What are animal protein powders made of?

December 16, 2025 •

3 min read

Over 60% of all protein powders sold in the market are derived from animal sources, primarily dairy. These powders are created through a series of processes that extract and isolate protein from raw animal-based materials, turning them into a concentrated, shelf-stable supplement.

Quick Summary

Animal protein powders are derived primarily from dairy (whey and casein), eggs, and bovine connective tissues (collagen). Each source undergoes specific processing to extract, concentrate, and dry the protein into a fine powder, often with added flavors and ingredients for palatability.

Key Points

Whey Protein: A fast-absorbing milk protein, derived as a byproduct of cheese production and filtered for different concentrations.
Casein Protein: A slow-digesting milk protein that comes from the solid curds separated during cheesemaking.
Egg Protein: A dairy-free alternative made from isolated and dried egg whites, providing a complete amino acid profile.
Collagen Protein: Sourced from animal connective tissues and used primarily for joint and skin health, not a complete protein.
Production Process: Involves separating protein from its animal source, followed by filtration, drying, and often the addition of flavorings and other ingredients.

The Primary Animal Sources of Protein Powder

Animal protein powders are widely used for muscle building, recovery, and daily protein supplementation. The ingredients depend on the specific type of protein, with the most common ones derived from milk, eggs, and connective tissues. Understanding the origin helps consumers make informed choices based on dietary needs and potential sensitivities, such as lactose intolerance.

Whey Protein

Whey protein is arguably the most popular animal protein powder, known for its fast absorption and high concentration of branched-chain amino acids (BCAAs). It is a byproduct of the cheesemaking process. The manufacturing process involves several steps:

Milk Pasteurization: Raw milk is first pasteurized to kill harmful bacteria.
Coagulation: Enzymes or an acid are added to the milk, causing it to coagulate and separate into solid curds (casein) and liquid whey.
Draining: The liquid whey is drained from the curds and sent for further processing.
Filtration: The liquid whey is filtered to remove fat, lactose, and other non-protein components. This results in different concentrations, from whey protein concentrate (WPC) to whey protein isolate (WPI), which is more filtered and has a higher protein content.
Drying: The purified liquid is finally spray-dried into a powder.

Casein Protein

Casein is the other major protein found in milk, making up about 80% of its content. Unlike whey, casein is slow-digesting, making it ideal for sustained amino acid release. Casein protein is the solid curd that is separated from the liquid whey during the cheesemaking process. The curds are then dried and processed into a fine powder.

Egg Protein Powder

Egg white protein is a dairy-free animal protein option, created by isolating the protein from egg whites. It offers a complete amino acid profile and is typically well-tolerated by individuals with dairy sensitivities. To produce the powder, egg whites are separated from the yolks, pasteurized, and then spray-dried into powder form.

Collagen Protein

Collagen protein is a type of animal protein derived from the connective tissues, bones, and hides of animals like cows (bovine) or fish (marine). It is not a complete protein and is used for different purposes than traditional protein powders, often targeting joint and skin health rather than muscle synthesis.

The Role of Additives and Processing

Beyond the raw protein source, many animal protein powders contain additional ingredients. These are added to improve taste, texture, and nutritional profile. Common additives include:

Sweeteners: Both natural (stevia) and artificial (sucralose) sweeteners are used to improve flavor.
Flavorings: Artificial and natural flavorings mask the often-bland or bitter taste of the raw protein powder.
Emulsifiers and Thickeners: Ingredients like lecithin, xanthan gum, or guar gum are added to improve mixability and texture.
Vitamins and Minerals: Some manufacturers fortify their powders with extra vitamins and minerals for added nutritional benefit.
Enzymes: Digestive enzymes like proteases are sometimes included to aid in the digestion and absorption of the protein.

Comparison of Common Animal Protein Powders


Feature	Whey Protein	Casein Protein	Egg Protein	Collagen Protein
Source	Milk (Liquid Whey)	Milk (Solid Curds)	Egg Whites	Animal Connective Tissues
Digestion Speed	Fast	Slow	Medium	Fast
Best For	Post-workout recovery, muscle building	Before bed or sustained release	Dairy-free complete protein source	Joint and skin health
Complete Protein?	Yes	Yes	Yes	No
Lactose Content	Present in concentrate, minimal in isolate	High	None	None
Common Use	Shakes, smoothies	Pudding, shakes	Shakes, baking	Shakes, coffee, baked goods

Conclusion

Animal protein powders are made from a range of sources, with the most common being whey and casein from milk, and protein isolated from egg whites. The manufacturing process for each involves isolating the protein and drying it into a powder, often with other ingredients added for flavor and texture. Whey protein is ideal for rapid absorption after a workout, while casein provides a slow, steady release of amino acids. Egg protein offers a complete, dairy-free alternative, and collagen is primarily targeted for joint and skin health. Choosing the right animal protein powder depends on your specific dietary needs, fitness goals, and any sensitivities you may have.

For more in-depth information on protein powder manufacturing, resources like the Colorado State University Food Source Information provide excellent details on how dairy-based protein powders are made.

Frequently Asked Questions

Whey protein is a fast-digesting milk protein, while casein is a slow-digesting milk protein. Whey is quickly absorbed for post-workout recovery, whereas casein provides a sustained release of amino acids, often used before bed.

Not all animal protein powders are suitable for individuals with lactose intolerance. Whey protein concentrate contains lactose, but whey protein isolate is highly filtered to remove most of the lactose. Egg protein and collagen protein are both dairy-free alternatives.

Collagen protein powders are made from the connective tissues, bones, and hides of animals, such as cows (bovine) or fish (marine). These tissues are processed to extract the collagen protein.

Whey protein is made during cheesemaking. Milk is curdled and separated into solid curds (casein) and liquid whey. This liquid whey is then pasteurized, filtered to remove fats and lactose, and finally spray-dried into a powder.

Many animal protein powders contain added ingredients for improved flavor, texture, and mixability. These can include sweeteners, flavorings, thickeners, and sometimes vitamins and digestive enzymes.

Most animal protein powders, such as whey, casein, and egg protein, are considered 'complete' proteins because they contain all nine essential amino acids. Collagen protein, however, is not a complete protein.

Someone might choose egg protein if they have a dairy allergy or lactose intolerance, as it is a dairy-free animal protein source. It also provides a complete amino acid profile.