Check If Your Oven's Temperature Is Accurate With This Sugar Hack — No Thermometer Required!

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An oven that misleads you about what temperature it's heating up to can be incredibly frustrating, from the undercooked dinners to the dried-up desserts. Among all the things we need to know about sugar, one of the most important is the way it tells us our ovens are running correctly. That's right. There's a quick, budget-friendly hack to determine your oven thermometer's accuracy, and all you need is a bit of sugar and aluminum foil.

To start, preheat your oven to 350 degrees Fahrenheit (177 degrees Celsius), and while it's heating up, use the foil to fashion two small vessels and put about a tablespoon of sugar in each one. Once your oven is heated, place one of the foil containers inside and let it bake for about 15 minutes. Remove it from the oven and set it aside for now. Then, turn the heat up to 375 degrees Fahrenheit (190 degrees Celsius) and place your second foil container inside, again baking for 15 minutes. After the timer goes off, take out your second sample and compare it to the first. 

If both are white, your oven is running too cool. If both are brown, your oven is running too hot. However, if your first sample is white and the second is brown, then your oven is running correctly. Although there are more efficient methods to caramelize sugar, this simple hack makes the sugar's reaction to heat a reliable tool to indicate the accuracy of your oven.

The key to this useful little trick is caramelization, the thermal decomposition of sugar, which starts at 340 degrees Fahrenheit (170 degrees Celsius). Yes, that's lower than the temperature of the first test. Unlike other substances, such as water, sugar doesn't have an instant switch. Instead, sucrose (which is what plain white sugar is) has a temperature zone over which the thermal decomposition takes place. But the browning part of caramelization is a function of time and temperature. At 350 degrees, it starts to break down, but it doesn't really have time to start browning. However, at a higher temperature, 375 degrees, 15 minutes is plenty of time to start seeing color. Of course, all this assumes you're using white sugar. Because of the differences between white and brown sugar, such as moisture content, these temperature settings only work with plain white sugar.

If your oven isn't accurate, you don't have to live with it. The easiest way is to call in a professional. Unfortunately, that could cost several hundred dollars. Instead, pull out your oven's trusty user manual and locate the instructions for calibration. At this point, you need to be more accurate than the sugar test, though, so it's time to invest in a standalone oven thermometer if you don't already have one. A simple one like the AcuRite stainless steel oven thermometer costs less than $10 on Amazon. But there's no need to invest in one until you're sure your oven needs calibration. While this test isn't perfect, it does a good enough job to help you determine whether your oven is running too cool, too warm, or just right.