Dairy producers are calling for a crackdown on the almond, soy and rice "milks" they say are masquerading as the real thing and cloud the meaning of milk for shoppers.

And a group that advocates for plant-based products, the Good Food Institute, countered by asking the Food and Drug Administration this week to say foods can use terms such as "milk" and "sausage," so long as they're modified to make clear what's in them.

It's the latest dispute about what qualifies a food as authentic, many of them stemming from developments in manufacturing practices and specialized diets.

DiGiorno's frozen chicken "wyngz" were fodder for comedian Stephen Colbert.

An eggless, vegan spread provoked the ire of egg producers by calling itself "mayo."

And as far back as the 1880s, margarine was dismissed as "counterfeit butter" by a Wisconsin lawmaker.

The U.S. actually spells out the required characteristics for a range of products such as French dressing, canned peas and raisin bread. It's these federal standards of identity that often trigger the food fights.