KFC's secret recipe may or may not have been revealed recently, but the science behind why it tastes so good is clear.
Steve Witherly devoted a whole section to KFC in his 2007 book, "Why Humans Like Junk Food." Keep reading to see insights pulled from the book and Business Insider's interview with Witherly:
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High calorie density is intrinsically appealing.
Because humans evolved as foragers, our brains learned to recognize and desire things that pack a lot of calories.
The caloric density scale ranges from 0 for water to 9 for pure fat.
While raw chicken breast without the skin has a caloric density of 1.35, KFC's original chicken breast scores 2.3; the extra crispy version gets a 2.9. The skin by itself scores an intoxicating 5.0.
"Ergo, the chicken is only a vehicle for eating the skin," Witherly wrote.
Salt makes it super delicious.
Humans have evolved to love salty things — a result of our bodies needing sodium to function properly while our sweat glands constantly deplete the supply, according to Witherly.
One KFC original chicken breast contains 1.1 grams of sodium, amounting to a staggering 48% of your recommended daily value.
All told, salt makes up around 1.85% of the weight of the meal. That's right around the ideal level of salt for human enjoyment of dry foods, according to Witherly.
His theory is that it's perfect for us, since a bite of it combined with the saliva in your mouth brings the salt content to approximately the 1% level found in your blood.
MSG supercharges everything.
KFC adds the infamous flavor-booster monosodium glutamate, or MSG, to dozens of items, as detailed on the company website. It also uses foods naturally high in effectively similar free glutamates, like chicken.
MSG enhances salt taste and salt-taste pleasure while also triggering the brothy umami taste.
Although MSG has gotten a bad rap, most scientists agree that it's safe, as no studies have shown that it causes headaches or other supposed negative effects.
Witherly himself likes to use it (combined with salt at a 9:1 ratio) in his home cooking.
See the rest of the story at Business Insider