This Temperature Mistake Will Ruin Your Beer-Battered Onion Rings
It is a universally acknowledged truth that a cook in possession of both onions and beer may want to make beer-battered onion rings. Well, okay, it is necessary to scrounge up a few more ingredients first, since you'll also need eggs, flour, and salt to make up the batter, as well as a quart or two of oil for frying. (Here's a money-saving tip: It's perfectly okay to reuse frying oil a few times.) Even once you've assembled your ingredients, you may need to wait a bit longer to make the batter if your beer is warm.
As long as the beer is cold, it doesn't really matter what kind you use for your onion ring batter — a cheap domestic lager will work just as well as an imported pilsner or stout, and non-alcoholic beers make a refreshing contrast to boozier beverages. (You might want to avoid using an IPA, though, unless you want your batter to be bitter.) The beer really ought to come straight out of the refrigerator, though, since the chilly liquid will keep the gluten in the flour from developing and too much gluten means tough, chewy onion rings. Even though the beer does need to be cold to make the best batter, it's okay if it's flat since bubble-free beer can still make the rings fry up light and crispy.
The temperature of the oil also makes a difference
Of course, the beer isn't the only ingredient where the temperature matters. With deep-fried onion rings — or with any deep-fried foods, for that matter — proper oil temperature is crucial. In fact, one of the biggest mistakes everyone makes when deep-frying is to let the oil get too hot. So be aware that 375 degrees Fahrenheit is best for onion rings, and a higher temperature could result in having the batter burn while your onions remain uncooked. Even worse, if the oil gets too hot, it might even burst into flames, which is a situation best avoided at all costs.
Of course, frying your onion rings at too low a temperature, while less hazardous, is also not optimal. If the temperature dips below about 350 degrees Fahrenheit, then the food will take longer to cook, which will in turn allow the batter to absorb more of the oil. This leads to greasy, soggy rings, which are a sad waste of both beer and onions. To keep the temperature from dropping, it'll help to fry small batches of rings at a time since a too-crowded pan will cool off the oil. You'll also need to use a deep-fry thermometer of some sort to keep the oil temperature in the safe zone. The USDA also recommends keeping a fire extinguisher on hand in case the oil overheats to the point where it becomes dangerous or splashes onto the heating element.