PROBLEM TO BE SOLVED: To provide effervescent drinks improved foam characteristic effectively, raw material liquid improving the foam characteristic of the effervescent drinks effectively, additive agents and methods about these.SOLUTION: A method includes producing second raw material liquid used in production of effervescent drinks by adding supernatant liquid of yeast suspension provided by contacting of yeast and process liquid to first raw material liquid. Furthermore, the method may include producing effervescent drinks from the second raw material liquid.
