Green Apple (Sour) Flavoring

I have tried 3 flavors and so far not happy at all. I have used 1 - 1-1/2 tablespoons just to get flavor. I have sent an email - we will see if they respond to see if I am doing something wrong? But right now I would give the a one star.

My best customer will love that I got sour green apple again

Not too bad, think I need to put more sour drops.