Josh Hafner

USA TODAY

A DNA testing of chicken sold at Subway restaurants in Canada revealed that two of the chain's popular sandwiches contain poultry that's only part meat, according a Canadian Broadcasting Corporation report.

A DNA researcher from Ontario's Trent University analyzed six grilled chicken sandwiches from fast food chains for the CBC's Marketplace program and found that while most sandwiches—from chains including McDonald's, Wendy's and A&W—contained "very close" to 100% chicken, the Subway products fell woefully short.

The chain's oven roasted chicken tested as 53.6% chicken DNA, CBC reported, while strips of its sweet onion chicken teriyaki registered as 42.8% chicken DNA.

While straight-from-the-store chicken should test at 100%, adding seasoning or marinating chicken would necessarily bring that number down. (Wendy's grilled chicken sandwich, for example, tested at 88.5% chicken DNA.)

Subway's chicken tested so low that researchers at Trent University's Wildlife Forensic DNA Laboratory analyzed an additional five samples of each product, which confirmed the original results.

Most of the chicken's non-meat DNA was soy, the broadcaster said.

Subway, the world's most ubiquitous fast food chain, disputed the findings in a statement to the CBC, claiming its "chicken strips and oven roasted chicken contain 1% or less of soy protein."

On Thursday, the company issued a statement saying that it had commissioned its own lab tests in response to the CBC's "false and misleading" report that showed its chicken contained only trace amounts of soy.

The company said it sent samples of its Canadian products to two labs, Maxxam Analytics in Ontario and Elisa Technologies in Florida. The results from both found less than 1% of the products contained soy protein, it said.

In an initial statement earlier this week, Subway Canada's said it was "concerned by the alleged findings you cite with respect to the proportion of soy content," and that it would "look into this again with our supplier to ensure that the chicken is meeting the high standard we set for all of our menu items and ingredients."

Later, however, Subway spokesman Kevin Kane came out swinging at the CBC's report. In a statement published Wednesday in Consumer Affairs, Kane said called the analysis "absolutely false and misleading.”

“Our chicken is 100% white meat with seasonings, marinated and delivered to our stores as a finished, cooked product," Kane wrote. "We have advised them of our strong objections. We do not know how they produced such unreliable and factually incorrect data, but we are insisting on a full retraction. Producing high quality food for our customers is our highest priority. This report is wrong and it must be corrected.”

CBC had issued no clarification or correction for its report as of Wednesday afternoon. As the Washington Post noted, the CBC's analysis was not subject to peer review or submitted to any scientific journal. But CBC's findings would be far from the first to tarnish the public's trust in Subway's ingredients.

The company faced backlash in 2014 after a health blogger criticized its bread for containing azodicarbonamide, an ingredient found in yoga mats as well as food served at McDonald's and Starbucks. Subway later phased it out of its products.

In 2015, Subway said it would start measuring its footlong subs in response to a lawsuit claiming customers were shorted centimeters of food.

Subway built its brand as a healthy option to fast food, riding on the success story of now-disgraced former spokesman Jared Fogle. Consumers' attitudes on health have shifted since, leading them to value local and wholesome ingredients over calorie counting.

As a result, Subway announced it would roll out an all-natural menu void of artificial flavors, colors and preservatives by this year.