Although significant relationships between WPC and margarine addition were not identified, strong and moderately negative correlations were detected, respectively, between the thickness (r ¼ 0.76) and specific volume (r ¼ 0.66) with the expansion factor (Table 2). Thus, the lower the thickness and specific volume values, the higher the expansion factor. The diameter and thickness ratio (expansion factor) of cookies is primarily physical and is related to the aforementioned capacity of ingredients to absorb water. The specific volume is affected by the treatments used during processing and the quality of the ingredients used in the formulation of the dough, especially flour. According to Table 2, there was no correlation between the yield and the weight of the cookies developed in this study.