The transformation of the starch causes undesirable firmness in the croissant. Additionally, the formation of the crystal structure of amylopectin requires the incorporation of water. Starch retrogradation actively draws water from the amorphous gluten network and some of the amorphous starch fraction, which reduces the plasticity of both. Water migration influences the quality of stored croissants through two mechanisms. First, as previously stated, water redistributes from gluten to starch as a result of starch retrogradation. Secondly, during the baking process, a moisture gradient was introduced as a result of heat transfer from the oven to the croissant. In fresh croissants, there is high moisture content on the inside and low moisture content on the outside. During storage, this moisture gradient induces water migration from the inside to the outer crust. On a molecular level, water is lost from the amorphous starch fraction and gluten network. At the same time, water diffuses from the outer crust to the environment, which has less moisture. The result of this redistribution of water is a firming up of the croissant, caused by a decrease in starch plasticity and an increase in gluten network rigidity. Due to the presence of large pores in croissants, moisture is lost to the environment at a faster rate than bread products. As such, croissants generally become harder in texture at a faster rate than breads. Fat also affects the quality of croissants in storage. On one hand, an increased amount of in-dough fat has been found to correspond to a reduction in crumb hardness immediately after baking. This is likely attributed to the high-fat content of croissants, as increased fat levels decrease moisture diffusion. On the other hand, although roll-in fat softens the croissant’s initial crumb, its effect on croissant hardness during storage is still unclear.