Participates in the biosynthesis of capsaicinoids in pungent cultivars of Capsicum frutescens. Capsaicinoids, the alkaloids responsible for the heat or pungency of chili pepper, are synthesized from phenylpropanoid intermediates in the placental tissue of chili peper fruit. Can transfer an acyl from 8-methylnon-6-enoyl-CoA to vanillylamine forming capsaicin and CoA. (6E)-8-methylnon-6-enoyl-CoA + vanillylamine = capsaicin + CoA + H(+) Belongs to the plant acyltransferase family.