I am continually talking about using leftover kitchen liquids as sorbet but have not delineated the exact process or fundamental concerns to its preparation. I could devote an entire book chapter to the principles behind ice cream making but here I’ll give you a concise overview.
An ice cream maker is one of those unnecessary kitchen utilities that I find worth the investment. Most stand mixers will sell an ice cream mixing component separately; it is a bowl that you first freeze then fit onto the base, a special paddle stirrer fits onto the top and you apply your liquid mix. Other, stand alone, ice cream makers are sold that do not require the stand mixer but do take up a little more room in the cupboards.
At first glance the process of making ice cream is easy; follow directions to make a flavored liquid mixture and apply it to the mixer per manufacturer’s instructions. However if you plan to explore and improve upon existing recipes the concept behind an ice cream’s texture and flavor should be understood.
The flavor and texture of an ice cream will vary depending on the fat content of the liquid mix. Of course, a higher fat content will give a richer flavor but there must be a balance between liquid water, milk fat, milk protein and sugar to coat and adhere to the ice crystals formed. The addition of sugar not only imparts flavor but changes the physical properties of the liquid mixture; lowering the freezing point which allows some liquid to be trapped between the ice crystal lattice. Basically, the ice crystals form a little package of flavor that bursts onto the taste buds once melted … and the smaller the ice crystals the smoother the package.
The size of the ice crystals is directly proportional to the time it takes the mixture to freeze; a liquid mixture that has been brought to a temperature just above freezing will form very small ice crystals immediately when added to the frozen bowl of the ice cream maker, forming the initial lattice for all other ice crystals to form on. The slower it takes the liquid to come to freezing temperature, the longer it takes the ice crystals to form and thus a larger ice crystal lattice that penetrates the taste buds instead of melting quickly on the tongue.
The liquid mixture described is the simplest mix, known as the Philadelphia style. I use this to make a very simple vanilla bean ice cream by dissolving two-thirds cup sugar in 3 cups of heavy cream with the seeds of one vanilla bean and a teaspoon of vanilla extract. Once it is chilled, I spike it with a quarter cup of cognac before applying it to the ice cream machine.
Another style of ice cream is the French or custard style, aptly named for the inclusion of egg yolk to the liquid mixture that, once heated, emulsifies with the water component allowing a greater liquid content within the crystals. Whichever mixture you choose, once the ice cream maker has agitated the mixture to incorporate enough air and brought it to a decent hardness, remove it to a shallow storage container which exposes more surface and allows it to harden faster.
The same principles described here for ice creams are the same (for the most part) for sorbets with the exclusion of dairy and the addition of acid. The final target content of both sugar and acid in my liquid sorbet mixes are about 30 percent and 0.5 percent respectively to the final volume. I also like to add a complimentary flavor of liqueur to the mix that does not freeze in the final product, giving a good liquid quality (as described for ice creams). I think the best base mix is to make simple syrup of sugar, light corn syrup and water (1/2 cup, 1/2 cup and 3/4 cup). Once chilled, I add in the juice of one lemon, 1 cup of your flavoring, a pinch of salt and 1/4 cup of the liqueur.
Once you have developed a base mix for either an ice cream or sorbet and understand the contributing factors of the ingredients, it will be easy to manipulate existing recipes or to create your own. You’ll become your own kitchen sleuth and be able to present with the utmost confidence.
bobby’s recipe
Vanilla ice cream bombe with raspberry sorbet and lemon curd
The bombe (pronounced bahm) is, traditionally, a layered dessert of ice cream and sorbet or sherbet with a custard center. With the proper planning, the components can be made a few weeks ahead in your home ice cream maker or can be made semi-homemade a la Sandra Lee by purchasing quality sorbet and ice cream while making the lemon curd yourself which is fairly simple. Plan your assembly well as each layer of the bombe will take about an hour to harden.
For the lemon curd
4 large egg yolks
Zest of one lemon
1/4 cup lemon juice
1 tablespoon lemon juice
1-1/2 cups sugar
3 tablespoons of butter
Pinch of salt
In a sauce pan over medium high heat combine the egg yolks, zest of one lemon, lemon juice and sugar. Whisk to combine and continue stirring with a wooden spoon until the mixture has thickened and reached 160 degrees (about 10 minutes). Remove from the heat and stir in butter and salt. Store the curd with a film of cling wrap directly on the surface and chill until ready for use.
Bombe assembly
Serve one bombe per person and make (or purchase) the appropriate amount of ice cream and sorbet. The curd recipe makes one cup, which should be more than enough for at least 12 individual servings.
Line a 6-ounce soufflé cup with enough tin foil that will be able to enclose the final product. Spread softened vanilla ice cream into the soufflé cup so that it fits up the sides and on the bottom and is about 1/8 inch thick. Return the soufflé cups to the freezer and harden the spread vanilla ice cream. Once hard to the touch, spread a layer of raspberry sorbet inside the soufflé cup at about the same thickness and shape one eighth inch below the vanilla ice cream layer. Return to the freezer to harden. Spoon in a tablespoon dollop of the curd right in the center cavity. At this point, all the layers should be flush and the vanilla ice cream has a lip of about one eighth inch above the rest. Allow the curd to harden in the freezer then spread some softened vanilla ice cream on the top to seal the bombe. Fold the aluminum foil up and around the bombe and set back in the freezer to harden.
Serve on an individual plate with some lemon zest and a sprig of mint.