Which ingredient is critical in producing nougat?

In the production of nougat, egg whites are a critical ingredient due to their ability to create a stable and airy meringue. This aeration is essential as it gives nougat its characteristic light and chewy texture. When beaten, egg whites incorporate air and, when combined with the sugar syrup, help to form the nougat's structure. The whipped egg whites stabilize the mixture as it cools, allowing it to hold its shape while remaining soft and chewy. This property not only contributes to the texture but also enhances the overall mouthfeel of the nougat.

While sugar, nuts, and chocolate are also important components of nougat, they serve different roles. Sugar acts primarily as the sweetener and provides texture, while nuts add flavor and crunch, and chocolate may be used for coating but is not essential for the fundamental characteristics of nougat. The role of egg whites is uniquely vital in defining the quality and texture that make nougat distinct.