Freeze-Dried vs. Kibble: Protein Quality Compared

Kristina Voltin
Jul 9
12 min read

Updated: Nov 21

When choosing between freeze-dried raw food and kibble for your dog, the quality of protein is a key factor. Freeze-dried food retains more nutrients due to minimal processing, while kibble undergoes high-heat extrusion, which can degrade protein and nutrient quality. Here's the main takeaway:

Freeze-Dried Raw Food: Uses whole meats, preserves natural enzymes, and has a higher digestibility (up to 99%). It typically avoids fillers and synthetic additives, making it easier for dogs to absorb nutrients.
Kibble: Relies on meat meals and by-products, with added fillers like corn or soy. High-heat processing can damage protein and amino acids, requiring synthetic nutrients to compensate.

Quick Comparison

Factor	Freeze-Dried Raw Food	Kibble
Processing Method	Low-temperature freeze-drying	High-heat extrusion
Protein Sources	Whole meats, organ meats	Meat meals, by-products
Nutrient Retention	Preserves natural vitamins/enzymes	Requires synthetic additives
Digestibility	Up to 99%	Around 79%
Fillers/Additives	Minimal	Often includes grains, fillers

For dogs with sensitivities or specific dietary needs, freeze-dried raw food may offer a simpler, more nutrient-rich option. However, kibble is more affordable and widely available. Consult your vet to choose the best option for your dog's health and lifestyle.

What to Feed Your Dog - Raw, Freeze Dried, or Kibble?

Freeze-Dried Raw Food: Protein Quality and Benefits

Freeze-dried raw food retains the natural structure of proteins and essential nutrients through a gentle processing method that stands out compared to traditional manufacturing techniques.

How Freeze-Drying Preserves Protein

Freeze-drying works by removing moisture at low temperatures under a vacuum (a process called sublimation), which helps retain up to 97–98% of the nutrients while maintaining protein bioavailability [3][4]. This method ensures that proteins remain in their natural form, making them easier for your dog's digestive system to process.

Another advantage of the low-temperature process is that it preserves natural enzymes. These enzymes play a vital role in digestion by breaking down complex proteins into amino acids that the body can use [2]. By keeping the protein structure intact, freeze-dried raw diets provide nutritional benefits that are hard to match.

Nutritional Benefits of Freeze-Dried Raw Food

Freeze-dried raw food offers high-quality protein from whole meats with minimal processing. Essential amino acids like methionine (93–95%), tryptophan (up to 98%), and arginine (94–96%) in these foods have digestibility rates exceeding 90% [8].

Compared to traditional kibble, freeze-dried raw food contains significantly more protein - up to three times as much [7]. The inclusion of raw meat and organ meat supplies essential amino acids for muscle repair and maintenance, along with key nutrients like vitamins A, B, and iron that support energy production and metabolic functions [6]. The higher protein levels, combined with the absence of unnecessary carbohydrates, promote a healthy weight and a more efficient metabolism [6].

Raw diets also have a digestibility rate of 90–95% [6], meaning nutrients are absorbed more effectively while reducing strain on the digestive system. This often leads to smaller, firmer stools [6]. Additionally, the lack of fillers in these diets further enhances nutrient absorption.

No Fillers, Better Digestion

Freeze-dried raw food is free from synthetic additives and fillers, making it easier for dogs to digest and absorb nutrients. The freeze-drying process naturally inhibits bacteria and mold, providing a longer shelf life without the need for artificial preservatives [3][5].

Without fillers, dogs receive pure nutrition without unnecessary ingredients that could disrupt digestion. Many freeze-dried raw foods also include low-glycemic vegetables, which help regulate blood sugar and support weight management by promoting a healthy metabolic rate [6]. The natural preservation of flavors and aromas also makes these diets more appealing, particularly for dogs with sensitive stomachs or those needing easily digestible nutrition.

This form of food closely resembles a dog's ancestral diet [3], delivering nutrients in a way that aligns with their natural digestive systems. By providing high-quality, bioavailable proteins, freeze-dried raw food supports both immediate health and long-term metabolic balance, contributing to a healthier, more active life for your dog.

Kibble: Protein Content and Processing Effects

Both kibble and freeze-dried raw food aim to meet nutritional standards, but the heavy processing involved in kibble production can significantly impact the quality of its protein compared to less processed alternatives.

How Kibble Production Affects Protein

Kibble is made using an extrusion process that subjects proteins to extreme temperatures - typically between 302°F and 392°F (150°C to 200°C) [9]. These high temperatures cause protein denaturation, breaking the weak bonds that maintain the protein's natural structure. Once denatured, the protein's structure cannot return to its original form. While this process can make lower-quality proteins easier to digest, it can also reduce the nutritional benefits of higher-quality proteins [9].

Additionally, high-temperature cooking triggers Maillard reactions, which can decrease lysine levels by up to 80% and impair other essential amino acids [10][12]. This process doesn't just affect proteins - it also alters carbohydrates and fats, further reducing the overall nutritional value of the food [11].

Common Protein Sources in Kibble

The protein in kibble often comes from rendered meats, meat meals, and plant-based sources [1]. These ingredients undergo extensive processing, which can impact both their nutritional value and digestibility. Animal proteins generally contain higher levels of essential amino acids, while plant-based options like peas and lentils are usually less digestible and lack some amino acids [1][13]. To keep costs down, many manufacturers rely on meat meals and by-products instead of whole meats.

Fish has become a more popular protein choice in recent years, offering health benefits and easier digestibility. It’s also a good alternative for dogs with sensitivities to common proteins like chicken or beef [13]. However, the heavy processing and ingredient choices in kibble often lead to a product that doesn’t provide the highest quality protein.

Fillers and Additives in Kibble

The ingredients used in kibble also affect its nutritional value. Many manufacturers include fillers - ingredients like corn, wheat, soy, and rice bran - that add bulk but offer little to no nutritional value [15]. These fillers can dilute the food's overall quality. Dry dog foods often contain 30–60% carbohydrates, primarily from starch, which is far from a dog’s natural dietary needs and can impact metabolic health [1].

Premium Dog Food Ingredients	Standard Kibble Ingredients
Whole, named meats (turkey, chicken, lamb, beef, fish)	Animal by-products and meat meals
Natural preservatives (vitamin E, rosemary)	Synthetic preservatives (BHA, BHT, ethoxyquin)
Fruits and vegetables	Corn, wheat, and soy fillers
Healthy fats (chicken fat, fish oil)	Sugar and artificial sweeteners

Artificial additives and preservatives are another concern. These are often added to improve taste, color, and shelf life [14]. However, some synthetic additives like BHA, BHT, and ethoxyquin have been linked to health risks, including cancer and allergic reactions [14]. High-heat processing can also degrade or destroy vitamins, which is why synthetic vitamins are added back into the food after cooking [10]. While this supplementation can restore some nutrients, it cannot repair the damaged protein structure or replace natural enzymes lost during production.

In short, the combination of high-temperature processing, lower-quality protein sources, and fillers results in kibble that meets basic nutritional standards but may not provide the quality of protein or nutrients needed for optimal health.

Freeze-Dried vs. Kibble: Direct Comparison

Let’s take a closer look at how freeze-dried raw food and kibble stack up when it comes to protein quality. The way each is processed has a major impact on the nutritional value and, ultimately, your dog’s health.

Comparison Table

Factor	Freeze-Dried Raw Food	Kibble
Processing Method	Low-temperature freeze-drying preserves natural structure	High-heat extrusion damages protein integrity
Protein Sources	Whole meats and organ meats, often from single sources	Relies on meat meals and by-products
Nutrient Retention	Retains natural vitamins, minerals, and enzymes	Significant nutrient loss, requiring synthetic additives
Digestibility	Highly digestible, mimicking a natural diet	Lower bioavailability due to heavy processing
Fillers and Additives	Minimal, made with natural ingredients	Often includes grains like corn, wheat, and soy
Amino Acid Profile	Preserves a complete amino acid profile	Processing can limit essential amino acid availability

Freeze-dried raw food undergoes a low-temperature process that removes moisture while keeping proteins and enzymes intact. On the other hand, kibble is made using high-heat extrusion, a process that breaks down protein structures and reduces nutrient availability. This stark difference in processing methods plays a big role in the food's digestibility and nutritional value.

In freeze-dried food, the protein often comes from high-quality, whole meat sources, typically from a single ingredient. In contrast, kibble tends to use processed proteins, such as meat meals and by-products, which can affect both digestibility and the amino acid profile your dog receives. Research has shown that raw diets are easier for dogs to digest and support better metabolic health [17][18]. Dogs fed raw diets even had healthier gut bacteria, with higher levels of fecal Bacteroidetes and lower levels of Firmicutes, compared to dogs on extruded diets [18].

Another advantage of freeze-drying is its ability to preserve key enzymes and micronutrients, which can improve nutrient absorption. Kibble, on the other hand, often contains more carbohydrates and requires synthetic vitamins to make up for nutrients lost during processing. These synthetic additions, while helpful, can’t fully replicate the natural nutrient profile found in freeze-dried options.

"Our freeze-dried raw dog food is made with high-quality ingredients and preserved using advanced technology that retains the nutritional integrity of the food. This means that your dog will benefit from a nutrient-dense meal that can improve their overall health and wellness."Dr. Marty's pet nutrition expert

Ultimately, freeze-dried raw food offers a more natural and nutrient-rich option, while kibble relies on heavy processing and additives to meet nutritional needs. The choice between the two can significantly impact your dog’s health and well-being.

How Protein Quality Affects Metabolic Health

Proteins that are easy to digest and of high quality play a crucial role in supporting nutrient absorption, managing weight, resisting diseases, and boosting metabolism - all of which contribute to better overall health.

Complete Proteins and Their Benefits

Complete proteins contain all the essential amino acids your body needs for optimal metabolic performance. The specific protein requirements can vary based on factors like age and health conditions. These proteins are quickly absorbed by the body, aiding vital metabolic processes and promoting overall well-being.

"Proteins are important in the formation and maintenance of muscle, skin, hair, nail, cartilage, tendons, and ligaments. Protein in dog food also assists with hormone, antibody, and blood formation." – Tiffany Tupler, DVM, CBCC-KA [1]

High-protein diets can help burn more calories, preserve lean muscle mass, and reduce body fat [20]. For older dogs who need to either lose weight or build muscle, veterinarians often suggest diets with protein levels between 28% and 32% [19].

Animal-based proteins like chicken and turkey usually offer a richer amino acid profile and are often easier for dogs to digest compared to some plant-based sources. However, the way these proteins are processed matters significantly. For instance, chicken meal doesn’t provide the same nutritional value as whole chicken [19].

When proteins are minimally processed, they retain more of their nutritional integrity, further enhancing their metabolic benefits.

The Role of Minimally Processed Proteins in Health

Minimally processed proteins, such as those found in freeze-dried foods, maintain their natural structure better than heavily processed options like kibble. This preservation translates to improved digestibility and nutrient absorption.

Research shows that raw diets can achieve protein digestibility rates as high as 99.3%, compared to just 79.5% for processed foods [17]. A 2024 study also highlighted that raw diets may reduce gut inflammation markers, likely due to their lower starch content - less than 1% in raw diets versus roughly one-third in kibble [17].

Other benefits include healthier blood lipid levels. For example, a 2018 study found that dogs on raw diets had lower blood triglycerides, while those on extruded kibble showed higher serum triglyceride levels compared to dogs fed grain-free roasted, refrigerated, or raw diets [17] [18].

Minimally processed proteins also reduce metabolic strain, supporting better gut health and lipid profiles over time. A study published in Frontiers in Veterinary Science followed 55 healthy dogs over a year and found that those on raw diets had altered fecal bacterial composition and lower inflammation markers, indicating improved gut health and nutrient absorption [17].

"Protein is the bedrock of nutrition for both humans and dogs. For dogs, the correct amount of protein can help their bodies function optimally." – The Honest Kitchen [19]

Freeze-dried raw products, which preserve natural enzymes and nutrients, make digestion less taxing and improve nutrient uptake. This leads to a more efficient metabolism and better overall health [16].

Loyal Saints: Premium Freeze-Dried Raw Nutrition

Loyal Saints offers a premium freeze-dried raw dog food option designed to support dogs at every life stage. Their focus is on delivering high-quality protein while promoting metabolic health and overall well-being.

What Sets Loyal Saints Apart

Loyal Saints uses human-grade, all-natural ingredients with no additives or fillers. Their recipes, approved by veterinarians and aligned with AAFCO standards, meet strict nutritional requirements [21].

The freeze-drying process is a key feature. It helps lock in essential nutrients, enzymes, and proteins that can be lost during traditional manufacturing. This approach not only preserves the food's natural flavor, aroma, and texture but also ensures a nutrient-rich and appealing meal for dogs [22].

Their grain- and starch-free recipes deliver a high-protein diet that’s easy to digest and packed with energy [22]. Each formula includes a thoughtful mix of meat, fruits, vegetables, natural preservatives, vitamins, minerals, antioxidants, and fish oil. The retained natural enzymes aid digestion and enhance nutrient absorption [22].

"At Loyal Saints, we believe that healthy ingredients lead to happy, vibrant lives for our beloved pets." - Loyal Saints Pets [21]

Another big perk? Loyal Saints' products have a shelf life of up to 24 months when stored properly, making them a convenient choice for pet owners without sacrificing quality [22]. This extended shelf life ensures the food maintains its nutrient integrity while supporting your dog’s metabolic health.

Promoting Health and Vitality

Thanks to the freeze-drying process, Loyal Saints’ formulas deliver high-quality protein that helps dogs build lean muscle and maintain overall vitality [21]. The inclusion of whole, natural ingredients provides nutrient-dense proteins, while fruits and vegetables support digestion and help manage allergies [21].

Choosing the Right Food for Your Dog

When deciding between freeze-dried raw food and kibble, it’s important to consider your dog’s age, health, and nutritional needs. As mentioned earlier, minimal processing in freeze-dried food helps retain essential nutrients, while kibble’s high-heat extrusion can reduce nutrient quality [16]. This difference in processing directly impacts the overall protein quality and nutritional value of your dog's diet.

While freeze-dried raw food may come with a higher price tag, its nutrient density often means you’ll need to feed your dog less, which could balance out the cost over time [16].

For dogs with sensitivities or allergies, freeze-dried diets are particularly appealing due to their simple ingredient lists and absence of fillers. Holistic Animal Wellness Specialist Ruth Hatten notes:

"Freeze-dried raw pet food can be an excellent choice for pets with allergies. Since freeze-dried diets usually contain fewer ingredients and eliminate unnecessary fillers, preservatives, and additives, they are less likely to trigger allergic reactions." [23]

Another advantage of freeze-dried raw food is its superior digestibility. Studies show raw diets can achieve up to 99.3% protein digestibility, compared to 79.5% for kibble [17].

Key Points to Remember

Here’s a quick breakdown of the main differences:

Protein Quality and Digestibility: Freeze-dried raw food retains beneficial enzymes that aid digestion, thanks to minimal processing. In contrast, kibble’s high-heat preparation can lead to nutrient loss [16].
Sensitive Stomachs and Allergies: Dogs with digestive issues or allergies may thrive on freeze-dried diets due to their simpler ingredient profiles and natural preservation methods. Rehydrating the food can also make it easier to digest [23].
Shelf Life and Storage: Both options are shelf-stable, but freeze-dried raw food often lasts longer - up to one to two years when stored properly - while maintaining better nutrient retention [23].
Taste Appeal: The freeze-drying process preserves the natural flavors and aromas of raw meat, making it a favorite among picky eaters [16].

Ultimately, your dog’s specific needs should guide your choice. Consult your veterinarian for recommendations tailored to your pet’s health and nutritional goals [2].

FAQs

How does freeze-drying affect the nutritional quality of dog food compared to kibble?

The freeze-drying process is a low-temperature method that helps keep nutrients, vitamins, and enzymes intact in dog food. This gentle technique preserves around 97–98% of the original nutrients, ensuring your dog enjoys a meal packed with nutrition.

On the other hand, kibble is produced using high heat and extrusion, which can lead to a significant loss of nutrients - often retaining just 60–75% of the original nutritional content. As a result, freeze-dried dog food offers a more nutrient-packed alternative, promoting your dog's metabolic health and overall well-being.

What are the health benefits of freeze-dried raw food for dogs with allergies or sensitivities?

Freeze-dried raw food is an excellent choice for dogs dealing with allergies or sensitivities. It’s easy on their digestive system and avoids common triggers like fillers, artificial flavors, and preservatives - ingredients often linked to allergic reactions and stomach troubles.

What’s more, these diets preserve natural enzymes and probiotics, which play a key role in supporting gut health. They help improve nutrient absorption and ease digestive issues, making this type of food a smart option for dogs with sensitive stomachs or food-related problems. The result? A happier, healthier pup with improved overall well-being.

How does freeze-dried raw food compare to kibble in supporting a dog's metabolic health?

Freeze-dried raw dog food stands out as a great option for supporting your dog's metabolic health. Its minimal processing helps preserve natural nutrients, vitamins, and enzymes, making it easier for dogs to digest and absorb the essentials they need. This can lead to better energy use and improved overall well-being.

Another advantage is the higher content of high-quality, bioavailable protein in freeze-dried raw diets. This type of protein supports muscle health, keeps metabolism functioning smoothly, and aids in various biochemical processes. With balanced, nutrient-packed meals, freeze-dried raw food can help your dog stay healthy and energetic at any stage of life.