10 Gross Food Ingredients You Didn’t Know You Were Eating

Updated: Apr. 15, 2021

Pink slime is just the beginning. Here are more gross ingredients that might be in your next bite of food.

Close-up photo of raw minced meat / mince /ground meat. Textured food background.
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Concerns over this chemical came to a head in 2012, when there was so much backlash over ammonia-treated “finely textured beef” (aka “pink slime”) that it was taken out of school lunches. Regardless of the fact that you probably don’t like the idea of ingesting a product more commonly used to clean floors, research shows ammonia in beef is safe. Ammonia may also show up in small amounts in peanut butter, chips, and other foods, and the truth is, processed foods contain all sorts of gross-sounding ingredients that have been deemed safe by the FDA and USDA. Here’s a rundown.

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Human or hog hair, or duck feathers

Mass-produced baked goods often contain L-cysteine, an amino acid that helps strengthen the dough. Sounds innocent enough, but you might want to pay attention if you’re vegan. Most of the time it’s made from duck or goose feathers, though some companies have used human hair, or pig bristles and hooves. L-cysteine can be made synthetically, but it’s expensive, so you might want to call up a company if you’re worried about animal products. Don’t miss these disgusting (and dangerous) things you didn’t know you were eating.

Lactobacillus bacteria colonies. A gloved hand holding a Petri dish that contains Gram-positive lactobacillus bacteria grown on agar. Lactobacillus is a common yogurt probiotic.

Sprayed-on viruses

Sounds a bit backward, but some companies add viruses to meat, poultry, and egg products to keep consumers healthy. These “bacteriophages” would prey on dangerous bacteria like Listeria, and the first ones were cleared as safe by the FDA in 2006. Since then, other cocktails of viruses have been given a thumbs up. “Virus” sounds scary, but the products are generally recognized as safe.

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Insect dye

The female Lac beetle gives us the ingredient shellac—sometimes called “confectioner’s glaze” in food—used to make candy and fruit (and furniture) shiny. Carmine (or cochineal), commonly used as a red food coloring for fruit juices and candy, is made from the shells of desert insects. Feeling squeamish? Hunt down red products that are made with Red #40 instead—that dye comes from coal, not bugs. Find out which things you touch every day but might be toxic.

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Wood pulp

An additive called cellulose is derived from tiny pieces of plant fibers and wood to make some types of low-fat ice cream seem more creamy. It’s also used to prevent some shredded cheese from clumping.

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Fish bladders

There might be more to your Riesling than grapes. Winemakers usually use extra ingredients during the “fining” process, when they make the wine less cloudy. One popular method uses isinglass, a gelatin that comes from the swim bladders of sturgeons. If it’s any consolation, swim bladders hold air, not urine. Make sure you know which 26 foods you should never buy again.

Sheep fur. Wool texture. Closeup background

Sheep wool grease

Lanolin is a waxy yellowish substance that sheep produce to wick water away so their coats don’t get soaked through. It also happens to be both a good source of vitamin D and a waste product (read: cheap) in wool production. Companies use it in vitamin D-fortified products, as well as in chewing gum to improve its texture.

Rat in the house on the floor
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Rodent hairs

While food manufacturers don’t go around sprinkling rat fur into your food, it can be just about impossible to keep those pests away. The FDA does allow a certain amount of rat hair into your food, but it caps it at limits you would probably never notice. Ground cinnamon, for instance, can have up to 11 hairs per 50 grams, but chocolate will be tossed if a set of 100-gram samples has an average of one or more hairs. Beyond the ingredients themselves, these 11 cooking mistakes could make your food toxic.

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Sawdust smoke

Oh, you thought “liquid smoke” was just a name? Nope, it’s exactly what it says. Manufacturers burn sawdust byproducts, then trap the condensation droplets from its steam, condense it, and bottle it up. Some people fear that eating straight smoke could be a carcinogen, but it’s considered safe in moderation. Learn about these other toxic ingredients you use every day.

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Animal cartilage

Maybe you’ve heard the not-so-new news: Gelatin (aka the stuff that males Jell-O all wobbly) is made by boiling cartilage, skin, and bones from animals. If that makes you lose your appetite, it’s not just Jell-o you should be scrunching your nose at. The ingredient is also in marshmallows, Starbursts, gummies, and other sweets. Next, check out these 50 secrets food manufacturers don’t want you to know.

Reader's Digest
Originally Published in Reader's Digest