Earlier quoted context omitted.
Glass is amazing. You haven't tasted a beverage until you had it in a glass cup or bottle.
Neither glass nor plastic add or detract from the flavour of a beverage.
Drink a soda from a can and then the same kind from a glass? Night and day. Try experimenting with spoons to eat: wooden, plastic, different metals. You really notice that, or you should: the spoon goes right on your tongue to introduce the food.