What exactly do cats taste? Some people swear their cats have a “sweet tooth” due to their fascination with ice cream and other such treats. Some people think cats don’t taste much of anything at all. But the fact is that your cat’s sense of taste is far more refined and specific than we had ever thought. Read on to get the 411 on the flavors felines fancy.
The fact that cats have a measly 470 or so taste buds on their tongues — as compared to the human tongue, which has about 9,000 — had formerly led scientists to believe that cats’ sense of taste was very limited. But recent research has disproved this notion. First of all, your cat’s sense of smell and an additional organ called the Jacobson’s organ provide a whole array of other taste input. According to cathealth.com, “Odors are inhaled to the tongue, the lip is slightly curled, and the tongue is rubbed on the roof of the mouth. Then the mouth, nose, and Jacobson’s organ in some way allow the animal to sense the essence of the flavor and scent in a way that we do not have the capacity to experience.”
A recent study published in the journal PLOS One revealed that cats have 12 different receptors in their tongues for bitter taste, at least seven of which are highly active. It was once thought that obligate carnivores like the cat had very little bitter receptor activity because it would be more important to herbivores and omnivores in order to keep them from eating poisonous plants.
However, “the numbers of functional bitter receptors in the terrestrial Carnivora we examined, including omnivorous and herbivorous species, were roughly comparable to that of cats thereby providing no strong support for the hypothesis that a strict meat diet influences bitter receptor number or function,” the PLOS One abstract reads. In other words, being an obligate carnivore makes no difference in the number of bitter taste receptors.
Taste receptors for sweet flavors developed in order for omnivorous species like humans to be able to sense plants and fruits that would provide a rich supply of carbohydrates and sugars, which our bodies metabolize in order to create energy. As obligate carnivores, cats have no need for, and can’t digest and process, carbohydrates, so evolution eventually deleted the gene for the sweet tooth.
Despite cats’ inability to process carbohydrates and sugars, most pet food manufacturers use grains as the primary ingredient in their products. “This may be why cats are getting diabetes,” said biochemist Joe Brand in a Scientific American article published shortly after cats’ lack of sweet taste receptors was discovered. “Cat food today has around 20 percent carbohydrates. The cats are not used to that, they can’t handle it.”
“Sure,” you might say, “so why does my cat always try to eat my ice cream?” Well, cats can detect the taste of fat, and there’s plenty of fat in ice cream!
At this point, it is known that cats can detect sour, salty, and meaty/savory (also known as “umami”) flavors. Given the role of the nose and the Jacobson’s organ in the perception of flavors, they may be able to taste flavors for which we don’t even have words.
As I said earlier, bitter receptors developed to protect mammals from consuming poisonous substances. Although we as omnivores think of those poisonous materials as plants, “The bitter taste could exist to minimize intake of toxic compounds from skin and other components of certain prey species, such as invertebrates, reptiles and amphibians,” says PLOS One study author Gary Beauchamp, Ph.D.
Think of all those nasty poisonous toads and insects found in tropical jungles — and the poisons that some cruel people put out to harm cats. But even beyond that, there are bitter substances in the bodies of cats’ typical prey. If you’ve ever seen a little blackish glob left untouched after your cat eats a mouse, that’s the gall bladder, which is filled with bitter bile.
Do you have any other questions or observations about your cat’s sense of taste? Please share them in the comments.
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About JaneA Kelley: Punk-rock cat mom, science nerd, animal rescue volunteer and all-around geek with a passion for bad puns, intelligent conversation, and role-play adventure games. She gratefully and gracefully accepts her status as chief cat slave for her family of feline authors, who have been writing their award-winning cat advice blog, Paws and Effect, since 2003.