The Scientific Secrets Behind Your Favorite Foods

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Credit Jessica Harrop / WGBH

David Pogue and Chris Kimball make scientifically accurate mashed potatoes at America's Test Kitchen

Consider the chocolate bar. The texture, the smell, the flavors that come together in your mouth. Researchers have been hard at work unlocking exactly what makes food like chocolate so delicious, so eventually we'll be able to enjoy sweets and treats more without weighing more.

NOVA ScienceNOW host David Pogue spoke with scientists who are taking food into the laboratory to find out what specifically makes things salty, sweet or bitter. Pogue shared what he learned with Boston Public Radio's Kara Miller.

Why do we cook?

While working on the latest feature from NOVA, "Can I Eat That?" Pogue said he found out that humans are the only animals that cook because we have to cook. If people were on a complete raw diet, humans would die off: we would not be able to retain weight or reproduce. 

"Our ancestors spent so much time and energy chewing — hours and hours a day chewing — that [they couldn't] ever get ahead calorically," he said. 

Cooking had an evolutionary purpose as well. It gave rise to physical changes in our body. If you compare human teeth to the teeth of great apes, human teeth are less fang-like, and their jaw muscles smaller, Pogue said. Human abdomens are also smaller, as humans can get by on less food because they are able to digest cooked food more efficiently.

Designing food

The modern chemical industry has fundamentally changed the way we cook and taste. Pogue visited a food design company in California, where he had the chance to learn about the science behind the recipes that are developed for commercial food chains. The day Pogue was at the food design company, they were experimenting with which chemical they could put into food that would make it smell like Mexican food. Pogue smelled vials that had chemicals in them that not add flavor, but give it the scent of Mexican food.

"I was really offended by that at first, but they pointed out that all cooking, all recipes, are a matter of mixing together chemicals," he said.

There are different sets of chemicals in the average kitchen than in the corporate kitchens, but things like vanilla and yeast are just chemicals.

The perception of taste

Have you heard the adage that 90 percent of taste is smell? Pogue says that's "bologna."

Smell is a component of taste — but flavors go to the back of your mouth, not through your nostrils. When food scientists refer to "flavor" they mean the entire experience of smell and taste.  Your tongue has tiny papillae on it, and each papillae has between six and 60 taste buds. Everyone has a different number of taste buds, and people who experience flavor more intensely, a.k.a. "supertasters," generally have more taste buds.

Consider, also, that we use all five senses to experience food. Pogue said he closed his eyes and could differentiate the sound of hot water from the sound of cold water. Scientists gave him a glass of juice that looked like orange juice, but was really apple juice. When he was asked to identify the juice he tasted, he could not recognize that it was apple. He was also given a jelly bean and asked to hold his nose while he ate it. He could not identify the flavor of the tangerine jelly bean until he unplugged his nose.

The perfect turkey

At America's Test Kitchen in Brookline, Mass., dozens of professional cooks spend all day testing slight variations in recipes with the goal of formulating the best recipes. Pogue visited the kitchen and asked them about the best way to cook a Thanksgiving turkey.

"They can tell you with certainty that brining your turkey overnight in a bucket of salt water is the key," Pogue said.

And don't eat it raw.

Watch a clip from Can I Eat That? below. The full episode airs on WGBH 2 on Oct. 31.