Yes, you can generally leave a buttercream frosted cake out overnight, provided it is properly covered. Buttercream frosting is quite stable at room temperature, making it a suitable choice for cakes that will be enjoyed over several days.
Optimal Storage for Buttercream Cakes
A cake frosted with buttercream can remain safely at room temperature for an extended period, often up to four days, when stored correctly. The key to maintaining its freshness and preventing it from drying out or absorbing external odors is proper coverage.
Why Buttercream is Room Temperature Friendly
Traditional buttercream is typically made from sugar, butter, and sometimes milk or cream. Its high sugar and fat content naturally helps preserve it by inhibiting bacterial growth, making it less susceptible to spoilage at typical room temperatures compared to frostings with high proportions of perishable ingredients.
Best Practices for Overnight Storage
To ensure your buttercream cake remains delicious overnight and beyond, consider these essential tips:
- Keep it Covered: The most crucial step is to protect the cake from air exposure, which can cause it to dry out or become stale.
- Cake Dome: An airtight cake dome is ideal for maintaining humidity and keeping the cake fresh.
- Plastic Wrap: If a dome or airtight carrier isn't available, wrap the cake tightly with plastic wrap, ensuring it creates a good seal around the cake. Try to minimize direct contact with the frosting if possible, or use toothpicks to create a tent.
- Original Box: If the cake came in a sturdy bakery box, you can often store it directly in the box, ensuring the lid is securely closed.
- Room Temperature: Store the cake in a cool, dry place away from direct sunlight, appliances that generate heat, or drafts. Excessive heat can cause buttercream to melt or become greasy. An ideal room temperature is typically between 68-72°F (20-22°C).
- Avoid Odors: Store the cake away from strong-smelling foods, as cakes can absorb odors from their environment.
When Refrigeration is Necessary
While buttercream cakes are typically fine at room temperature, certain scenarios or other frosting types do require refrigeration for food safety and quality:
| Frosting Type | Room Temperature Storage (Covered) | Refrigeration Recommendation |
|---|---|---|
| Buttercream | Up to 4 days | Not strictly necessary for safety unless the cake contains perishable fillings or is in a very warm environment. |
| Cream Cheese | Not recommended | Required due to high dairy content; always refrigerate. |
| Ganache | Not recommended for long periods | Required for longer storage, especially if made with fresh cream. |
| Whipped Cream | Not recommended | Required due to high dairy content; these cakes are highly perishable. |
Note: If your buttercream cake also contains perishable fillings such as fresh fruit, custard, or cream cheese, it should be refrigerated to prevent spoilage of the filling, regardless of the frosting type.
Unfrosted Cakes
For an unfrosted cake, it can typically sit out at room temperature for up to 2 days when properly covered to prevent it from drying out.
By following these guidelines, you can confidently leave your buttercream frosted cake out overnight, knowing it will be just as delightful the next day.
