Science Says That Whole Eggs Lead To A Denser Swiss Buttercream
Swiss buttercream is typically made with just five ingredients: egg whites, sugar, butter, vanilla, and salt. By using the egg whites, the result is a consistency that is super light and airy. So what should you do if you want a buttercream that is more dense in consistency? The answer is simple: use whole eggs instead of just the egg whites.
The reason all comes down to science — the buttercream becomes denser because the inclusion of the yolks allow for less air to be trapped into the mixture, as it would with just the egg whites. Thus, the Swiss buttercream gains a dense and creamy consistency — although, technically, with the inclusion of whole eggs, it becomes a French buttercream.
For those curious, if you were to take the third and final route — using just egg yolks — then the consistency would be rich and silky, but with a taste that is a bit more custard-like than the simple sweetness of the typical route. Really, all three options will make for a great topping for any cake or cupcake, so it all comes down to personal preference.
What to know about switching up — and storing — Swiss buttercream
Once you've decided what consistency you like best, you may want to start experimenting with recipes and figuring out ways to upgrade the Swiss buttercream. For example, maybe you want to flavor your buttercream — perhaps you want chocolate Swiss buttercream to pair with chocolate cupcakes. For chocolate buttercream, you can melt about one cup of chopped chocolate and cool to room temperature, then mix with the butter before continuing the instructions normally. For a fruit-flavored Swiss buttercream, such as strawberry or blueberry, add two tablespoons of a purée to the finished buttercream.
Or, maybe you don't want to add extra flavor but you do want to add a fun color to the frosting for decoration — luckily, you can use food dye. To avoid adding more liquid to the frosting — and changing the consistency — gel food coloring is the best option. To add the gel food coloring, simply beat the frosting on low as you add it in.
Swiss buttercream can even be made ahead, then stored for later use, so you can focus all of your energy on making the best buttercream possible (then make the cake or cupcakes on a later day). Swiss buttercream can be stored at room temperature for two days, in the fridge for five days, or in the freezer for three months. When you need it, thaw to room temperature, then use a stand mixer to beat for a couple minutes to regain consistency.