Air bubbles can occur under Frosting Sheets due to several reasons, and 99% of these reasons are related either to storage, application or moisture. If you've ever run into bubbling, chances are, one of these was the culprit.
Here are a few common causes and potential solutions that can help you get to the bottom of your bubbling issue:
Trapped air during application
Air bubbles may form when Frosting Sheets are not properly applied to a cake or surface. If the sheet is not smoothed out carefully, air can become trapped beneath it. To solve this issue, you can try the following steps:
1. Ensure that the surface of the cake is clean, and not too moist before applying the Frosting Sheet.
2. Even out your cake's surface. If the cake's surface is not even, the sheet won't quite be either. Uneven "peaks" in buttercream are a top cause of sneaky air pockets. If the surface you're applying the sheet to is not as flat as possible, the sheet can never really be flat as small pockets of air can find their way.
3. Gently lay the sheet onto the cake and avoid pressing it down forcefully.
4. Smooth out the sheet slowly and evenly using your hands, a plastic scraper or a smoothing tool, starting from the center and working your way outwards to push out any trapped air from under the sheets.
💡 Extra tip for extra careful decorators: After smoothing from the center out, you can use a very small amount of piping gel or a barely-damp brush of water to "tack down" the very outer edge of the sheet, which creates a physical seal that prevents air from creeping back under the edges as the frosting settles.
Moisture content
Excessive moisture on the cake or the Frosting Sheet itself can lead to the formation of air bubbles. If the cake has not completely cooled or if condensation forms on the sheet, it can create air pockets. To mitigate this issue:
1. Try allowing the cake to cool completely before applying the Frosting Sheet.
2. If condensation forms on the sheet, gently blot it with a clean, dry paper towel before applying it to the cake.
3. We don't recommend applying these sheets to high moisture frosting like whipped cream, cream cheese etc. If you mustuse a high moisture frosting, we'd recommend placing the Frosting Sheet as close as you possibly can to serving time. Why? We wouldn't recommend leaving it on these for long durations. These type of frostings' moisture content is significantly higher than that of basic buttercream, and more moisture on the surface equals less stability when it comes to the Frosting Sheets.
Side note: If you need it to last longer, try backing the sheet with a thin layer of chocolate to create a moisture barrier!
💡 Extra tip: If you're big on fondant, we won't knock you for it. If you are familiar with using fondant and you're applying the Frosting Sheet to a buttercream cake, go ahead and roll your image on a thin piece of fondant before applying it. The fondant will support the sheet and act as a wall between the buttercream and the image. Use a bit of water, corn syrup or vodka to adhere the sheet to the fondant. You most likely won't need fondant if you mind everything else mentioned in this guide, but if you just feel more secure and comfortable with it, you're more than welcome to include it in your process.
Improper storage
Incorrect storage conditions can affect the quality of our Frosting Sheets and contribute to the formation of air bubbles. Moisture and temperature fluctuations can impact the sheet's structure. Here are some storage guidelines to follow:
1. Store the Frosting Sheets in a cool, dry place, away from direct sunlight and humidity.
2. Seal the sheets in the zip lock bag it comes with and push out the extra air inside to prevent exposure to moisture.
3. Avoid refrigerating / freezing Frosting sheets as this can introduce condensation as it cools down. We usually recommend letting the cake get to room temperature first before the Frosting Sheets are applied. The change in temperature from the fridge to normal room temperatures will always cause some form of condensation to take place, that's just science. Hence the bubbling that happens occasionally as a result, but that does not have to be the case though. 👇
Popular Techniques to Tackle Bubbling and Refrigeration
While you're scientifically prone to get condensation / bubbling when taking a cake out of the fridge and in the more humid summer months, bakers and cake decorators have their preferences and techniques.
1. Adhering your Frosting Sheets to your cake with some shortening.
2. Grabbing some buttercream, melting it down a little bit so that there's no air bubbles in the buttercream, then brushing that buttercream all the way across the back of your image before placing it on your cake.
💡 Note: If using the "melted buttercream" method, ensure the frosting is cooled back down to a room-temperature fluid state before application; if the frosting is even slightly warm to the touch (around 28-30°C or 82-86°F), the high sugar content of the Frosting Sheet would begin to dissolve on contact. Melted chocolate or a ganache can also be substituted for the melted buttercream method; they both can provide a stable surface.
3. Putting your cakes into a cardboard cake box wrapped in plastic wrap before putting it in the fridge. When it comes time to remove your cake box from the fridge, leave your cake inside the box until it comes back to room temperature and any condensation should hopefully form on the outside of the box instead of the cake that’s inside it. Then unwrap it and proceed.
💡 Note: Wouldn't recommend doing this with cakes that have initially been frozen during the decorating process as that can cause condensation inside the cake box itself and damage the image. Decorate a cake that's not been frozen before and box/wrap it to limit potential issues.
To maximize the effectiveness of the cardboard box method, place a few food-safe silica gel packets or a small bowl of dry white rice inside the box corners (not touching the cake); these act as active agents pulling residual moisture out of the air before the sheet can absorb it as the cake acclimates to room temperature.
