Calcium oxide (CaO), commonly known as quicklime or burnt lime, is a widely used chemical compound. It is a white, caustic, alkaline, crystalline solid at room temperature. The broadly used term "lime" connotes calcium-containing inorganic materials, in which carbonates, oxides and hydroxides of calcium, silicon, magnesium, aluminium, and iron predominate. By contrast, quicklime specifically applies to the single chemical compound calcium oxide. Calcium oxide that survives processing without reacting in building products such as cement is called free lime. The major use of quicklime is in the basic oxygen steelmaking (BOS) process. Its usage varies from about 30 to 50 kilograms (65–110 lb) per ton of steel. The quicklime neutralizes the acidic oxides, SiO2, Al2O3, and Fe2O3, to produce a basic molten slag. Ground quicklime is used in the production of aerated concrete blocks, with densities of ca. 0.6–1.0 g/cm3 (9.8–16.4 g/cu in). https://en.m.wikipedia.org/wiki/Calcium_oxide Flour contains a high proportion of starches, which are a subset of complex carbohydrates also known as polysaccharides. The kinds of flour used in cooking include all-purpose flour (known as plain outside North America), self-rising flour, and cake flour including bleached flour. The higher the protein content the harder and stronger the flour, and the more it will produce crusty or chewy breads. The lower the protein the softer the flour, which is better for cakes, cookies, and pie crusts. Some other chemicals used as flour treatment agents to modify color and baking properties include: Chlorine dioxide (unstable to be transported in the U.S.) Calcium peroxide Calcium peroxide Calcium peroxide or calcium dioxide is the inorganic compound with the formula CaO2. It is the peroxide (O22−) salt of Ca2+. Commercial samples can be yellowish, but the pure compound is white. It is almost insoluble in water. https://en.m.wikipedia.org/wiki/Calcium_peroxide As a solid, it is relatively stable against decomposition. In contact with water however it hydrolyzes with release of oxygen. Upon treatment with acid, it forms hydrogen peroxide. Or flatulence. Using flour to make a brick... like how they might have in old Egyptian days. They didn't have cement so how are all those huge monuments still standing upright? The ruling class might have shouted, 'feed them the powder,' if being upsetted. Who would know? Without the germ of the grain still attached, it is as chaff. So yes, even chaff is useful. The meal of oats. Oatmeal... chaff or germ? Additives can cause a food to meet rda.