egg

Three recipes use egg (Gallus gallus), and the Journal has one note on it. The carbonara takes three, two whole and a yolk, beaten with 25 g each of pecorino and parmigiano and black pepper, then tossed through the hot pasta without stopping until the sauce turns glossy and creamy, never scrambled. The jameed-free mansaf adds one egg to the laban as a stabiliser, and the oat waffles whisk one with milk, melted fat and vanilla.

The note starts from a number nobody had written down. In 2020 two food microbiologists in Brazil, Lopes and Tondo, instrumented a carbonara to see whether raw yolk could carry Salmonella: drained pasta was at 86.0 degrees, and four and a half minutes after the yolk mixture went in the pan was already below 60. They concluded it is not a reliable kill step. For the cook it means the sauce is not held at a temperature but dropped through a window. Yolk figures run from 62 to 65 degrees for an apolipoprotein to unfold up to 75 for a solid gel, so the advice is off the heat, then brisk stirring.

What holds the sauce is not simply lecithin. Yolk's surface activity is dominated by low-density lipoprotein particles about 30 nanometres across, which break down on meeting the oil-water interface and spill their phospholipids and apoproteins across it. The note stops short of calling lecithin a myth: how the credit divides between yolk's lipoprotein fractions is still an open question. It also sides with the Roman rule against cream, since a properly handled yolk already makes the emulsion.