You’ll want to read this interview with Nova carefully. Not only does she explain the science behind using different wine glass shapes, she also reveals why some wine tasters hold the glass by the base and what purpose nucleation serves in a sparkling wine glass. (And, yes, she explains what nucleation is, too.)

• The base: The base quite possibly is the easiest of all the parts to understand. It makes sure the glass doesn’t tip over. Don’t cry over spilt milk but spilt wine is another story.
• The stem: The stem serves two distinct purposes. The first is to allow the drinker to hold the glass without touching the bowl. If you hold a wine glass by the bowl you risk heating the wine from your body temperature. It’s not ideal, especially for wines that need to be served cool or cold. If you feel your wine is too cold, cupping the bowl is the most effective way to warm the wine up.The second is holding the glass by the stem will keep the drinker’s hands away from the rim of the glass. Our hands have their own unique scent which most of the time is increased in intensity through the use of fragrant soaps, lotions and perfumes. These scents can overpower, mask or change the aromas from the wine so the design of the stem allows these scents to stay as far away from the drinker’s nose as possible while still allowing for adequate control of the glass. Some professionals even go as far as to hold the base rather than the stem for this reason.