Read Gulp: Adventures on the Alimentary Canal for Free Online

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, * 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 * 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