On food and cooking the science and lore of the kitchen ( PDFDrive ) 1532

bond once it’s formed When the atoms in a molecule are heated up so they move with the same kinetic energy that they had released when they bonded to each other, then those bonds begin to break apart, and the molecule begins to react and change The strong covalent bonds typical of our major food molecules — proteins, carbohydrates, fats — are broken by about 100 times the average kinetic energy of molecules at room temperature This means that they break very rarely at room temperature, and don’t change at a significant rate until we heat them The weaker, temporary hydrogen and van der Waals bonds between molecules are constantly being broken and re-formed at room temperature, and this welter of activity increases as the temperature rises This is why fats melt and become thinner in consistency as we heat them: the energy of their motion increasingly overpowers the forces attracting them to each other The Phases of Matter In our everyday life, we encounter matter in three different states, or phases (the word comes from the Greek for “appearance” or “manifestation”) These states are the solid phase, the liquid phase, and the gas phase The temperatures at which a material melts — changes from solid to liquid — and boils — changes from liquid to gas — are determined by the bonding forces among the atoms or molecules The stronger the bonds, the more energy needed to overcome them, and so the higher the temperature at which the material shifts from one phase to another During that shift, all the heat added to the material goes into completing the phase change The temperature of a solid-liquid mix will remain fairly constant until all the solid has melted Similarly, the temperature of a pot of boiling ... by the bonding forces among the atoms or molecules The stronger the bonds, the more energy needed to overcome them, and so the higher the temperature at which the material shifts from one phase to another During that...other The Phases of Matter In our everyday life, we encounter matter in three different states, or phases (the word comes from the Greek for “appearance” or “manifestation”) These states are the solid... shift, all the heat added to the material goes into completing the phase change The temperature of a solid-liquid mix will remain fairly constant until all the solid has melted Similarly, the temperature of a pot of boiling