The bitter truth about sweet onions
There seems to be a bitter fight brewing over sweet caramelized onions. Wednesday morning on Slate, writer Tom Scocca works himself into a lather taking what he calls the Recipe Writing Guild to task for what he calls “lying” about how long it takes to cook onions.
Even as a fully paid up member of that shadowy group, I certainly see where he’s coming from. Apparently some have been claiming that it can be done in 10 minutes or less. You might be able to get something approaching brown in 10 minutes (you’d have to be sure to watch them like a wooden-spoon-wielding hawk to keep from scorching them at that high a temperature), but caramelizing is another thing and it takes far longer.
Part of the issue might be that some recipe writers seem to conflate “browning” and “caramelizing” in some of the instances Scocca cites. Particularly with onions, those are two distinct things. Related, certainly, but not the same.
You can brown onions by cooking them over medium-high heat for 10 minutes or so. They will turn color, probably a light golden brown by that time, but they will still be slightly crisp and taste like onions. Not that that’s a bad thing, in fact, sometimes that’s exactly what you want.
In fact, as an initial step in cooking a dish, it probably is. Caramelization is something else. It’s turning onions into flavor bombs. If you’re not careful, they’ll take over a dish. Think of the flavor of a French onion soup. Truly caramelized onions need to be the star of a dish, not just a flavoring.
In order to bring out the full flavor of caramelized onions, you need to cook them slowly enough that the cells of the onion collapse, mingling their chemical constituents to create a much deeper flavor. At the same time, those cells release their moisture so it can be evaporated, allowing the onions to reach higher temperatures and even more complex flavors.
This is where the real fun begins –- caramelization and, at the same time, our old friend the Maillard reaction. These, too, are frequently confused, but are different things. Caramelization is the breakdown and browning of sugars; the Maillard reaction (which flavors things as different as the brown crust on bread and the brown skin on chicken), is similar, but involves not only sugars, but also enzymes and proteins.
If you want a full explanation of what happens, I can’t think of a better description than the ever-reliable J. Kenji Alt’s piece at Serious Eats.
Alt claims to be able to produce fully flavored caramelized onions in 45 minutes. I am somewhat skeptical, but I trust him enough to give him the benefit of the doubt. When I first started caramelizing onions, it took about two hours. Today I find that it takes about four. I don’t know whether it’s the onions that have changed or me, but in his “Bouchon” cookbook, God, er, Thomas Keller, cites the same timing.
I’m not sure whether it’s wishful thinking on the part of those recipe writers, or simply sloppy description, but I’m with Scocca in calling bull on it.
Photo: What remains of five pounds of onions after caramelizing. Credit: Mel Melcon / Los Angeles Times