Holding time refers to the length of time the coffee is allowed to remain in an airpot, or on a burner, and still remain fresh. Even the best coffee will taste bad if it's not fresh. In a glass carafe on the burner, the coffee is at its best for only 15 to 30 minutes. To maintain maximum taste and freshness for a longer period of time, we recommend transferring your brewed coffee immediately into an insulated airpot, where it will remain very fresh for 60 to 90 minutes.