What's Really Inside a Hot Dog?

At baseball stadiums, holiday cookouts, and in the dorm rooms of broke college students everywhere, hot dogs have become a staple meal. Each time we wield a wiener, however, rumors and innuendo over the food’s manufacturing integrity come flooding to the surface. Is this tubed meat made from monkey brains? Is there an underground network of hot dog companies that slip in cows’ feet as a filler? Why are hot dogs so nutritionally suspect?

Fortunately, most of your worst fears may be unfounded. Except for the feet. More on that in a moment ...

Ever since Upton Sinclair uncovered the misdeeds of the meat industry in the early 1900s, the government has kept a close eye on animal product manufacturing methods. Gone were the sawdust and dog and horse parts that previously made up hot dogs and other highly-processed meats. Companies had to obey strict preparation guidelines that significantly reduced the chances of foodborne illness and forced them into using transparent food labels.

Hot dogs are no exception, though you might have to decipher some of the language on the label to understand what you’re really biting into. Beef, pork, turkey, or chicken dogs originate with trimmings, a fanciful word for the discards of meat cuts that are left on the slaughterhouse table. That usually means fatty tissue, sinewy muscle, meat from an animal’s head—not typically a choice cut at Morton’s—and the occasional liver.

This heap of unappetizing gristle is pre-cooked to kill bacteria and transformed into an even more unappetizing meat paste via emulsion, then ground up and pushed through a sieve so that it takes on a hamburger-like texture. A number of things could be added at this point, including ascorbic acid (vitamin C) to aid in curing, water, corn syrup, and various spices for taste. Less appetizing ingredients can also include sodium erythorbate, which the National Hot Dog and Sausage Council swears is not actually ground-up earthworms:

"In contrast to a popular urban legend, erythorbate is NOT made from earthworms, though the U.S. Department of Agriculture reports receiving many inquiries about erythorbate’s source. It is speculated that the similarity in the spelling of the words 'erythorbate' and 'earthworms' has led to this confusion."

Got that? No worms. After another puree, the meat paste is pumped into casings to get that familiar tubular shape and is then fully cooked. After a water rinse, the hot dog has the cellulose casing removed and is packaged for consumption. While not exactly fine dining, it’s all USDA-approved.

More skittish consumers should pay attention to packaging labels. If you see “variety meats” or “meat by-products,” that means the hot dog probably has heart or other organ material in the meat batter. Additives like MSG and nitrates are also common, though all-natural dogs usually skip any objectionable ingredients. If it’s labeled “all beef or “all pork,” you can be assured it's coming from muscle tissue of that animal, not organs.

But those trimmings? By definition, they can contain a lot of things that come off an animal, including blood, skin, and even feet. It’s all edible, though some might object to the very idea of eating random cow or pig parts. At least none of it is actual human meat, as some people feared when a Clear Lab food advocacy test in 2015 showed 2 percent of hot dog samples contained human DNA. That was more likely due to human error and trace amounts of hair or fingernails making their way into the batch, not a worker falling into the vat. Enjoy!

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