Every chef needs to have a few “go-to” desserts in his or her repertoire, and none is more important than chocolate mousse. The versatility of this preparation is enormous, as chocolate mousse on its own can fill a need for the simplest bistrostyle dessert, while the same recipe could also be turned into a layer in the most sophisticated glazed entremet. An understanding of the basic techniques involved in preparing it will help ensure success with each attempt and eliminate the possibility for mistakes.
The list of ingredients for chocolate mousse is pretty straightforward—chocolate, eggs, sugar and heavy cream. You will also occasionally find additional ingredients in the form of flavorings, butter, gelatin, etc. Recipes vary dramatically, often with respect to the method by which the eggs are treated, but all involve melted chocolate and softly whipped cream. Regardless of the method you use, the ingredients in your recipe perform specific functions pertaining to flavor, texture and stability.
Let’s take a look at the role of each.
Flavor and Stability: The Chocolate
First, you will want to start with a high-quality chocolate. The chocolate in your recipe is responsible for flavor, of course, but also for the stability of the mousse. More specifically, it’s the cocoa solids in the chocolate that provide the flavor, while the cocoa butter provides the stability. Brand name doesn’t matter, but you want to use a pure chocolate with great flavor. Don’t be seduced by “cocoa percentages,” as they don’t necessarily tell you much about the quality of the chocolate; it’s always better to let your palate be your guide. It is true that chocolates with a greater amount of cocoa butter will set firmer than ones with less, and consequently the texture of a mousse made from these different chocolates could vary somewhat. Of equal importance— you really can’t substitute white or milk chocolate into a recipe that calls for dark chocolate—they contain much more sugar, plus dry milk powder, and because of this will not set firm enough. If you decide you want to use white or milk chocolate, look for a recipe specifically designed for them.
Emulsion and Texture: The Eggs
Eggs provide emulsifying properties to chocolate mousse, as well as contribute to its texture. They are frequently separated, with their yolks being cooked into a custard cream sauce or perhaps whipped with sugar into a thick sabayon. Egg whites are commonly aerated into a frothy meringue (see sidebar). It’s smart to choose pre-pasteurized eggs to eliminate the possibilities for contamination. Either way, treat your eggs with care to ensure that the yolks don’t get overcooked, and whip the whites cautiously to be certain they don’t dry out.
Texture: The Cream
Ask anyone to describe a chocolate mousse and they will generally answer with a texture adjective—“fluffy” or “airy”—that’s the result of the cream. Heavy cream is whipped to increase its volume and here many chefs do themselves a disservice by over whipping, leading to a denser finished product. I always inform my students regarding the cream in mousse, “If it’s not pourable, it’s deplorable.” Properly whipped cream will be aerated, but still remain fluid enough to pour into the chocolate base. Moreover, the temperature of the chocolate at this juncture is of critical importance—too hot and the cream will deflate, leading to a dense mousse (to say nothing of a decreased yield). Too cold, and the agitation of the cream will cause the mousse to break. If the chocolate base is between 95° to 105°F, you will experience neither of these setbacks, but be rewarded with a perfectly textured finished product.
Mind Your Meringue
There are many ways to prepare meringue, and although the recipe included here does not include a meringue component, it’s still a good idea to review the method in case you choose a different one. Here are the steps to follow to ensure a quality finished product that balances aeration with stability.
- Choose clean (no yolk), room-temperature egg whites.
- Whip whites by themselves until frothy and opaque.
- Gradually add the sugar “like a fine spring rain.”
- Whip the meringue on a medium speed until the finished product is creamy and resembles shaving cream.
- Meringues with a higher sugar content (up to equal the weight of the egg whites) will be more stable than those with less sugar.
A good habit to develop is “critically” reading a recipe before starting it, to determine in advance whether the meringue will be stable or not. With low-sugar meringues, it’s important to exhibit greater care not to over whip the whites or you will wind up with lots of small “cotton balls” that are impossible to blend into the base.