Line a baking sheet with parchment paper or aluminum foil. Take each jackfruit segment and coat on all sides with the seasoned cornmeal mixture, tap it on the edge of the dish to knock any excess coating loose before placing on baking sheet. Continue this process until all of the jackfruit segments are coated and evenly distributed on the baking sheet. Use a silicone sauce brush to dab a light layer of grapeseed oil on each piece of jackfruit. Flip over and repeat the process until all of the jackfruit segments are evenly coated.