Why do frozen turkeys explode when deep-fried?

Deep-frying a turkey is a good way to get a scrumptious, moist meal for Thanksgiving. However this technique of cooking is usually a very harmful enterprise.

Each fall, tens of millions of {dollars} of injury, journeys to the ER and even deaths consequence from makes an attempt to deep-fry turkeys. The overwhelming majority of those accidents occur as a result of individuals put frozen turkeys into boiling oil. If you’re contemplating deep-frying this yr, don’t forget to thaw and dry your turkey earlier than putting it within the pot. Failure to take action might result in an explosive catastrophe.

What’s so harmful about placing even {a partially} frozen turkey in a deep-fryer?

I’m a chemist who research plant, fungal and animal compounds and have a love of meals chemistry. The rationale frozen turkeys explode, at its core, has to do with variations in density. There’s a distinction in density between oil and water and variations within the density of water between its strong, liquid and gasoline states. When these density variations work together in simply the suitable method, you get an explosion.

Understanding density

Density is how a lot an object weighs given a particular quantity. For instance, think about you held an ice dice in a single hand and a marshmallow within the different. Whereas they’re roughly the identical measurement, the ice dice is heavier: It’s extra dense.

The primary vital density distinction in terms of frying is that water is extra dense than oil. This has to do with how tightly the molecules of every substance pack collectively and the way heavy the atoms are that make up every liquid.

Water molecules are small and pack tightly collectively. Oil molecules are a lot bigger and don’t pack collectively as properly by comparability. Moreover, water consists of oxygen and hydrogen atoms, whereas oils are predominantly carbon and hydrogen. Oxygen is heavier than carbon. Because of this, for instance, one cup of water has extra atoms than one cup of oil, and people people atoms are heavier. Because of this oil floats on prime of water. It’s much less dense.

Whereas totally different supplies have totally different densities, liquids, solids and gases of a single materials can have totally different densities as properly. You observe this each time you place an ice dice in a glass of water: The ice floats to the highest as a result of it’s much less dense than water.

When water absorbs warmth, it adjustments to its gasoline section, steam. Steam occupies 1,700 instances the quantity as the identical variety of liquid water molecules. You observe this impact while you boil water in a tea kettle. The power of increasing gasoline pushes steam out of the kettle by means of the whistle, inflicting the squealing noise.

Frozen turkeys are stuffed with water

Frozen turkeys – or any type of frozen meats, for that matter – comprise a whole lot of ice. Uncooked meat will be anyplace from 56% to 73% water. In case you have ever thawed a frozen piece of meat, you might have in all probability seen all of the liquid that comes out.

For deep-frying, cooking oil is heated to round 350 levels Fahrenheit (175 C). That is a lot hotter than the boiling level of water, which is 212 F (100 C). So when the ice in a frozen turkey is available in contact with the recent oil, the floor ice rapidly turns to steam.

This fast transition just isn’t an issue when it occurs on the very floor of the oil. The steam escapes harmlessly into the air.

Nonetheless, while you submerge a turkey into the oil, the ice contained in the turkey absorbs the warmth and melts, forming liquid water. Right here is the place the density comes into play.

This liquid water is extra dense than the oil, so it falls the underside of the pot. The water molecules proceed to soak up warmth and power and ultimately they modify phases and turn out to be steam. The water molecules then quickly unfold far other than each other and the quantity expands by 1,700 instances. This growth causes the density of the water to drop to a fraction of a p.c of the density of the oil, so the gasoline needs to rapidly rise to the floor.

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Mix the quick change in density along with the growth of quantity and also you get an explosion. The steam expands and rises, blowing the boiling oil out the pot. If that weren’t harmful sufficient, because the displaced oil comes into contact with a burner or flame, it could actually catch fireplace. As soon as some droplets of oil catch on fireplace, the flames will rapidly ignite close by oil molecules, leading to a fast-moving and sometimes catastrophic fireplace.

Yearly, 1000’s of accidents like this occur. So, do you have to resolve to deep-fry a turkey for this yr’s Thanksgiving, you’ll want to totally thaw it and pat it dry. And subsequent time you add a little bit of liquid to an oil-filled pan and find yourself with oil all around the range, you’ll know the science of why.