Monday, March 29, 2010
Pavlova is deceiving. It appears to be an easy, fool-proof recipe, but it’s all a disguise. There’s actually quite a bit of science that goes into making it. In general, Pavlova is made by beating egg whites with vinegar until soft-to-stiff peaks form. Sugar is then added gradually until it forms very stiff peaks. Corn starch and flavorings are gently folded into the egg whites before slowly baking at a low temperature to dry out the surface. The critical stage in this process is when sugar is added to the beaten egg whites. This determines the texture of the final product.
First, it is important to understand how foams work. Proteins are the molecules in egg whites that create a foam structure by forming a network around air bubbles. Upon physical stress, such as whipping or beating, proteins undergo transformations that allow them to bind together and arrange themselves around air bubbles. To make meringue, sugar is added to beaten egg whites at different stages to stabilize the foam. Basically, the earlier the sugar is added, the denser the meringue and the longer it will take to reach optimal volume. Sugar added relatively early in the beating process will hinder protein transformations and arrangements at the interface between air and water, thereby preventing the formation of large air bubbles. There are three main culinary terms that are used to describe stages of foam development:
Soft peaks – refers to glossy foam edges that keep some shape but droop once lifted.
Stiff peaks – refers to glossy and defined foam edges that hold their shape. Peaks stand up straight once lifted.
Dry peaks – refers to a dull and firm foam that appears lumpy and crumbly. This is commonly used to make very soft-textured, frothy meringue.
In this recipe, to create a dense-textured, marshmallowy interior, I gradually beat sugar into egg whites at or just before they form soft peaks so that it creates a syrup that tightens the foam. Vigorous beating for about 3 minutes is necessary to evenly distribute the sugar and further divide air bubbles. This also serves to increase volume and stiffen the foam so that it can be shaped onto the parchment. This Pavlova will spread slightly during baking and the result will be a dense, sponge-like consistency. The addition of corn starch also serves to retain moisture and produce a soft center. The fairly high sugar level provides body and helps to create a crispy outer shell. This recipe truly bestows a gastronomic experience of perfectly contrasting textures.
To make the topping, gently toss together strawberries, balsamic vinegar and sugar in a large bowl. Refrigerate 15 minutes. Meanwhile, stir together cream and vanilla extract in a medium bowl. Beat until stiff peaks form using an electric mixer. Place cooled meringue on flat serving platter. Spread whipped cream into the well in the center of the Pavlova and top with macerated strawberries.