On food and cooking the science and lore of the kitchen ( PDFDrive ) 186

proteins must span and knit together — by a factor of 6! And each tablespoon of sugar surrounds every protein molecule in the egg with several thousand sucrose molecules Because the egg proteins are so outnumbered by water and sugar molecules, the coagulation temperature in a custard is between 10 and 20ºF higher than in the undiluted egg, between 175 and 185ºF/79–83ºC And the protein network that does form is tender, tenuous, and fragile Exceed the coagulation range by just 5 or 10ºF and the network begins to collapse, forming water-filled tunnels in the custard, grainy curds in the cream Gentle Heat Many cooks have known the temptation to crank up the heat after a custard has been in the oven for an hour with no sign of setting, or a cream has been stirred and stirred with no sign of thickening But there’s good reason to resist The gentler these dishes are heated, the greater the safety margin between thickening and curdling Turning up the heat is like accelerating on a wet road while you’re looking for an unfamiliar driveway You get to your destination faster, but you may not be able to brake in time to avoid skidding past it Chemical reactions like coagulation develop momentum, and don’t stop the second you turn off the heat If the thickening proceeds too fast, you may not be able to detect and stop it before it overshoots done and hits curdled A curdled cream can often be salvaged by straining out the lumps, but an overcooked custard is a loss Always Add Hot Ingredients to Cold Careful heating is also important during preparation of the mix Most custard and cream mixes are made by scalding milk or cream — quickly heating it just to the boil — and then stirring it into the combined eggs and sugar This technique heats the eggs gently but quickly to 140 or 150ºF, just 30 to 40ºF short of the ... Chemical reactions like coagulation develop momentum, and don’t stop the second you turn off the heat If the thickening proceeds too fast, you may not be able to detect and stop it before it overshoots done... during preparation of the mix Most custard and cream mixes are made by scalding milk or cream — quickly heating it just to the boil — and then stirring it into the combined eggs and sugar This...between thickening and curdling Turning up the heat is like accelerating on a wet road while you’re looking for an unfamiliar driveway You get to your destination faster, but you may not