Starch properties like how it thickens and changes over time depend on the types of molecules it's made of. By studying 10 different starches, scientists found that both amylose and amylopectin molecules work together to determine how starch behaves. Longer amylose chains and shorter amylopectin chains make starch harder to melt and form crystals. More medium to long amylopectin chains make starch thicker when heated. Understanding these molecular structures helps us know how starch works in food and other products.