onions

Allium cepa, the bulb, appears in six recipes here, and five of them brown it. Abo shalhoob sautés two diced white onions in the beef pan for 5 to 7 minutes until golden. Harrak osbao takes two thin-sliced ones to deep golden and caramelised in 10 to 15 minutes and lifts out half for the garnish. Gazan sayadiya fries one crisp for the top and cooks a second slowly for 20 to 35 minutes until deep brown. The Japanese curry gives two onions, sliced thin, 40 minutes over medium-low heat, until deep amber, and says there is no shortcut. Maqluba takes 5 to 8 minutes for one large onion in rings, soft and lightly browned. In the jameed-free mansaf four quartered onions go in unbrowned with the lamb shanks.

The Journal's note on browning supplies the chemistry. Cooking an onion slowly to deep brown runs two processes at once, the Maillard reaction and caramelisation, and the result tastes like neither alone. Caramelisation is sugar by itself: fructose goes at around 105 degrees, glucose near 150, sucrose around 160 to 170, maltose not until 180. The Maillard side depends on which amino acids are present, part of why browned lamb, onion and bread do not smell alike. It ends in pyrazines, and the library's page on them notes that the Japanese curry builds its base three times, in the onion, the seared beef and the toasting flour.

Water sets the pace. Evaporation holds a wet surface near 100 degrees, below the range where browning moves quickly, and Maillard browning peaks at a water activity of roughly 0.6 to 0.7. The note gives no onion timings, so the ones above are the recipes' own.