NEW YORK – “Our biscuit is not the same one it was a year ago,” and customers can’t necessarily tell, Stan Frankenthaler, executive chef at Dunkin’ Brands Group, told Bloomberg BusinessWeek. The company has been using a “stepped approach” to reducing salt and sugar: “Restaurants are wanting to do it a little bit behind the scenes,” he told the news source.

In fact, what QSRs such as Dunkin’, Subway and Au Bon Pain don’t want to do — while making their fare healthier — is scare customers away with words such as “low sodium” and “diet.”

Here’s some of the menu tweaks the companies have been making:

Frankenthaler lowered the salt in Dunkin’s English muffins and biscuits by using different combinations of baking powder and cream of tartar, reports the news source. He’s also cut sugar from Coolatta drinks by using riper fruits.

Au Bon Pain first cut sodium levels in its chicken noodle soup by 23% in 2008. In 2012, it cut the salt again by 8%, and another 7% to 650 mgs this past June. The news source adds that chef Stefano Cordova “used mushroom powder to replace some of the salt, and he smokes and roasts vegetables for a more flavorful broth. His long-term goal is to lower sodium in Au Bon Pain’s bread by about 20 percent.”

Subway began lower sodium levels in its bread in 2009 as well as in its meats and sauces. “When you hear less sodium, your mind hears less taste,” Elizabeth Stewart, Subway’s marketing director, told the news source, adding that the company has relied on this change over time instead of all at once so that consumer palates could adjust.

However, not all consumers have been fooled by minor tweaks to their favorite foods. In 2012, the news source reports that Au Bon Pain replaced its 550-calorie cinnamon roll with a 480-calorie version that omitted the sweet, sugar glaze. Customers made their thoughts known to Chef Cordova, and two months later, the glaze returned.

Sometimes, Cordova told the news source, “It’s a sin to take sugar away.”