YOUR PET IS NOT LIKE YOU

D ESPITE THE CRYPTIC name and anonymous office‑park architecture, the nature of the enterprise that goes on at AFB International is clear the moment you sit down for a meeting. The conference room smells like kibble. One wall of it, entirely glass, looks onto a small‑scale kibble extrusion plant where men and women in lab coats and blue sanitary shoe covers tootle here and there pushing metal carts. AFB makes flavor coatings for dry pet foods. To test the coatings, they first need to make small batches of plain kibble and add the coatings. The flavored kibbles are then presented to consumer panels for feedback. The panelists–Spanky, Thomas, Skipper, Porkchop, Rover, Elvis, Sandi, Bela, Yankee, Fergie, Murphy, Limburger, and some three hundred other dogs and cats–reside at AFB’s Palatability Assessment Resource Center (PARC), about an hour’s drive from the company’s suburban St. Louis headquarters.

AFB Vice President Pat Moeller, myself, and a few other staff members are seated around an oval conference table. Moeller is middle‑aged, likable, and plain‑spoken. He has a small mouth with naturally deep red lips and a pronounced Cupid’s bow, but it would be inaccurate to say he has a feminine appearance. Moeller once consulted for NASA, and he has that look. The fundamental challenge of the pet‑food professional, Moeller is saying, is to balance the wants and needs of pets with those of their owners. The two are often at odds.

Dry, cereal‑based pet foods caught on during World War II, when tin‑rationing put a stop to canning, including the canning of dog food made from horse meat (of which there was an abundance around the time Americans embraced the automobile and began selling their mounts to the knackers). Regardless of what pets made of the change, owners were delighted. Dry pet food was less messy and stinky, and more convenient. As a satisfied Spratt’s Patent Cat Food customer of yesteryear put it, the little biscuits were “both handy and cleanly.”

To meet pets’ nutrition requirements while also giving humans the cheap, handy, cleanly product they demand, mainstream pet‑food manufacturers blend animal fats and meals with soy and wheat grains and add vitamins and minerals. This yields a cheap, nutritious pellet that no one wants to eat. Cats and dogs are not grain‑eaters by choice, Moeller is saying. “So our task is to find ways to entice them to eat enough for it to be nutritionally sufficient.”

This is where “palatants” enter the scene. AFB designs powdered flavor coatings for the edible extruded shapes. Moeller came to AFB from Frito‑Lay, where his job was to design, well, powdered flavor coatings for edible extruded shapes. “There are,” he allows, “a lot of parallels.” A Cheeto without its powdered coating has almost no flavor.[10]Likewise, the sauces on processed convenience meals are basically palatants for humans. The cooking process for the chicken in a microwavable entrée imparts a mild to nonexistent flavor. The flavor comes almost entirely from the sauce–by design. Says Moeller, “You want a common base that you can put two or three or more different sauces on and have a full product line.”

Pet foods come in a variety of flavors because that’s what we humans like,[11]and we assume our pets like what we like. We have that wrong. “For cats especially,” Moeller says, “change is often more difficult than monotony.”

Nancy Rawson, seated across from me, is AFB’s director of basic research and an expert in animal taste and smell. She volunteers that cats are more or less “monoguesic,” meaning they stick to one food. Outdoor cats tend to be either mousers or birders, not both. But don’t worry, as 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.”

The extent to which Americans project their own food qualms and biases onto their pets has lately veered off into the absurd. Some of AFB’s clients have begun marketing 100 percent vegetarian kibble for cats. The cat is what’s called a true carnivore; its natural diet contains no plants.

Moeller tilts his head. A slight lift of the eyebrows. The look says, “Whatever the client wants.”

N ANCY RAWSON KNOWS how to get a cat to finish its vegetables. Pyrophosphates have been described to me as “cat crack.” Coat some kibble with it, and you, the pet‑food manufacturer, can make up for a whole host of gustatory shortcomings. Rawson has three kinds of pyrophosphate in her office. They’re in plain brown‑glass bottles, vaguely sinister in their anonymity. I asked to try them, 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, though I also accept the possibility that other people would find the two of us odd.

Rawson is dressed today in a floral‑print skirt, on the long side, 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. She is brainy and hard working, committed to her job in a way you don’t necessarily expect pet‑food people to be. Before she was hired at AFB, she was a nutritionist at Campbell’s Soup Company, and before that, she did research on animal taste and smell at the Monell Chemical Senses Center.

Rawson unscrews the cap of one of the bottles. She pours a finger of clear liquid into a plastic cup. Though 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 into 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, ‘Oooo, 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,[12]simply because it has so many receptors. They are all over its skin. “Catfish are 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.

I try to imagine what life would be like if humans tasted things by rubbing them on their skin. Hey, try this salted caramel gelato, it’s amazing. Rawson points out that a catfish may not consciously perceive anything when it tastes its food. The catfish neurological system may simply direct the muscles to eat. It seems odd to think of tasting without any perceptive experience, but you may be doing it right now. Humans have taste receptor cells in the gut, the voice box, the upper esophagus, but only the tongue’s receptors report to the brain. “Which is something to be thankful for,” says Danielle Reed, Rawson’s former colleague at Monell. Otherwise you’d be tasting things like bile and pancreatic enzymes. (Intestinal taste receptors are thought to trigger hormonal responses to molecules, such as salt and sugar, and defensive reactions–vomiting, diarrhea–to dangerous bitter items.)

We consider tasting to be a hedonic pursuit, but in much of the animal kingdom, as well as in our own prehistory, the role of taste was more functional than sensual. Taste, like smell, is a doorman for the digestive tract, a chemical scan for possibly dangerous (bitter, sour) elements and desirable (salty, sweet) nutrients. Not long ago, a whale biologist named Phillip Clapham sent me a photograph that illustrates the consequences of life without a doorman. Like most creatures that swallow their food whole, sperm whales have a limited‑to‑nonexistent sense of taste. The photo is a black‑and‑white still life of twenty‑five objects recovered from sperm whale stomachs. It’s like Jonah set up housekeeping: a pitcher, a cup, a tube of toothpaste, a strainer, a wastebasket, a shoe, a decorative figurine.

Enough stalling. Time to try the palatant. I raise the cup to my nose. It has no smell. I roll some over my tongue. All five kinds of taste receptors stand idle. It tastes like water spiked with strange. Not bad, just other. Not food.

“It may be that that otherness is something specific to the cat,” says Rawson. Perhaps some element of the taste of meat that humans cannot perceive. The feline passion for pyrophosphates might explain the animal’s reputation as a picky eater. “We make [pet food] choices based on what we like,” says Reed, “and then when they don’t like it, we call them finicky.”

There is no way to know or imagine what the taste of pyrophosphate is like for cats. It’s like a cat trying to imagine the taste of sugar. Cats, unlike dogs and other omnivores, can’t taste sweetness. There’s no need, since the cat’s diet in the wild contains almost nothing in the way of carbohydrates (which include simple sugars). Either cats never had the gene for detecting sweet, or they lost it somewhere down the evolutionary road.

Rodents, on the other hand, are slaves to sweetness. They have been known to die of malnutrition rather than step away from a sugar‑water drip. In an obesity study from the 1970s, rats fed an all‑you‑can‑eat “supermarket” diet that included marshmallows, milk chocolate, and chocolate‑chip cookies gained 269 percent more weight than rats fed standard laboratory fare. There are strains of mice that will, over the course of a day, consume their own bodyweight in diet soda, and you do not want the job of changing their bedding.

Does that mean rodents feel pleasure in tasting sweet things the same way we do? Or is it simply a sequence of programmed responses, receptors sending signals and signals driving muscles? Video footage Danielle Reed sent me suggests that rodents do consciously perceive and savor the taste of something sweet. One clip shows a white mouse that has just been drinking sugar solution. She is shown in ultra‑slow motion, filmed from below through a clear plastic floor, licking the fur around the sides of her mouth. (The caption uses the scientific term for lip‑licking: “lateral tongue protrusion.”) Another clip shows a mouse that has just tasted denatonium benzoate, a bitter compound that parents used to paint on their children’s fingertips to discourage nail‑biting. The mouse is doing everything it can to rid itself of traces of the chemical. It shakes its head and rubs its face with its hairy white forelegs. It pulls a “gape”: mouth opened wide, tongue stuck out to eject the offending food. (Humans do this too. The scientific term here is “the disgust face.”)

“If it’s exceedingly nasty,” Reed told me, “they will actually drag their tongue on the bedding to try to get it off.” Clearly taste matters to them.

Conversely, do animals with no taste buds derive no pleasure from eating? Is it just a daily chore? Has anyone observed–in, say, a python eating a rat–those same parts of the brain that light up when humans are experiencing taste delight? Reed doesn’t know. “But no doubt somewhere in the world there’s a scientist trying to get a live python into an fMRI machine.”

Rawson points out that although snakes can’t taste, they have a primitive sense of smell. They’ll extend their tongue to gather volatile molecules and then pull it back in and plug it into the vomeronasal organ at the roof of the mouth to get a reading. Snakes are keenly attuned to the aroma of favored prey–so much so that if you slip a rat’s face and hide, Hannibal Lecter–style, over the snout of a non‑favored prey item, a python will try to swallow it. (University of Alabama snake digestion expert Stephen Secor did this some years back to reenact a scene for National Geographic television. “Worked like a charm,” he told me. “I can get a python to eat a beer bottle if I put a rat head on it.”)

For part of their development, human fetuses have a vomeronasal organ, though no one knows whether it’s functional. You can no more ask a fetus about these things than a python. Rawson surmises that the organ is a holdover from “when we were crawling out of the primordial soup,[13]and we needed to sense the chemicals in the environment and know which ones to go toward or away from.”

Rawson has an idea of what it is like to eat without perceiving tastes, because she has talked to cancer patients whose taste receptors have been destroyed by radiation treatments. The situation is well beyond unpleasant. “Your body is saying, ‘It’s not food, it’s cardboard,’ and it won’t let you swallow. No matter how much you tell your brain that you need to eat to survive, you’ll gag. These people can actually die of starvation.” Rawson knows a researcher who has been experimenting with using potent flavors–which, as we know from the last chapter, are mainly smells–to make up for absent tastes. Taste and smell are intertwined in ways we don’t consciously appreciate. Food technologists sometimes exploit the synergy between the two. By adding strawberry or vanilla–aromas we associate with sweetness–it’s possible to fool people into thinking a food is sweeter than it really is. Though sneaky, this is not necessarily bad, because it means the product can contain less added sugar.

Which takes us back to palatants, and why pet‑food manufacturers love them. As one AFB employee put it, “The client can go, ‘Here’s my product. I want to cut corners here and here and here, and I want you to cover up all the sins.’” This is especially doable with dog food, as dogs rely more on smell than taste in making choices about what to eat and how vigorously. (Pat Moeller estimates that for dogs, the ratio for how much aroma matters to how much taste matters is 70/30. For cats, the ratio is more like 50/50.) The takeaway lesson is that if the palatant smells appealing, the dog will dive in with instant and obvious zeal, and the owner will assume the food is a hit. In reality it may have only smelled like a hit.

Interpreting animals’ eating behaviors is tricky. By way of example, one of the highest compliments a dog can pay its food is to vomit. When a “gulper,” to use Pat Moeller’s terminology, is excited by the aroma of a food, it will wolf down too much too fast. The stomach overfills, and the meal is reflexively sent back up to avoid any chance of a rupture. “No consumer likes that, but it’s the best indication that the dog just loved it.” Fortunately for the staff at the AFB Palatability Assessment Resource Center, there are other ways to gauge a pet food’s popularity.

“E VERYONE WANTS TO be Meow Mix.” Amy McCarthy, head of PARC, stands outside the plate‑glass window of Tabby Room 2, where an unnamed client is facing off against Meow Mix, Friskies, and uncoated kibble in a preference test. If a client wants to be able to say that cats prefer its product over Meow Mix, they must prove it at a facility like PARC.

Two animal techs dressed in tan surgical scrubs stand facing each other. They hold shallow metal pans of kibble in various shades of brown,[14]one in each hand. Around their ankles, twenty cats mince and turn. The techs sink in tandem to one knee, lowering the pans.

The difference between dog and cat is immediately obvious. While a dog almost (and occasionally literally) inhales its food the moment it’s set down, cats are more cautious. A cat wants to taste a little first. McCarthy directs my gaze to the kibble that has no palatant coating. “See how they feel it in their mouth and then drop it?”

I see an undifferentiated ground‑cover of bobbing cat heads, but nod anyway.

“Now look there.” She directs my gaze to the Meow Mix, where the bottom of the pan is visible through an opening in the kibble. I ask McCarthy if there’s an industry term[15]for the open spot.

“Um … ‘The space where kibble used to be’?” McCarthy speaks louder than you expect a person to, perhaps a side effect of time spent talking over barking. She is in her thirties, with blonde hair that is center‑parted and wants to fall in her face. Every few minutes, she’ll raise both forefingers to the sides of her face to nudge it back. Rawson’s hair, by contrast, is cropped close to her head. It’s a “pixie cut,” but those probably aren’t the words she used when she discussed it with her haircutter. Rawson has come with me to PARC because she hasn’t yet visited and wants to learn how the preference testing is being done and how the techniques might be improved.

Meanwhile, down the hallway, dog kibble A, dressed in a coat of newly formulated AFB palatant, is up against the competitor. The excitement is audible. One dog squeals like sneaker soles on a basketball court. Another makes a huffing sound reminiscent of a two‑man timber saw. The techs are wearing heavy‑duty ear protection, the kind worn on airport tarmacs.

A tech named Theresa Kleinsorge opens the door of a large kennel crate and sets down two bowls in front of a terrier mix with dark‑ringed eyes. Theresa is short and brassy, with spiky magenta‑dyed hair. Kleinsorge is German for “little trouble,” and it seems like a good name–trouble in the affectionate sense of well‑intentioned mischief. She owns seven dogs. Amy McCarthy shares her home with six. Dog love is palpable here at PARC. It is the first pet‑food test facility to “group‑house” its animals. Other than during certain preference tests, when animals are crated to avoid distractions, PARC is a cageless facility. Groups of dogs, matched by energy level, spend their days roughhousing in outdoor yards.

The terrier mix is named Alabama. His tail thumps a beat on the side of the crate. “Alabama is a gobbler real bad,” Theresa says. In making their reports, the AFB techs must take into account the animals’ individual mealtime quirks. There are gulpers, circlers, tippers, snooters. If you weren’t acquainted with Alabama’s neighbor Elvis, for example, you’d think he was blasé about both foods just now set before him. Theresa gives a running commentary of Elvis’s behavior while a colleague jots notes. “Sniffing A. Sniffing B. Licking B, licking his paws. Going back to A. Looking at A. Sniffing B. Eating B.”

Most dogs are more decisive. Like Porkchop. “You’ll see. He’ll sniff both, pick one, eat it. Ready?” She puts two bowls by Porkchop’s front paws. “Sniffing A, sniffing B, eating A. See? That’s what he does.”

PARC techs also try to keep a bead on doggy interactions in the yards. “We need to know,” says McCarthy. “‘Are you down because you don’t like the food or because Pipes stole your bone earlier?’” Theresa volunteers that a dog named Rover has lately had a stomach upset, and Porkchop likes to eat the vomit. “So that’s cutting into Porkchop’s appetite.” And probably yours.

In addition to calculating how much of each food the dogs ate, PARC techs tally the first‑choice percentage: the percentage of dogs who stuck their snout in the new food first. This is important to a pet‑food company because with dogs, as Moeller said earlier, “if you can draw them to the bowl, they’ll eat, most of the time.” Once the eating begins, though, the dog may move to the other food and wind up consuming more of it. Since most people don’t present their dog with two choices, they don’t know the extent to which their pet’s initial, slavering, scent‑driven enthusiasm may have dimmed as the meal went on.

The challenge is to find an aroma that drives dogs wild without making their owners, to use an Amy McCarthy verb, yack. “Cadaverine is a really exciting thing for dogs,” says Rawson. “Or putrescine.” But not for humans. These are odoriferous compounds given off by decomposing protein. I was surprised to learn that dogs lose interest when meat decays past a certain point. It is a myth that dogs will eat anything. “People think, Dogs love things that are old, nasty, drug around in the dirt,” Moeller told me earlier. But only to a point, he says. And for a reason. “Something that’s just starting to decay still has full nutritional value. Whereas something where the bacteria have really broken it down, it’s lost a lot of its nutritional value and they would only eat it if they had no choice.” Either way, a pet owner doesn’t want to smell it.

Some dog‑food designers go too far in the other direction, tailoring the smell to be pleasing to humans[16]without taking the dog’s experience of it into account. The problem is that the average dog’s nose is about a thousand times more sensitive than the average human’s. A flavor that to you or me is reminiscent of grilling steak may be overpowering and unappealing to a dog.

Earlier in the day, I watched a test of a mint‑flavored treat marketed as a tooth‑cleaning aid. Chemically speaking, mint, like jalapeño, is less a flavor than an irritant. It’s an uncommon choice for a dog treat.[17]The manufacturers are clearly courting the owners, counting on the association of mint with good oral hygiene. The competition courts the same dental hygiene association but visually: the biscuit is shaped like a toothbrush. Only Rover preferred the minty treats. Which maybe explains the vomiting.

A dog named Winston is nosing through his bowl for the occasional white chunk among the brown. Many of the dogs picked these out first. They’re like the M&M’s in trail mix. McCarthy is impressed. “That’s a really, really palatable piece in there.” One of the techs mentions that she tried some earlier, and that the white morsels are chicken. Or rather, “chickeny.”

I must have registered surprise at the disclosure, because Theresa jumps in. “If you open up a bag and it smells really good–”

The tech shrugs. “And you’re hungry…”

I N 1973 THE nutritional watchdog group Center for Science in the Public Interest (CSPI) published a booklet titled Food Scorecard , which made the claim that one‑third of the canned dog food purchased in housing projects was consumed by people. Not because they’d developed a taste for it, but because they couldn’t afford a more expensive meat product. (When a reporter asked where the figure had come from, CSPI founder Michael Jacobson couldn’t recall, and to this day the organization has no idea.)

To my mind, the shocker was in the scores themselves. Thirty‑six common American protein products were ranked by overall nutritional value. Points were awarded for vitamins, calcium, and trace minerals, and subtracted for added corn syrup and saturated fats. Jacobson–believing that poor people were eating significant amounts of pet food, and/or exercising his talent for publicity–included Alpo in the rankings. It scored 30 points, besting salami and pork sausage, fried chicken, shrimp, ham, sirloin steak, McDonald’s hamburgers, peanut butter, pure‑beef hotdogs, Spam, bacon, and bologna.

I mention the CSPI rankings to Nancy Rawson. We are back at AFB headquarters, with Moeller again, in a different conference room. (There are five: Dalmatian, Burmese, Greyhound, Calico, and Akita. The staff refer to them by breed, as in, “Do you want to go into Greyhound?” “Is Dalmatian free at noon?”) It would seem that in terms of nutrition, there was no difference between the cheap meatball sub I ate for lunch and the SmartBlend the dogs were enjoying earlier. Rawson disagrees. “Your sandwich was probably less complete, nutritionally.”

The top slot on the CSPI scorecard, with 172 points, is beef liver. Chicken liver and liver sausage took second and third place. A serving of liver provides half the RDA for vitamin C, three times the RDA for riboflavin, nine times the vitamin A in the average carrot, plus good amounts of vitamins B12, B6, and D, folic acid, and potassium.

What’s the main ingredient in AFB’s dog‑food palatants?

“Liver,” says Moeller. “Mixed with some other viscera. The first part that a wild animal usually eats in its kill is the liver and stomach, the GI tract.” Organs in general are among the most nutritionally giving foods on Earth. A serving of lamb spleen has almost as much vitamin C as a tangerine. Beef lung has 50 percent more. Stomachs are especially valuable because of what’s inside them. The predator benefits from the nutrients of the plants and grains in the guts of its prey. “Animals have evolved to survive,” Rawson says. They like what’s best for them. People blanch to see “fish meal” or “meat meal” on a pet‑food ingredient panel, but meal–which variously includes organs, heads, skin, and bones–most closely resembles the diet of dogs and cats in the wild. Muscle meat is a grand source of protein, but comparatively little else.

Animals’ taste systems are specialized for the niche they occupy in the environment. “That’s driven their sensory systems down a certain path,” Rawson says. This includes the animal known as us. As hunters and foragers of the dry savannah, our earliest forebears evolved a taste for important but scarce nutrients: salt and high‑energy fats and sugars. On the African veldt, unlike at the American food court, fats, sugar, and salt were not easy to come by. That, in a nutshell, explains the widespread popularity of junk food. And wide spreads in general.

Like dogs, humans also need a broad range of vitamins, minerals, calcium. We’re omnivores. Early man didn’t throw away the most nutritious parts of a carcass. Why ever do we? In 2009, the United States exported 438,000 tons of frozen livestock organs. You could lay them end to end and make a viscera equator. Figuratively speaking, they already ring the globe. Egypt and Russia are big on livers. Mexico eats our brains and lips. Our hearts belong to the Philippines.

What happened here? Why are we so squeamish? How hard would it be to go back to our healthier origins? For answers, we head to the Canadian Arctic, last stronghold of the North American organ‑meat dinner.

3. Liver and Opinions