Nestlé Nesfruta Coconut Pineapple Liquid Flavour Enhancer

My overall rating

I really dislike plain water. I drink a lot more fluid by using this water flavoring all the time. I really like this product but it stains my teeth badly. The only clear one I buy now is coconut pineapple. Yummy. But my teeth are still getting...   +

I really dislike plain water. I drink a lot more fluid by using this water flavoring all the time. I really like this product but it stains my teeth badly. The only clear one I buy now is coconut pineapple. Yummy. But my teeth are still getting stained.
What is in the product to cause this

Also sadly when i drink this first thing in the morning it irritates back of my throat problem due to acid reflux Makes me cough
This is the only good tasting very low calorie drink I can find so i dont use anything else

I dont want to give it up but having to constantly try to remove the stain is so counter productive
Any suggestions    -