
Nancy Rawson, seated across from me, is AFB’s director of basic research and an expert in animal taste and smell. She says that cats prefer to stick to one type of food. Outdoor cats tend to be either mousers or birders, but not both. But don’t worry: Most of the difference between Tuna Treat and Poultry Platter is in the name and the picture on the label. “They may have more fish meal in one and more poultry meal in another,” says Moeller, “but the flavors may or may not change.”
To gauge the acceptability of a new product, food science has traditionally relied on consumer panels: willing individuals who sample an array of products and report back on which they prefer. It’s no different with pets. It’s just that you can’t ask them.
Pyrophosphates have been described to me as “cat crack.” Coat some kibble with it, and the pet food manufacturer can make up for a whole host of gustatory shortcomings. Rawson has three kinds of pyrophosphates in her office. They’re in plain, brown glass bottles, vaguely sinister in their anonymity. I have asked to try some, which, I think, has won me some points. Sodium acid pyrophosphate, known affectionately as SAPP, is part of the founding patent for AFB, yet almost no one who works for the company has ever asked to taste it. Rawson finds this odd. I do, too, although I also accept the possibility that other people would find the two of us odd.
Rawson is dressed today in a long, floral-print skirt with low-heeled brown boots and a lightweight plum-colored sweater. She is tall and thin with wide, graceful cheek and jaw bones. She looks at once like someone who could have worked as a runway model and someone who would be mildly put off to hear that. Before she was hired at AFB, Rawson worked as a nutritionist at Campbell Soup Company and, before that, did research on animal taste and smell at the Monell Chemical Senses Center in Philadelphia.
Rawson unscrews the cap of one of the bottles. She pours a finger of clear liquid into a plastic cup. Although pet food palatants most often take the form of a powder, liquid is better for tasting. To experience taste, the molecules of the tastant—the thing one is tasting—need to dissolve in liquid. Liquid flows into the microscopic canyons of the tongue’s papillae, coming into contact with the buds of taste receptor cells that cover them. That’s one reason to be grateful for saliva. Additionally, it explains the appeal of dunking one’s doughnuts.
Taste is a sort of chemical touch. Taste cells are specialized skin cells. If you have hands for picking up foods and putting them in your mouth, it makes sense for taste cells to be on your tongue. But if, like flies, you don’t, it may be more expedient to have them on your feet. “They land on something and go, ‘Ooh, sugar!’ ’’ Rawson does her best impersonation of a housefly. “And the proboscis automatically comes out to suck the fluids.” Rawson has a colleague who studies crayfish and lobsters, which taste with their antennae. “I was always jealous of people who study lobsters. They examine the antennae, and then they have a lobster dinner.”
The study animal of choice for taste researchers is the catfish, simply because it has so many receptors. They are all over its skin. “They’re basically swimming tongues,” says Rawson. It is a useful adaptation for a limbless creature that locates food by brushing up against it; many catfish species feed by scavenging debris on the bottom of rivers.
single page140 years of Popular Science at your fingertips.
Each issue has been completely reimagined for your iPad. See our amazing new vision for magazines that goes far beyond the printed page
Stay up to date on the latest news of the future of science and technology from your iPhone or Android phone with full articles, images and offline viewing
Featuring every article from the magazine and website, plus links from around the Web. Also see our PopSci DIY feed
For our annual How It Works issue, we break down everything from the massive Falcon Heavy rocket to a tiny DNA sequencer that connects to a USB port. We also take a look at an ambitious plan for faster-than-light travel and dive into the billion-dollar science of dog food.
Plus the latest Legos, Cadillac's plug-in hybrid, a tractor built for the apocalypse, and more.


Online Content Director: Suzanne LaBarre | Email
Senior Editor: Paul Adams | Email
Associate Editor: Dan Nosowitz | Email
Assistant Editor: Colin Lecher | Email
Assistant Editor:Rose Pastore | Email
Contributing Writers:
Rebecca Boyle | Email
Kelsey D. Atherton | Email
Francie Diep | Email
Shaunacy Ferro | Email
Kibble: Never A Good Option
www.dogsnaturallymagazine.com/kibble-never-a-good-option/
Sigh, this article is harolding "better" kibble based off more meat products. Auroria's article is based off cheaper cardboard-ish kibble. Both are biased. If your dog is happy and healthy, who cares?
Must be doing something wrong, I've fed all of my dogs kibble, and not the expensive, organic, scientific stuff either. They have lived long, healthy lives. Healthy enough that when I have to change vets, they always comment on my pets' condition and say, "You must be feeding them the expensive, organic, scientific stuff!" "No, no, and nope."
Thanks for the fascinating article. I laughed out loud a couple of times.
While “The Chemistry of Kibble” [April, 2013] provided an interesting insight into what most pet food manufacturers try to do to make their food palatable. The article states that pet foods are mixed with “soy and wheat grains… [and that] cats and dogs are not grain eaters.” I think it is worth noting that there are plenty of pet foods available that are grain-free that do not require tricks to “entice [pets] to eat enough for it to be nutritionally sufficient.”
One wonders where Spanky, Thomas, Skipper, Porkchop, Mohammid, Elvis, Sandi, Bela, Yankee, Fergie, Murphy, Limburger, and some 300 other dogs and cats came from before they 'resided' in a lab cage at this facility and where they'll go once the lab is finished with them. There are plenty of good kibble manufacturers who make high quality food without using lab animals to taste-test. Given the ultimate consumers are pets at home, it makes more sense to taste test to pooches with the diet and lifestyle of a pet, rather than lab animal.
This is an unnecessary article glorifying an extremely unnecessary 'science' industry created not for pet health or welfare, but simply profit.
Absolute garbage. Why must everything have some freekin' chemical to cover up the fact that it's made with more chemicals and processed crap? I like Doritos, but I'm not going to live on them no matter how tasty they are.
First off, the first ingredient of these cheap kibble recipes is corn meal, wheat is way down the list, and K9's cannot digest cornmeal. It requires feeding them twice as much kibble to get the benificial protein that they need at the risk of overloading them on the carbohydrates that they do not need, which not only is bad for them and causes weight gain, but also much higher rates of digestive and health issues along with shortend life spans and quality of life in their later years. Cheap kibble is also way more expensive in reality because you do feed twice as much as you would with premium foods that are not quite double the price. If you feed a 90lb. dog 3 cups of cheap kibble twice a day along with canned food, you could do the same job with just 2 cups of premium kibble twice a day with no canned food at all. Premium kibble is almost all protein, this is the fuel K9's require for a long vibrant life. Not to mention that they leave alot less waste to clean up and are way less gassy.
All of our rescues have come in overweight and lethargic compared to their healthy counterparts, even at 4 and 5 years old they acted closer to 10 in vitality, 2 months of premium and not only do they lose weight dramatically, they regain their vibrance and playfullness, coats improve and problem health issues diminish add to the overall reduction in the cost of caring for your best friend.
Sure, you can go cheap, but your buddy will die sooner and the last years of his life will suck compared to a life of proper nutrition. Not one K9 trainer will ever recommend a cheap kibble brand, even iams has corn meal in it. TIP: if you see a comercial for it, it's garbage, if it's sold in a grocery store, it's garbage. Pet store and feed houses are where you find what you need, they rarely carry grain based food. If you see corn anywhere in the ingredient list, move on. Try it for a couple of months, you will see the difference and you will spend less over time. The only downside is that your dog will be more energetic.
I can change my cats' food any time I want, as long as the new stuff costs more than the old stuff. The problem is, I can never reverse the process.
I thoroughly enjoyed this article and its insights. I turned away from kibble long ago and I'm glad that I did.