Food - Drink
The Main Difference Between Flour And Starch
By LAUREN CAHN
Starch is found naturally in grains and tubers, other starchy plant-based foods like legumes, and products such as flour, which is processed from or derived from starch-containing foods. Although flours and starches are related, and can sometimes be used interchangeably in cooking, they aren't the same.
Starch is one component of flour, but flour cannot exist without starch and protein. Both starch and protein are thickeners, but starch has the power of gelatinization, which breaks down molecules and allows them to absorb water; pure starch is a more effective thickener than flour, but the protein in flour adds structure to foods that starch usually cannot.
Protein levels determine how each variety of flour behaves; contrast this with starch, which is not dependent on protein and varies depending purely on its chemical structure. Generally, wheat bread flour contains the least starch and the most protein, leading to chewy baked goods, while low-protein cake flour produces more tender results.
Meanwhile, each kind of starch has its own thickening and gelatinizing powers; potato starch dissolves thoroughly, which makes it fit for sauces, soups, and stews that are meant to be translucent, while tapioca breaks down faster at higher temperatures and is best used in cool liquids. All types of flour and starch are versatile, but serve different purposes.