If you've spent any time shopping for dog treats lately, you've probably noticed two words showing up everywhere: freeze-dried and air-dried. Both are marketed as "minimally processed." Both skip the fillers and high-heat cooking of conventional treats. But they're not the same process – and they don't produce the same treat.
Here's what actually happens to a piece of meat or fish on its way from raw ingredient to shelf-stable treat, and why it matters for what ends up in your dog's bowl.
What Is Freeze-Drying?
Freeze-drying (also called lyophilization) removes moisture through sublimation – the process of turning ice directly into vapor without ever passing through a liquid state. It happens in three stages:
- Freezing. The raw ingredient is rapidly frozen to very low temperatures. Freezing it fast creates smaller ice crystals, which cause less damage to the meat's cell structure than slow freezing would.
- Primary drying (sublimation). The frozen product goes into a vacuum chamber. Under that vacuum, the ice sublimates directly into water vapor, which is pulled away and removed. This step alone removes the vast majority of the moisture.
- Secondary drying. A small amount of gentle heat is applied under continued vacuum to release the last bit of bound moisture, bringing the final moisture content down to a very low percentage – the range that makes a treat shelf-stable without refrigeration or preservatives.
The key detail: there's no real heat-cooking step in freeze-drying. The ingredient stays frozen through the stage that removes almost all of its water, which is why freeze-dried treats keep their structure so well – bite into one and it's light, crisp, and almost airy, because the ice crystals left tiny pockets behind as they sublimated away. It's also why freeze-dried treats rehydrate almost instantly with a little warm water.
What Is Air-Drying?
Air-drying takes a slower, low-heat route. Instead of freezing and vacuum, it relies on controlled airflow and gentle warmth over an extended period – often a matter of days – to gradually pull moisture out of the ingredient.
- Preparation. The raw ingredient is cut or portioned for even drying.
- Controlled drying. It's placed in a temperature- and humidity-controlled environment where warm air circulates slowly and continuously, drawing moisture out from the surface inward.
- Moisture check and packaging. Once the product reaches a stable, safe moisture level, it's sealed for shelf-stable storage – no refrigeration needed.
Because air-drying uses time and airflow instead of extreme cold and vacuum, it produces a noticeably different result: a denser, chewier, jerky-like texture. That firmer bite is part of what makes air-dried chews satisfying for dogs who want something to work on
.
So Which One Preserves More Nutrients?
Both methods are considered gentle compared to conventional high-heat processing like baking or extrusion, which can damage heat-sensitive proteins, vitamins, and natural enzymes. Neither freeze-drying nor air-drying involves the kind of intense heat that does that damage.
The meaningful difference comes down to temperature. Freeze-drying never brings the product above freezing until the very final drying stage, and even then, the heat applied is mild. Air-drying uses warmth throughout the entire process, just at a controlled, moderate level rather than a high one. In practice, that means freeze-drying is the gentler of the two methods on paper – but air-drying still preserves far more of a food's natural nutrient profile than conventional cooking does, which is why it remains a genuinely minimal-processing option in its own right.
The texture difference is really the bigger practical story for pet owners: freeze-dried treats are light and crisp, air-dried treats are dense and chewy, and each suits different situations.
Freeze-Dried vs. Air-Dried at a Glance
| Freeze-Dried | Air-Dried | |
|---|---|---|
| How moisture is removed | Sublimation under vacuum, while frozen | Controlled airflow and gentle heat over time |
| Heat exposure | Minimal – product stays frozen through most of the process | Low, but present throughout |
| Texture | Light, crisp, airy | Dense, chewy, jerky-like |
| Best for | Quick training rewards, treats that rehydrate fast | Longer chewing sessions, dental engagement |
| Shelf stability | Shelf-stable without refrigeration | Shelf-stable without refrigeration |
Which Momentum Products Are Freeze-Dried vs. Air-Dried?
At Momentum Carnivore Nutrition, the split is simple: everything we make is freeze-dried, except our Icelandic fish chews, which are air-dried.
Freeze-dried:
- All single ingredient freeze-dried treats – hearts, livers, tenderloin, chicken breast, and more
- All Training Bites flavors
- All Natural Chews that aren't fish – pig ears, pig snouts, chicken and turkey necks, duck necks and heads, and bully sticks
Air-dried:
- Our full lineup of Icelandic fish chews – Diced Cod Bites, Cod Fingers, Short Cod Twists, Tiny Cod Twists, Short Cod Flatties, Short Cod Chews, Haddock Chews, Long Cod Chews, and Wolffish Flatties
FAQ
What's the difference between freeze-dried and air-dried dog treats? Freeze-dried treats are made by freezing the ingredient and removing moisture through sublimation under vacuum, while air-dried treats are made by slowly removing moisture with controlled airflow and gentle heat. The result is a light, crisp texture for freeze-dried treats and a denser, chewier texture for air-dried treats.
Is freeze-dried or air-dried better for dogs? Neither is inherently better – both are considered minimally processed compared to conventional high-heat treat making, and both are shelf-stable without refrigeration or artificial preservatives. The right choice depends on what you're looking for: freeze-dried treats work well for quick training rewards, while air-dried treats suit dogs who enjoy a longer, more substantial chew.
Do freeze-dried treats need to be rehydrated? No. Freeze-dried treats can be fed as-is, straight from the bag. Some pet owners choose to rehydrate them with warm water, goat's milk, or bone broth to soften them for puppies, senior dogs, or dogs with dental sensitivities, but it isn't required.
Are air-dried treats safe for dogs? Yes. Air-dried treats made from a single named protein with no added fillers or preservatives are a safe, natural option for most dogs. As with any chew, always supervise your dog and choose a size appropriate for their weight and chewing style.
Why don't freeze-dried and air-dried treats need refrigeration? Both processes remove the vast majority of moisture from the ingredient. Because bacteria and spoilage organisms need water to survive and multiply, reducing moisture to a very low level is what makes these treats shelf-stable at room temperature without artificial preservatives.
Which Momentum products are freeze-dried, and which are air-dried? All Momentum single ingredient treats, Training Bites, and natural chews (pig ears, pig snouts, chicken and turkey necks, duck necks and heads, and bully sticks) are freeze-dried. Our Icelandic fish chews are the one air-dried product in the lineup.
