Science: Researchers at the Swiss Federal Institute of Technology in Lausanne have been studying the hydrodynamics of wine swirling, done by connoisseurs to release red wine’s bouquet through mixing and oxygenation. They found that three factors determine whether the wine arcs smoothly or starts to splash: the ratio of the level of wine to the diameter of the glass, the ratio of the diameter of the glass to the width of the circular shaking, and the ratio of the centrifugal and gravitational forces acting on the wine. Their findings, which they presented last week at the annual meeting of the American Physical Society’s division of fluid dynamics in Baltimore, Maryland, could prove useful not only to wine tasters but also to lab technicians who swirl bacterial cultures to distribute nutrients and remove excess carbon dioxide.