A couple of years ago, Anne Carlson — the founder of Jiminy’s, a dog food start-up — conducted a taste test with her dog, Timber.

She filled half of his bowl with the meat-based food the Great Dane was used to eating, and she filled the other half with Jiminy’s Cricket Crave, a kibble made from cricket powder, oats, quinoa, sweet potato and other plant-based ingredients. Then she stood back as he dug in.

Timber’s response was miraculous: He sniffed his options, then devoured the Cricket Crave and licked his lips contentedly, leaving the other side untouched.

“It was one of those moments when you’re like, ‘Oh, this is so good,’ ” Carlson said. This summer, Petco stocked shelves in 800 stores with Jiminy’s dog food. Along with the surprise of seeing pets wolf down insects, Carlson says customers often tell her, “I didn’t even realize I could be fighting climate change with my dog.”

Many pet owners reflexively bark “No!” when their dog or cat prepares to feast on a bug. But despite what scientists call the “yuck factor,” insects could be a sustainable secret ingredient for the booming pet food industry. About a quarter of Americans are cutting back on eating meat, many alarmed by the fact that livestock farming causes up to 15 percent of global greenhouse gas emissions. Yet for all the humans observing meatless Mondays, opting for Impossible burgers or swearing off meat entirely, 180 million furry members of U.S. households are fed beef, lamb, poultry or pork in just about every meal.

Researchers at the University of California at Los Angeles estimate that dogs and cats account for up to 30 percent of the environmental impact of U.S. meat consumption. If American pets made up their own country, they’d eat the fifth-most meat globally. And fueled by a surge of pandemic pet acquisitions, Americans now spend more than $40 billion annually on pet food and treats — with many stores offering almost exclusively traditional meat-based options.

But there are signs of a shift. Many pet food companies — including the two biggest, Mars and Nestlé — are developing insect-based alternatives for dogs and cats, and according to a Petco survey, 55 percent of customers like the idea of using sustainable alternative protein ingredients in pet food.

Millennials, the fastest-growing contingent of pet owners, are keen on buying environmentally friendly products and willing to pay a premium for them, according to Francesca Mahoney, Petco’s head of sustainability.

“There’s an appetite for pet parents to spend a little bit more if something resonates with their values,” Mahoney said. Petco wants half of its products to be sustainable by 2025.

For now, some pet owners might balk at the higher price of these alternatives. Petco sells a 3.5-pound bag of Jiminy’s Cricket Crave for $21.95 — almost three times more than Purina’s chicken and rice dry food. But the cost of insects, driven up temporarily by nutritional testing and a supply chain with enormous room to scale, is expected to drop as the market grows.

Carlson founded Jiminy’s in 2016, after reading a United Nations report identifying crickets as a sustainable source of food for humans. After all, insects are already a culinary staple in much of the world: grasshoppers fried in Thailand, worms floating in mezcal in Mexico, caterpillars boiled in the Congo. The edible insect market is projected to grow eightfold globally by 2030, to $8 billion.

Carlson herself drinks smoothies with a dash of cricket powder. Her company sells Cricket Crave as well as Good Grub, which derives protein from black soldier fly larvae. As a pet food, “there are no compromises,” she said. “It’s humane. It’s hypoallergenic. It’s delicious.”

And, Carlson added, insects produce something many pet owners obsessively monitor: “solid poops.” Crickets and fly larvae are similarly digestible to traditional meat and provide comparable protein, plus vital amino acids and other minerals, according to Kelly Swanson, an animal nutritional scientist at the University of Illinois.

Although many pets eat the same menu of wet and dry food every day of their lives, Swanson says a rotational diet is often the most nutritious. When cutting back on meat, “it’s not all or nothing,” he says, adding that for his own diet, “I’ll take out one or two meat meals per week. With pets, 10 percent of protein coming from insects adds up sustainability-wise.”

An acre of land can produce about 192 pounds of beef annually, or 265 pounds of poultry, according to Carlson. The same space yields 65,000 pounds of cricket or 130,000 pounds of black soldier fly larvae. Farming insects releases substantially less carbon and methane, and, according to Jiminy’s “carbon pawprint” calculator, switching a Golden Retriever to an insect-based diet saves 4.4 million gallons of water per year.

Much of Jiminy’s crickets come from Entomo Farms in Ontario, Canada. The company, which expects sales to increase fourfold this year, retrofitted rural chicken farms to house millions of crickets in climate-controlled “cabins.” One might think a barn full of crickets would be as deafening as a Toronto Raptors playoff game, but no: Crickets only chirp in old age, and Entomo’s crickets live 80 percent of their natural life span before being processed.

In August, the Association of American Feed Control Officials, an influential body for establishing pet nutritional standards, voted to approve black soldier fly larvae for dog food. (AAFCO has yet to issue a verdict on crickets.) Jiminy’s gets its dried fly larvae from Kentucky-based EnviroFlight, which opened the first commercial-scale U.S. fly farm in 2019. At any given time there are billions of creatures under one roof — about 5 percent flies and 95 percent larvae, living vertically up to 15 feet.

Flies are raised in a “circular economy,” said EnviroFlight President Liz Koutsos, an animal nutritionist. They are fed with byproducts from local bourbon distilleries and bakeries, and the waste from larvae then goes toward animal feed. “Nothing ends up in the landfill,” Koutsos said.

Many meat-based pet foods use animal byproducts humans won’t eat — mostly bones and organs like the spleen, kidney and heart — supposedly reducing their footprint. Caitlyn Dudas, executive director of the Pet Sustainability Coalition, says the pet food industry would be better off dialing back its dependence on factory livestock farming. “We are not clear of responsibility for the farming practices for our products” from animals, she said, whereas “insect protein is legitimately sustainable.”

For now, Europeans have a greater appetite to serve insects to their pets. Nestlé’s Purina line of insect-based dry dog food is sold in about 200 stores in Switzerland, and the company expects distribution to double by October. This spring, Mars — having found that 47 percent of Europeans would buy insect-based cat food — launched a black soldier fly larvae-based cat kibble, Lovebug, in the United Kingdom.

“With protein sourcing, there is a symbiotic relationship between the human food supply chain and the pet supply chain,” said Deri Watkins, president of Mars Petcare’s European division. “I'd be surprised if five years from now, you're not seeing the option of insect protein on a mainstream supermarket shelf.”

Companies are still refining how to market insects, too. When Jonathan Persofsky performed focus-group testing for his Green Gruff cricket-based dog treats, packages covered with images of bugs scored very poorly. When he explained the nutritional and environmental upside of crickets, however, 88 percent of people said they’d buy his product.

Maryanne Murphy, a veterinary nutritionist at the University of Tennessee, isn’t surprised that people are turned off by the sight of bugs. The pet food industry already panders to human palettes, marketing such novelties as Memphis-style BBQ chicken for dogs and seafood paella for cats. “When I talk to [pet] owners about it, they say, ‘Would I want to eat insects?’ ” Murphy said.

Although humans can easily cut back on mainstream meat options, many people question whether that’s true of their pets. Cats are called “obligate carnivores,” meaning they depend on the micronutrients found in meat. But “insect protein fulfills that need,” Watkins said, and at a minimum, cats and dogs appear to benefit from insects as a complementary protein source.

D.C.-based Chippin also makes treats from cricket powder, plus dog foods made with spirulina or invasive carp. “It’s shocking,” CEO Haley Russell said, “that you see people walking through Whole Foods, putting plant-based foods in their reusable bags, but when you hit the pet food aisle so much of it is conventional meat protein.”

About a year ago, Jonathan Carrion, owner of Brooklyn Tails Pet Food, began selling cricket treats. He liked that they’re high in protein, and remembered watching his cat enjoy eating insects she found outside.

But after displaying them in the front of his store, Carrion decided not to restock. “About 50 percent of customers thought crickets were disgusting,” he said, “like I told them it was made out of cockroaches.”

Ultimately, there’s still a major learning curve to overcome in the United States, even in the most environmentally conscientious neighborhoods. He thinks insect-based pet food companies should offer free samples or provide brochures, like CBD-based pet products do, to explain the many benefits of feeding insects to pets.

“People who took samples would come right back, asking, ‘Hey, do you have any more cricket stuff?’ ” Carrion said. “Animals love it.”