Wednesday, August 08, 2012
article at Slate reminds me a little of an argument I once had some
years ago with a couple of acquaintances over measurement. The title and
subtitle fairly well sum the article up and mirror the position I took
(although we were not discussing baking): "Ignore Your Oven Dial: You
can't control the temperature of your oven very well, so stop worrying
about it." It is possible that I did not state my position well, but I was
surprised to find myself accused of being some kind of unthinking champion of
ignorance. In any event, the article has interesting things to say about the
problem of knowing what the temperature of an oven is, as well as a perfectly
appropriate way to deal with the problem.
You'd be forgiven for thinking that 350 on the dial means 350 in the oven. You'd be wrong, though. When you set an oven to 350 degrees, there isn't a single spot inside of it that stays at 350 degrees for the duration of a bake session. The modern gas or electric oven has an automatic thermostat that, by design, lets the temperature drop a predetermined number of degrees below your chosen temperature before switching the heat on. The heat then surges the oven well past the desired temperature before shutting off again. A 350-degree residential oven is designed to stay between around 330 and 370 degrees--and that's if it's well-calibrated, which few ovens are. And that's just at the location of the internal thermostat--the rest of the oven is a different story. Every oven has hot and cool spots so difficult to predict that oven design has become something of a mystical pursuit.It's hard to control the temperature, and it is being measured in only one or a few places anyway. The appropriate way to respond is to admit that there is a problem, ditch the silly myth that our post- World War II temperature dials give us precise control over our ovens, and use the cruder, traditional and qualitatively different levels of oven heating that actually make a difference.
Mark Bittman, New York Times food columnist and author of How To Cook Everything ... agrees that "[numerical] oven temperatures are a convention."This is not to say that technology won't ever allow us to regulate oven temperatures much more precisely and evenly, but it does expose five degree increments in oven heat controllers to be more than a little bit silly.
"I tend to think of oven temperatures in maybe four ranges," Bittman says. "[R]eally low, under 275 degrees; moderate, between 275 and 350; high, over 350 but under, say 425; and maximum. But I don't think about those numbers ... I just think 'what am I trying to do here? Blast this stuff or treat it gently, or something in between?' "[links dropped]
Baking by range admits ignorance caused by inadequate means of knowledge. There is no shame in that. In fact, that is actually a better homage to the science that won World War II than aping it with "cargo cult" temperature controls and readouts.