How to Tell if Your Cooking Oil is Hot Enough

Deep frying of elder blossoms
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No matter what the cuisine, they all include some dishes that require frying. Whether it's meat, seafood or  vegetables, it all starts out the same way, with a pan of hot oil. It's easy enough to just pour oil into a pan but how do you know when the oil is hot enough? It's obviously easier if you have a kitchen thermometer but, it's possible to get it right without one as well.

The ideal oil temperature for most frying is between 350-365 degrees.

So, without a thermometer, how do you know when your oil is ready to go? There are several possible methods including dropping a kernel of popcorn into the oil or tossing a few drops of water into it. The easiest and safest, method, though, is to stick the end of a wooden spoon into the oil. If you see bubbles form around the wood and they start to float up, your oil is hot enough to cook with. While a drop or two of water will work, oil and water do not mix and you can get a nasty burn if it splashes up at you. So, the wooden utensil method is the safest.

And why does all this matter? Obviously if the oil is too hot, the food will burn on the outside before cooking on the inside. But the more common problem with oil temperature is that it's too low and that causes the food to start absorbing the oil. So, if you've eaten fried food that tasted overly greasy, chances are it was fried at too low a temperature.

As for the type of oil you use, there are certainly plenty of options. Vegetable oil is one of the most commonly used because it has a relatively high smoke point. Also common is canola oil, healthier than vegetable oil because of its lower saturated fat and higher mono unsaturated fat content. It's best for medium frying temperatures, up to about 450 degrees F but that works for most household frying needs.

Likewise, corn and sunflower oils are reasonably healthy and appropriate for medium frying temperatures.

The healthiest of all the oils, olive oil is great for salad dressings and low temperature frying needs. But it has a low smoke point so it's generally not the idea choice for deep frying. For truly high temperature, choose peanut oil for it's high smoke point.

Whatever oil you use, store it at room temperature, in a dry dark place for about a year. Then, after frying, discard the oil by pouring it into a leak-proof container and putting it in the garbage, not down your kitchen sink drain.