This recipe, because of the old-fashioned technique of adding the syrup to soda water, creates a clone of Coke as it would taste coming out of a fountain machine. That Coke is usually not as fizzy as the bottled stuff. But if you add some ice to a glass of bottled Coke, and them some of this cloned version, the bubbles will settle down and you'll discover how close the two are. You can keep the syrup in a sealed container in the fridge until you are ready to mix each drink with soda water.