Coacervation is the process by which starch retrogrades in bread, contributing to staling. After baking, the gelatinised starch molecules, particularly amylopectin, gradually reassociate and crystallise as the loaf cools and ages, squeezing out water and firming the crumb. The bread tastes dry and tough even though its total moisture has barely changed. Warming refreshes it temporarily by melting the crystals. Commercial bakers retard staling with emulsifiers, enzymes, and packaging that limits moisture migration. Understanding coacervation explains why fresh bread stales fastest at refrigerator temperatures, which accelerate starch crystallisation.