What Rawhide Is Made Of, and What Is Done to the Hide

Rawhide is the inner layer of an animal hide, usually cattle, stripped of hair and fat with lime and other chemicals, then dried hard into a chew. We don't sell it. Whether rawhide is bad for dogs is a separate argument. This page is about the material.

You're probably holding one, or watching the dog hold one, and the bag has told you almost nothing. It isn't obliged to. Here is the hide, stage by stage, and what turned up when somebody put ten of these chews under a microscope.

Which layer of the hide it actually is

Rawhide is skin. Not muscle, not organ, not bone. Two board-certified veterinary nutritionists in Today's Veterinary Practice put rawhide chews at the chemically processed inner hide layer. Most often that's cattle, though pig, sheep and even water buffalo hides get used too.

Where it comes from is the other half of the answer. The American Kennel Club calls rawhide the leather industry's leftovers, with most hides taken straight from slaughterhouse kill floors into high-salt brines that slow decay.

So you're holding skin the leather trade had first call on. Hold onto that. Everything done to a hide after the brine has one aim — to make skin behave like a shelf-stable object.

What happens between the kill floor and the bag

Four stages sit between the animal and your dog, and every one takes something off.

Stage	What is done to the hide	What it leaves
Kill floor	Packed into a high-salt brine	Decay slowed for the journey
Liming	Soaked and treated with lime	Fat separating from skin
Dehairing	Chemical and physical effort	Hair off the hide
Finishing	Rinsed again, then dried	The chew you buy

That journey is longer than it looks. Most rawhide chews are manufactured in China, the AKC says, and brined hides can take weeks or months to reach a tannery at all. Standards differ by country, the veterinary review adds.

That's the usual route, not a spec sheet. Steps vary by plant, and your bag records none of them.

What the hide is treated with

The chemistry has a published list, even if your bag doesn't carry it. The veterinary nutritionists above name brine, degreasers, detergents, sodium bicarbonate, hydrogen peroxide and lime among the things a hide may be processed in. The stated jobs are to strip hair or fat, kill pathogens, and improve the appearance.

Appearance is on that list. Some of what a hide goes through is not preservation and not safety. It is cosmetic.

The same review notes scrap rawhide added for weight. Colors and flavors go in for palatability, and glues to hold a shape.

When a processing aid finally got named

You tend to learn what a hide was treated with only when a batch goes wrong.

Once, one of them got named in public. In June 2017 a manufacturer pulled several rawhide brands. Plants it used in Mexico and Colombia, and a supplier in Brazil, had been using a quaternary ammonium compound mixture as a processing aid. The recall notice describes an anti-microbial cleared for cleaning food processing equipment, and not cleared in the United States for making dog chews.

Notice whose words those are. The FDA posts a recalling company's own announcement as a public service, and says it doesn't endorse the product or the company. The illness figures inside it — very limited reports for the volume shipped, an unpleasant odor the commonest complaint — are the manufacturer counting its own harm. Which is the point. The record of what touched your dog's chew is whatever the maker chooses to say.

Why the bag can't tell you what's in it

The gap in the label isn't an oversight. It's the rule.

Extensively processed and compressed rawhides aren't considered food by the FDA, the same veterinary review explains. That puts them outside AAFCO registration and labeling rules altogether. No calorie statement is required, and no guaranteed analysis either.

That answers the question underneath your question. You can't read what a rawhide is made of off the pack, because nothing obliges it to say. Loose naming follows from the same gap, which is how beef hide and rawhide keep turning out to be the same thing.

What ten chews looked like under a microscope

Somebody ran the obvious experiment. Two researchers — one at the University of Florida's College of Veterinary Medicine — cut up ten dog chews, stained the sections, and read them under a light microscope.

The products were labeled rawhide, beef hide, beef chew or rawhide free. What the microscope found was not one tissue. Collagen, skeletal muscle, fat, plant material and starch all turned up across the set.

Four of the ten were two materials. A main chew roll, plus a separate filler coated onto it or laid between the layers, processed on its own. Eight products matched their own labels. Two sold as rawhide free looked like dermis, which is skin.

That's the closest anyone has come to answering this with an instrument instead of a label. For the cheap version, on the chew in your hand, the grain and the cut face settle it faster.

Why digestible never settles on an answer here

Digestibility is where the definition bites. Two lab studies put rawhide through simulated digestion and came out disagreeing. In the earlier one it finished far ahead of bone. In the later one it ran from 35 to 96 percent after the intestinal phase, the widest spread of any category there.

Now look at what the later study measured. Beef hide with chicken breast. Bone-shaped beef hide. Beef hide with wheat gluten. And twisted pig skin containing no rawhide at all, filed under rawhide because that is the shelf it came off.

So the number can't settle, because the thing being measured isn't one thing. Rawhide names a process, not a tissue. That process gets applied to whatever went in, and the label survives the substitution.

That cuts against us as much as for us, and we'd rather say it than let you find it. The head-to-head belongs to bully sticks versus rawhide, which runs the numbers properly. Read it knowing we sell bully sticks and nothing on this page.

The part the material never changes

Material is the smaller variable. A hide chew and a dried muscle come apart differently, and they end the same way: as a piece small enough to go down whole. Hide, dried muscle, collagen, tripe — a bully stick included.

So the habit is dull, and it's the one we teach for everything we sell. Stay in the room while your dog works. When the piece would fit whole in their mouth, take it, hand over a treat, and throw the end away.

Two dogs want a vet in this conversation first: one that has already had an obstruction, and one on a prescription or elimination diet. Ask your vet before the chew, not after. And if a piece is already down, that's a call you make today.

Rawhide FAQ

What animal is rawhide made from?

Cattle, most of the time. Rawhide chews are made from the inner hide layer, most often from cows, though pig, sheep and even water buffalo hides get used as well. It's the same raw material stream that feeds the leather trade, so the species follows whatever the tanneries are running.

Is rawhide bleached?

It's whitened more often than bleached in the household sense. Hydrogen peroxide sits on the published list of things a hide may be processed in, alongside brine, degreasers, detergents, sodium bicarbonate and lime. Some of that work removes hair and fat. Some of it is there to improve appearance, and nothing on your bag separates the two for you.

Is rawhide a byproduct of the leather industry?

Yes, and the AKC puts it plainly: rawhide chews are made from the leather industry's leftovers. Hides come off slaughterhouse kill floors into high-salt brine, then travel to a tannery for liming and dehairing. The chew aisle sits downstream of the tannery, not of the butcher. Everything else — the brine, the lime, the chemistry, the silence on the label — follows from that one fact.

Rawhide is skin, run through a tannery and dried, under a label that owes you nothing. We don't stock it. Know the material and the chew in your hand stops being a mystery. The chew quiz is there if you'd rather start from your dog.