overall, the best way to qualify matcha is to taste it yourself and evaluate its flavor, color, texture, and scent.