What came first--the chicken or the egg?
Well, what really matters is that not long after the chicken came along, someone put
that chicken in some batter, threw it in a deep fryer and made one of the most delicious foods EVER.
But what makes this summer picnic staple so darn tasty?
It’s all about the delicate dance of fat at very high temperatures.
In other words, chemistry.
So if mastering the art of fried chicken is on your bucket list, stay tuned for a sizzling
scientific tutorial.
No secret recipe required.
Want to make fried chicken that meets “thigh” expectations?
You’ll need a batch that blends a crispy texture with salty, savory flavors--qualities
this dish owes to the chemistry of frying.
Deep frying means fully dunking your food into piping hot oil.
We’re talking about 150 - 190 C (302 - 374 F).
Most restaurants manage this with an industrial deep-fryer, but you can make tasty fried chicken
at home in a deep ideally cast iron skillet.
After you’ve marinated and battered your chicken, you’ll need to choose a cooking
oil to get started.
Canola, vegetable and peanut oil all work well because they have a neutral flavor and
can reach high temperatures without smoking.
Like all cooking oils, these oils are filled with triglycerides-- big molecules made up
of glycerol and three fatty acid chains.
Triglycerides are the main component of human body fat, so as you might imagine, they don’t
make fried chicken the healthiest picnic food.
But we’re here for flavor, people, not health.
Once the chicken is dunked in the oil, hotter, less dense oil rises and colder, denser oil
sinks to the bottom of your pot or fryer--creating a constant, even circulation of heat at the
surface of the chicken.
That’s called convection.
That heat then diffuses into the center of the chicken to cook the raw meat, otherwise
known as conduction.
After a few seconds, you’ll notice lots of sizzling bubbles at the edge of the meat.
Believe it or not, that’s not boiling oil.
The bubbles are actually made of steam from boiled water leaving the meat.
These rapid-fire bubbles create an important “steam barrier” that blocks the chicken
from absorbing too much oil--which helps maintain the crispy crunch.
During this sizzling stage, three important chemical processes are underway, each with
the power to make or break your country cookout: hydrolysis, oxidation, and polymerization.
Hydrolysis is a type of reaction where a compound is split into fragments by water.
In this case, water released from the chicken reacts with triglycerides in frying oil, splitting
them into free fatty acids and a few other compounds.
This process is crucial in extracting water from fried foods and gives the batter and
skin on fried chicken that amazing crunch.
But as hydrolysis slows down, those free fatty acids will build up in the frying oil.
Just like you want to change your oil in your car every so often, you also want to change
your frying oil to avoid any unpleasant flavors and odors.
You can spot old oil at home by looking out for foaming, smoking, deeper colored oil or
the musty, fishy smell of free fatty acids.
Gross.
Oxygen also reacts with oil during the deep-frying process.
While gently browned fried chicken has a pleasant buttery, nutty flavor, the oxidation of certain
fatty acids, like linolenic acid, can produce volatile compounds.
Volatiles are smelly compounds and can easily go airborne and fly into your nostrils.
These volatiles can rob your chicken of good flavors and aromas in exchange for a fishy scent.
And If I wanted fish I’d be in a video about fish.
Like that one right up in the corner. Right there. See it?
Anyway, to avoid these smelly substances, you should opt for a deep fryer or a deep
pot--basically, anything with a small surface area to volume ratio.
This way, with the chicken totally submerged, less oxygen will reach the goods and allow
for unsavory reactions.
Another tip?
Add some spinach powder or ginseng extract to your batter.
These plants have a; high quantity of antioxidants like vitamins A and C that will help block
the oxidation process.
If you then want to call it, "healthy fried chicken," well, we can't stop you.
While those volatiles make a big impact on overall flavor, the high heat required for
frying can cause fatty acids within the oil to polymerize.
In this process, fatty acids link together to form longer chains of fat.
Polymers.
Delicious, delicious polymers.
Polymerization speeds up the degradation of oil by making it thicker.
Again, degraded oil means gross fried chicken, so keep that oil fresh!
Higher temperatures speed up both oxidation and polymerization, so it's best to not to
wing it. Use a thermometer and make sure your oil temp stays pretty close
to 168 C. But the important part is that it stays consistent throughout the frying.
Also, watch how long you fry.
Under-fried chicken will lack color and crunch and may not cook through, while over-fried
chicken will be too tough, ugly and greasy.
You’ll know you’re done when you start to see very few bubbles left on the surface
of your tender creations.
Fish them out now before excess oil seeps in and let them cool on a rack.
Once you’re well fed, you can sit back on a soft patch of grass in the summer breeze
and get back to all those big chicken-based philosophical questions you've been struggling with.
The egg came first, by the way.
If you liked this round of science-sanctioned cooking advice, check out more tasty tips
on firing up the grill this summer.
Or find out what happens when frying goes very, VERY wrong.
Thumbs up and subscribe on your way out, and hey, thanks for watching.