What Is Saliva and How Does It Change the Taste of Food?

Saliva mixes with everything we eat and plays a significant role in which foods we like and what happens to them before and after we swallow. Saliva. It's not the kind of thing that comes to mind often. Sure, you may notice it when you smell a juicy ribeye or the lack of it when you're about to give a public speech. But you may be surprised to learn that a seemingly inconsequential thing like spit plays an important role in our health and in the way our food tastes.

What is Saliva?
Saliva is 99 percent water. The remaining 1 percent is made up of "lots of other things," says Guy
Carpenter, professor of oral biology and an oral physiologist at King's College in London, in an email
interview. Those other things include digestive enzymes, uric acid, electrolytes, mucus-forming proteins
and cholesterol. It's also home to more than 700 types of microbes, including germs like bacteria and
fungi.
The actual makeup of our spit varies from person to person. And each person's saliva fluctuates due to
factors such as age, hormonal influences and even stimuli, Carpenter explains.
As is the case with mucus, our bodies are constantly producing saliva. Throughout the course of a day,
your body churns out about 2 to 4 pints (1 to 2 liters) of spit. Most of that saliva production occurs in the
afternoon and tapers off at night when we tuck into bed. We don't completely stop salivating when we
sleep, which explains why some side- or belly-sleepers wake to discover they've drooled on their pillow.
Where Does Saliva Come From?
Saliva is produced in the salivary glands, which are found in the tissues of our mouth. These glands are
made up of clusters of cells called acini, which secrete saliva through a series of collecting ducts and into
the mouth. There are three major pairs of salivary glands:
Parotid glands: The largest of the salivary glands, these glands are located on both sides of your face in
front of your ears. Each one produces about 10 percent of your mouth's saliva.
Submandibular glands: The submandibular glands are the second largest of the three main salivary
glands and are located under the jawbone.
Sublingual glands: These almond-shaped glands lie on the floor of the oral cavity underneath the
tongue. They are the smallest of the salivary glands.
There are also smaller clusters of salivary glands in your upper digestive tract and esophagus. These
secrete saliva with special enzymes that aid in digestion.
What Purpose Does Saliva Serve?
"Saliva's roles cover all the functions of the mouth you can think of," Carpenter says, "including taste,
chew, swallow, smell (aerosol generation), maintenance of mucosal tissue, lubrication of fats,
maintenance of oral microbiome, speech, etc."
That's a mouthful, so let's break it down and discuss some of the important functions saliva plays in our
bodies.
Saliva Helps You Taste Food
Your tastebuds get all the credit for allowing you to taste food. But they'd be practically worthless if not
for saliva, Carpenter says. It's difficult for our tastebuds, which lie in deep channels across our tongue, to
assess dry, lumpy, aroma compounds without a dose of saliva. Skeptical? Dab your tongue dry, then
place one lump each of rock salt and rock sugar on your tongue. It'll be next to impossible to
differentiate between the two lumps without allowing a wave of saliva to wash over them.
Saliva also contains digestive enzymes that help boost a chemical reaction that signals to the brain that
what we are eating is, in fact, nutritious and safe to swallow.