Carol Will, owner of Lola & Penelope's Pet Boutique, right, talks about pet foods with cat owner Sarah Mangrum on Friday in St. Louis. Will's organic food sales have increased after a wide-spread pet food recall.

St. Louis ? When dog lover Carol Will heard that tainted wheat gluten had spurred a pet food recall, she wasn’t surprised to find out the commodity ingredient was used in a lot of generic brands like Hy-Vee and Price Chopper.

But Nutro Natural Choice? That’s top-shelf stuff.

“That made me sit up and say: ‘Wait a second, I need to look into this further,'” Will recalled.

Will has more than her own pets to worry about. She makes a living selling high-end dog food – along with doggy dresses and raincoats – at her store, Lola & Penelope’s Premier Pet Boutique and Wellness Center.

Will stakes her business on assuring customers the food they buy is healthy. That’s why they spend $58 for a 20-pound bag of dog food made with free-range chicken.

That Will was worried she might be hit by the recall highlights a question that pet owners around the country are facing: Are luxury pet food brands that different from the cheaper stuff?

“The foods are basically the same up to a point,” said David Kirkpatrick, spokesman for the American Veterinary Medical Association.

Pet food companies distinguish the more expensive brands by blending in higher-quality ingredients like canola oil, lamb meat or vitamin supplements. But a few building-block ingredients are common to almost any pet food brand on sale in a typical grocery store aisle, Kirkpatrick said.

Commodity products like corn gluten, wheat gluten and meat meal form the nutritional backbone of many pet foods, said Robert Backus, assistant professor of small animal nutrition at the University of Missouri.

“You’ll find those in many of the dry types of pet food and canned foods,” Backus said.

That’s why 95 brands of pet food were caught up in the recent recall, when just one manufacturer was found to have tainted ingredients. The New York State Department of Agriculture and Markets said Friday that rat poison was found in products made by Menu Foods Inc.

Inspectors thought wheat gluten found in the products was linked to the deaths of at least 16 cats and dogs nationwide. The tainted ingredient led to the recall of 60 million cans and pouches of Menu Foods pet foods nationwide.

Backus said consumers can check the ingredient labels on their pet food to see what it’s made of. But even that can be tricky. Cheaper brands might be made of “meat meal” while higher-end brands have ingredients listed simply as beef or chicken.