For years we’ve preserved open bottles of wine either by using the Vacu Vin Wine Saver, an inexpensive ($9.29) pair of rubber stoppers with a pump that sucks the air out of the bottle, or by pouring leftover wine into a smaller bottle or Mason jar to stave off oxidation. But innovative new gadgets promise to keep wine drinkable longer. We tested six tools, including the Vacu Vin, on half-empty bottles of red and white wine, comparing and evaluating the wines’ flavors and drinkability at various time intervals.