What Is the Process of Protein Concentrate Manufacturing?

November 27, 2025 •

5 min read

The global plant-based protein market was projected to reach $14.5 billion by 2025, driving innovation in protein concentrate manufacturing. The process of protein concentrate production varies significantly depending on the source material, with methods ranging from physical separation to complex chemical processes involving filtration and precipitation.

Quick Summary

Protein concentrate manufacturing involves separating and concentrating protein from a source material, such as milk or legumes, by removing water, carbohydrates, and fats. Key industrial methods include membrane filtration for dairy and wet extraction or dry fractionation for plant-based sources, followed by a final drying step.

Key Points

Source-Dependent Process: The method for producing protein concentrate depends on the source material, with dairy often using membrane filtration and plant-based proteins using wet or dry extraction techniques.
Membrane Filtration for Dairy: Dairy proteins (whey, casein) are concentrated using ultrafiltration (UF) and diafiltration (DF), which physically separate protein from lactose and minerals using semipermeable membranes.
Wet Extraction for Plant Proteins: Plant-based concentrates often rely on wet extraction, using chemicals like acid or alkali to adjust pH, causing the protein to dissolve and then precipitate for collection.
Dry Fractionation as a Sustainable Alternative: Dry fractionation, such as air classification, physically separates plant protein from starch and fiber without water or chemicals, making it more eco-friendly but typically yielding a lower protein concentration.
Purpose of Concentration: The core purpose of all these processes is to increase the protein content of a source material by removing water, fats, and carbohydrates, resulting in a protein-rich powder.
Final Product Quality Varies: The final protein concentrate's purity, composition, and functional properties are directly influenced by the specific manufacturing process employed.

Understanding the Raw Materials

Protein concentrates are produced from a wide range of source materials, both animal- and plant-based. The choice of raw material fundamentally dictates the extraction method. Animal sources predominantly involve whey from cheese production, while plant sources include a variety of legumes like soy, peas, and chickpeas, as well as cereals and oilseeds. The initial phase of any protein concentrate manufacturing process involves preparing the raw material. For dairy, this starts with fresh skim milk. For plant-based concentrates, the process begins with defatted flour, meal, or flakes derived from seeds or legumes. These initial steps often include cleaning, de-hulling, and grinding to prepare the material for more intensive protein extraction.

Membrane Filtration for Dairy Protein Concentrates

Membrane filtration is the cornerstone of modern dairy protein concentrate (MPC) and whey protein concentrate (WPC) production. This physical separation process is valued for its gentleness, which helps preserve the protein's integrity and nutritional value. The primary technique used is ultrafiltration (UF), sometimes combined with diafiltration (DF).

The Whey Protein Concentrate (WPC) Process

Pasteurization and Separation: Fresh milk is first pasteurized to eliminate harmful bacteria. Enzymes or acids are then added to coagulate the casein, producing solid curds for cheese and leaving behind the liquid whey.
Ultrafiltration (UF): The liquid whey is passed through semipermeable membranes with specific pore sizes. Water, lactose, and minerals (smaller molecules) pass through as "permeate," while the larger whey protein molecules are retained as "retentate".
Diafiltration (DF): For higher protein concentrations (e.g., WPC80), water is added to the retentate during the ultrafiltration process. This washes away additional lactose and minerals, further purifying the protein.
Evaporation and Drying: The final, concentrated protein liquid is often evaporated to remove more water and then spray-dried into a fine powder. This powder is then cooled and packaged.

Wet Extraction and Isoelectric Precipitation for Plant Proteins

Wet extraction is a common method for producing plant-based protein concentrates, particularly from oilseeds like soy and legumes. This process relies on adjusting the pH to manipulate protein solubility.

The Soy Protein Concentrate (SPC) Process

Defatting: Whole soybeans are first defatted using a solvent, typically hexane, to create flakes or meal.
Alkaline Extraction: The defatted flakes are mixed with an alkaline solution (e.g., sodium hydroxide) to solubilize the proteins. This process leaves behind insoluble carbohydrates and fiber.
Separation: The protein-rich liquid is separated from the solid residue via centrifugation.
Isoelectric Precipitation: The pH of the liquid extract is adjusted using acid to reach the protein's isoelectric point (pI)—the pH at which the protein has a net-zero charge and minimum solubility. This causes the protein to precipitate out of the solution and form a solid curd.
Washing and Drying: The protein curd is collected, washed to remove residual salts, and dried, often via spray-drying or freeze-drying, to produce the final concentrated powder.

Dry Fractionation for Plant Proteins

As a more sustainable and less resource-intensive alternative to wet extraction, dry fractionation involves a purely physical separation process. It is particularly suitable for pulses like peas and chickpeas.

The Pea Protein Concentrate Process

Milling and Grinding: The raw peas are milled into a fine flour.
Air Classification: The flour is sent into a classifier chamber where air is used to separate particles based on size and density. Since protein particles are typically lighter and finer than starch particles, they are carried away in the air stream.
Collection: The lighter, protein-rich fraction is collected as the concentrate, while the heavier, starch-rich fraction is also recovered. This method results in a protein concentrate that retains most of the original fiber and other compounds.

Comparison of Manufacturing Methods


Feature	Membrane Filtration (Dairy)	Wet Extraction (Plant)	Dry Fractionation (Plant)
Principle	Physical separation based on molecule size.	Chemical manipulation of pH to change protein solubility.	Physical separation based on particle size and density.
Inputs	Skim milk or liquid whey.	Defatted plant meal (e.g., soy flakes).	Milled, whole legume or grain flour (e.g., pea flour).
Protein Yield	High purity (up to WPC80/MPC85).	High purity (often >70% protein).	Moderate purity (typically <65% protein).
Purity	Excellent, removes lactose and ash.	High, removes soluble sugars and anti-nutritional factors.	Lower, retains more fiber and anti-nutritional factors.
Resource Use	High energy for filtration and drying.	High water, energy, and chemical use.	Low energy and water, no chemicals.
Sustainability	Fewer byproducts than wet methods.	Produces significant effluent waste.	Environmentally friendly, no effluent.

Quality Control and Final Steps

Regardless of the extraction method, the final stages of manufacturing are critical for ensuring the safety, quality, and functionality of the end product. Quality control measures include testing for protein content, moisture, ash, and potential contaminants. The dried protein powders are then blended with other ingredients, such as flavors, before being packaged in airtight containers to prevent degradation. Adherence to strict quality standards is paramount, especially for products intended for human consumption.

The Evolution of Protein Concentration

The methods for concentrating protein have evolved significantly, moving from cruder precipitation techniques to sophisticated, high-tech processes. The rise of membrane technology, particularly ultrafiltration and diafiltration, has been a game-changer for the dairy industry, allowing for the creation of high-purity, low-lactose whey and milk protein products. Meanwhile, increasing demand for plant-based proteins has spurred the refinement of both wet extraction and the development of cleaner, more sustainable dry fractionation techniques. Novel methods like enzyme-assisted extraction and high-pressure processing are also being explored to improve yield and functional properties. The industry is constantly innovating to meet consumer demands for higher quality, more sustainable, and versatile protein ingredients.

Conclusion

The process of protein concentrate manufacturing is a dynamic and evolving field, with methods tailored to specific source materials and desired product outcomes. From the gentle, physical separation of ultrafiltration for dairy proteins to the pH-driven chemical extraction or resource-efficient dry fractionation for plant-based proteins, each technique follows a logical sequence of steps. The overarching goal is to efficiently remove non-protein components to produce a concentrated, high-protein powder suitable for a wide range of food and nutritional applications. Continued research and technological advancements promise to further enhance the efficiency and quality of these processes, delivering higher-quality protein ingredients to a growing global market.

Explore the manufacturing process for milk protein concentrates in further detail on the Idaho Milk Products blog.

Frequently Asked Questions

A protein concentrate has undergone a process to increase its protein content, typically reaching 65-80% protein by dry weight, and retains some fats and carbohydrates. An isolate undergoes further processing, like diafiltration, to remove more non-protein components, resulting in a purer product with over 90% protein.

During membrane filtration, liquid whey is pushed against a membrane with microscopic pores. The pores are large enough for smaller molecules like water and lactose to pass through but small enough to trap the larger protein molecules, effectively concentrating the protein in the remaining liquid.

No, the manufacturing processes are quite different. Animal-based proteins, especially dairy, rely heavily on membrane filtration, while plant-based proteins often utilize wet chemical extraction based on pH or dry physical separation methods like air classification.

The isoelectric point is the specific pH level at which a protein has no net electrical charge. By adjusting the pH of a protein-rich solution to this point, manufacturers cause the protein to clump together and precipitate out of the liquid, making it easier to collect.

Dry fractionation is more environmentally friendly than wet extraction because it uses significantly less water and no chemical solvents. It is also more energy-efficient and avoids generating large volumes of wastewater.

After the liquid or curd concentrate is produced through filtration or precipitation, it is subjected to a drying process. The most common method is spray-drying, which atomizes the liquid into a fine mist in a hot chamber, rapidly evaporating the moisture and leaving a fine powder.

The quality is affected by the source material, the specific processing methods (including temperatures and chemicals used), and the efficiency of the separation and drying stages. These factors determine the final product's protein content, solubility, flavor, and functional characteristics.