On food and cooking the science and lore of the kitchen ( PDFDrive ) 150

long If the hen has mated in recent days, there will be sperm stored in a “nest” at the upper end of the oviduct, and one will fuse with the egg cell Fertilized or not — and most eggs are not — the yolk spends two to three hours slowly passing down the upper end of the oviduct Protein-secreting cells in the oviduct lining add a thickening layer to its membrane, and then coat it with about half the final volume of the egg white, or albumen (from the Latin albus, meaning “white”) They apply this portion of albumen in four layers that are alternately thick and thin in consistency The first thick layer of albumen protein is twisted by spiraling grooves in the oviduct wall to form the chalazae (from the Greek for “small lump,” “hailstone”), two dense, slightly elastic cords which anchor the yolk to the ends of the shell and allow it to rotate while suspending it in the middle of the egg This system keeps as much cushioning albumen as possible between the embryo and the shell, and prevents premature contact between shell and embryo, which could distort the embryo’s development Membranes, Water, and Shell Once the albumen proteins have been applied to the yolk, it spends an hour in the next section of the oviduct being loosely enclosed in two tough, antimicrobial protein membranes that are attached to each other everywhere except for one end, where the air pocket will later develop to supply the hatching chick with its first gulps of air Then comes a long stretch — 19 or 20 hours — in the 2-inch-/5-cm-long uterus, or shell gland For five hours, cells in the uterus wall pump water and salts through the membranes and into the albumen and “plump” the egg to its full volume When the membranes are taut, the uterine lining secretes calcium carbonate and protein to form the shell, a process that takes about 14 ...albumen as possible between the embryo and the shell, and prevents premature contact between shell and embryo, which could distort the embryo’s development Membranes, Water, and Shell Once the albumen proteins... For five hours, cells in the uterus wall pump water and salts through the membranes and into the albumen and “plump” the egg to its full volume When the membranes are taut, the uterine lining secretes calcium carbonate... where the air pocket will later develop to supply the hatching chick with its first gulps of air Then comes a long stretch — 19 or 20 hours — in the 2-inch-/5-cm-long uterus, or shell gland For five hours, cells in