To maintain the freshness of your Blackberry Quark Cake, it is important to store it properly. Once cooled, cover the cake with plastic wrap or aluminum foil to prevent it from drying out. Ideally, it should be kept in the refrigerator, where it can last for up to 4 days. If you anticipate a longer storage period, consider freezing it. To freeze, slice the cake into individual portions, wrap them tightly in plastic wrap, and package them in an airtight container or freezer bag. When you’re ready to enjoy it, simply thaw the portions in the refrigerator overnight and allow them to come to room temperature before serving. This method preserves the texture and flavor, keeping your cake delicious even after storage.