I used to work for a bottled iced tea company. Every big batch of every flavor was extensively tested by our quality control manager, but I don't believe taste testing was a mandatory part of the process (I could be wrong though). But taste testing IS a vital part of the process for product development. Our test kitchen was in the office so sometimes us staff members got to taste new flavors in development and give feedback. We also had a big vending machine stocked with free iced tea. The daily access to free iced tea was pretty awesome, but the lines for the bathroom not so much.