On food and cooking the science and lore of the kitchen ( PDFDrive ) 1482

unless they essentially dehydrate them, since the food surface gets no warmer than the interior Thin, radiation-concentrating metal sheets in special microwavable food packaging can help heat the food surface to the point that it browns Utensil Materials Finally, a brief discussion of the materials from which we make our pots and pans We generally want two basic properties in a utensil Its surface should be chemically unreactive so that it won’t change the taste or edibility of food And it should conduct heat evenly and efficiently, so that local hot spots won’t develop and burn the contents No single material provides both properties The Different Behaviors of Metals and Ceramics As we’ve seen, heat conduction in a solid proceeds either by the movement of energetic electrons, or by vibration in crystal structures A material whose electrons are mobile enough to conduct heat well is also likely to give up those electrons to other atoms at its surface: in other words, good conductors like metals are usually chemically reactive By the same token, inert compounds are poor conductors Ceramics are stable, unreactive mixtures of compounds (magnesium and aluminum oxides, silicon dioxide) whose covalent bonds hold electrons tightly They therefore transmit heat slowly by means of inefficient vibrations If subjected to the direct and intense heat of the stovetop, ceramics can’t distribute the energy evenly Hot areas expand while cooler areas do not, mechanical stresses build up, and the utensil cracks or shatters This is why ceramics are generally used only in the oven, where they encounter only moderate and diffuse heat, or are applied in thin coatings on ... Ceramics are stable, unreactive mixtures of compounds (magnesium and aluminum oxides, silicon dioxide) whose covalent bonds hold electrons tightly They therefore transmit heat slowly by means of inefficient vibrations If subjected to the direct and intense heat of. ..As we’ve seen, heat conduction in a solid proceeds either by the movement of energetic electrons, or by vibration in crystal structures A material whose electrons are mobile enough to conduct heat well is also likely to give up... If subjected to the direct and intense heat of the stovetop, ceramics can’t distribute the energy evenly Hot areas expand while cooler areas do not, mechanical stresses build up, and the utensil cracks or shatters