Store all dessert wines around 55 degrees with a humidity level of about 70%, and keep the bottles in a dark location. Once you open your bottle of sparkling or lightly sweet dessert wine, keep it in the refrigerator and use it within 5-10 days. Richly sweet dessert wines, as well as fortified wines, have a high alcohol content and when stored properly can age for up to 50 years. Once you open high-alcohol dessert wines such as richly sweet or fortified wine, they'll last for several months when stored properly. Sweet red wines can keep for several years, but once opened last up to three weeks in the refrigerator.