Make finger-lickin’ chicken
Scientists delve deep into the chemistry of frying
WARM. Battered. Deep-fried. It’s probably the most evil food ever. But it’s also a contender for the most delicious. So exactly what makes the perfect piece of fried chicken? Science found out.
It all about the chemistry of frying.
The American Chemical Society is trying to win the hearts of the public with a greater understanding of the mechanics of the world around them.
How better to do so than through their stomachs? And fried chicken. Turns out, producing the most finger-lickin’ piece is all about the delicate dance of fat at high temperatures.
The heat is on
Crispy. Salty. Savoury.
The ideal piece of fried chicken only comes about if you get the chemistry right.
It’s about getting the meat and the fat to make beautiful music together.
And this happens at a temperature of between 150C and 190C. But 168C has been identified as the ideal.
This can be achieved at home in a deep frying pan – so long as the chicken is almost entirely immersed in the bubbling oil, and an even temperature maintained.
Canola, vegetable and peanut oil work the best. These have neutral flavours and can handle the high temperatures necessary without starting to smoke. Here’s where things start to get deep. Which is why you need a lot of oil.
Steamy dance
Hotter oils at the bottom of the fryer become less dense as the molecules dance about. As the oil at the top cools, its density increases – so it sinks.
This circulates the heat evenly around the chicken, and refreshes the oil in contact with its surface.
Now the dance begins to get steamy.
You’ll see sizzling bubbles emerging from the batter. And no, that’s not boiling oil. It’s actually steam bursting out from the moisture within the chicken itself.
This is important.
And it’s why the oil must be so hot.
The bubbles of steam create a barrier – preventing the batter and meat from absorbing too much of the surrounding oil.
It also dehydrates its edges and aerates the batter, creating that oh-so desirable crispy crunch.
So if your favourite fried food is too greasy and gooey, you know where you’ve gone wrong.
Now you can move your culinary expertise to a new level. Advanced frying Oils are largely made up of molecules called triglycerides. In the molecular world, these are very large beasts which combine a glyceride chain with three fatty acids.
They are also a large part of human body fat ... which we’ll go into denial about for now.
An important part of perfect fried chicken is how these triglycerides behave in a process called hydrolysis. It’s a reaction where water breaks up other compounds.
In frying, hydrolysis (caused by the previously mentioned steam) breaks fatty acids free from the triglycerides in oil.
But those fatty acids will build up and oxidise over time. This is why you will need to change your oil when it begins to thicken, look darker, starts to smoke or foam – or smell fishy.
So the taller your fryer, the less boiling oil comes into contact with the air – and the less oxidisation (and smelly byproduct) results. Another tip is to add some spinach powder or ginseng extract: Their antioxidants will help reduce this oxidisation process.
Golden temptation
So how do you know your fried chicken has been cooked to the point of being put on your plate?
The bubbling will reduce, with only a few appearing on its golden-brown surface.
Leave it in longer and the chicken will toughen and become increasingly oily.
Take it out too soon and it won’t have that magic colour or crunch, and may be undercooked.
It’s the perfect marriage of chicken, batter – and fresh hot oil – that produce the world’s most heavenly snack.
The after-meal guilt, however, is your own problem.