The complexity of taste

Taste is a multisensory experience in which smell, texture, and pain receptors all play a role in determining how something tastes.  It’s also a complex process that starts with our tongues, where a variety of sensors in taste buds send signals to our brains. The taste buds are located in the bumps you can see on your tongue.

Depending on their location, your tongue’s taste buds vary in their receptivity to the different tastes we can sense: sweet, salty, sour, bitter, savory (umami), and more recently, fat (“oleogustus”). The taste receptors at the back are most sensitive to bitter taste, those at the tip are most sensitive to sweet and savory tastes, and those on the sides are most sensitive to salty and sour tastes. The bumps on the remaining portions of the tongue don’t contain taste buds. Rather, their rough texture aid in gripping food and transferring it down to the esophagus as well as in cleaning our mouths and spreading saliva. Taste buds also reside on the pharynx, larynx, soft palate, and epiglottis (the little flap that keeps food from going into your bronchial tube). 

Signals sent by taste buds go to other organs besides our brains. Taste receptors are also found in the gastrointestinal tract, liver, pancreas, fat cells, muscle cells, thyroid, and lungs. Receptors in these organs pick up the presence of various molecules, metabolize them, and use them to prepare the organs for work. For example, when your gut notices sugar in food, it tells your brain to alert other organs to get ready for digestion. Taste wakes up the stomach, stimulates salivation, and sends a little insulin into the blood, which in turn transports sugars into the cells.

In 1904 Ivan Pavlov showed that lumps of meat placed directly into a hole in a dog’s stomach would not be digested unless he dusted the dog’s tongue with some dried meat powder to start things off. Looks like he was onto something.

I don’t know what we can do with this information. I just thought it was interesting.

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