Protein Concentrate Production Solutions

Protein concentrates are a major category of plant protein products, distinctly defined and processed differently from protein isolates. Their core characteristic is the selective removal of certain non-protein components (primarily soluble sugars, ash, etc.) through physical methods, thereby increasing the protein "concentration." While not pursuing extreme protein purity (≥90%) like isolates, they retain more of the raw material's natural properties and functional components, such as insoluble dietary fiber.

1.Raw Material Pretreatment Section

Defatted meal (soy, pea, etc.) is received, ground to an optimal particle size, and conditioned. This step prepares a uniform feedstock for efficient extraction

2.Alcohol-Wash Extraction Section

This is the heart of the process. The prepared meal enters a multi-stage counter-current extractor where it contacts a 60-70% aqueous ethanol solution. The solvent effectively dissolves soluble sugars (sucrose, raffinose, stachyose), off-flavor compounds, and some minerals while causing protein denaturation and reducing solubility. After multi-stage extraction, the solid phase is separated from the sugar-rich ethanol stream (molasses) using a screw press or centrifuge.

3.Desolventizing & Drying Section

The wet cake, containing residual ethanol, is fed into a desolventizer-toaster (DT). Indirect and direct steam strips the ethanol, which is recovered via condensers and purified in a distillation column for reuse—a critical system for economic efficiency and solvent recovery (>95%). The desolventized material is then dried in a fluidized bed dryer or tube bundle dryer and cooled.

Key Advantages

Cost-Effective Protein Enrichment

The alcohol-wash process efficiently removes soluble carbohydrates and anti-nutritional factors, boosting protein concentration to 65-70% (dry basis) while maintaining favorable production economics through high-efficiency solvent recovery.

Retained Nutritional & Functional Profile

Unlike isolates, protein concentrates preserve beneficial native components like insoluble dietary fiber, contributing to a nutrient-dense ingredient suitable for a wide range of food systems, from bakery to meat analogs.

Proven Industrial Scalability

Based on mature solvent extraction technology, the process is designed for continuous, large-scale operation with high automation, ensuring consistent product output and quality.

Flexible Feedstock Compatibility

The line can efficiently process various defatted plant meals, including soy, pea, and wheat, allowing for adaptable production based on raw material availability and market demand.

Main Equipment

Multi-Stage Counter-Current Extractor

The multi-stage counter-current extractor is the core unit for the selective removal of soluble sugars and impurities. In this system, prepared meal and aqueous ethanol solvent flow in opposite directions through several stages, maximizing contact and extraction efficiency. This design ensures thorough washing of solids while minimizing solvent usage. Constructed in food-grade stainless steel, it enables continuous, high-capacity operation essential for economical concentrate production.

Desolventizer-Toaster (DT)

The desolventizer-toaster (DT) is a critical unit for removing residual ethanol from the extracted wet cake. It typically employs a combination of indirect heating (via steam jackets or trays) and direct steam sparging (stripping) to evaporate the solvent. The system is designed to handle solvent-laden materials safely, with integrated vapor recovery lines feeding into the solvent condensation and distillation system. Proper operation ensures complete solvent removal, eliminates residual odors, and controls the final moisture and protein functionality of the product.

Grinding Mill / Pulverizer

The grinding mill (or pulverizer) is an essential unit for reducing the particle size of dried protein concentrate cake into a uniform, fine powder. Utilizing high-speed rotating hammers, impact blades, or air-jet milling technology, it efficiently breaks down dried agglomerates and controls final powder fineness (typically targeting 80–120 mesh). The mill is equipped with an integrated screening system to ensure consistent particle size distribution, which is critical for product solubility, dispersibility, and end-use application performance. Constructed in food-grade stainless steel, it supports hygienic, continuous operation and is vital for achieving the desired physical properties of the final protein concentrate powder.

Q.What are the key factors affecting the functionality of protein concentrate?
- A: The key factors are the extraction method (alcohol-wash vs. acid-wash vs. water-wash) and the subsequent thermal treatment during desolventizing and drying. Alcohol-wash typically results in denatured protein with low nitrogen solubility index (NSI), suitable for applications where water binding or gelation is not critical. Process control is essential to balance protein yield with target functional properties like water/oil holding capacity.
Q. Can other feedstocks besides soy be processed on this line?
- A:Yes. The core principles of the alcohol-wash extraction process are applicable to other defatted plant meals, such as pea or certain cereal meals. However, process parameters like solvent concentration, extraction time, and temperature may need optimization based on the specific composition and characteristics of the alternative feedstock.