The correct term is peppery – not pepperish.

What is the meaning of word peppery?

1 : of, relating to, or having the qualities of pepper : hot, pungent a peppery taste. 2 : having a hot temper : touchy a peppery boss. 3 : fiery, stinging a peppery satire.

Is peppery a taste?

peppery in Tastes topic

From Longman Dictionary of Contemporary Englishpep‧per‧y /ˈpepəri/ adjective 1 tasting or smelling of pepper2 informal becoming annoyed easily SYN irritableExamples from the Corpuspeppery• Dark green arugula, often used as a stand-alone salad green, has a peppery and slightly bitter flavor.