Thanks for playing our game! We definitely wanted to integrate the ingredient properties (scent, color, shape) deeper into the game with something like an in game notebook/tips book but we ran out of time.
We did also want to add a trash can to throw away extra materials, but we also didn't have time for that. I think right now you can drag them to the edges of the screen (particularly the bottom of the left half of the screen) and the objects may clip out of the colliders which gives you more space but doesn't actually properly delete them.