Napa, Calif. -- The recent introduction of sample-size wine bottles for classes, wine club members and trade sampling hit a responsive chord in wineries, but many winemakers have questions about how the bottles are filled and the longevity of the wines packaged in the “nips.” We asked early adopters to explain how they get best use of the new format. Two different formats emerged late last year, both holding 50 ml of wine (about 1.7 oz) in glass mini-bottles.