Casein drying

Casein, the primary protein in milk, is a versatile ingredient widely used in food products (e.g., cheese, nutritional supplements), adhesives, coatings, and pharmaceuticals due to its emulsifying, film-forming, and nutritional properties. Common Drying Methods: Spray Drying

Casein, the primary protein in milk, is a versatile ingredient widely used in food products (e.g., cheese, nutritional supplements), adhesives, coatings, and pharmaceuticals due to its emulsifying, film-forming, and nutritional properties. The drying process is essential to convert liquid casein curds or solutions into a stable, shelf-stable powder, ensuring consistent quality and functionality across applications.

Importance of Drying
Freshly precipitated or extracted casein contains 50–70% moisture, which promotes microbial growth, enzymatic degradation, or undesirable texture changes. Drying reduces moisture content to <10%, extending shelf life, improving solubility, and enabling precise formulation in dry mixes. Proper drying also preserves casein’s native structure, ensuring its functional properties, such as water binding and emulsification, remain intact.

Common Drying Methods

Spray Drying: Casein solution or suspension is atomized and dried with hot air (typically 150–200°C at the inlet, 70–90°C at the outlet). This produces fine, free-flowing powder with high solubility, ideal for instant food products. Rapid drying minimizes heat exposure, reducing protein denaturation risks.

Key Parameters

Temperature Control: Excessive heat (>90°C during spray drying) can denature casein, reducing solubility and functional performance.

pH and Pretreatment: Acid or rennet coagulation methods affect casein’s isoelectric point and drying behavior. Neutralization or washing steps before drying influence final product purity.

Particle Size Management: Post-drying milling or sieving ensures consistent particle size for target applications (e.g., fine powders for infant formula vs. coarse granules for adhesives).

Storage Considerations
Dried casein is hygroscopic and prone to caking. It must be stored in airtight, moisture-resistant packaging under cool (<25°C), dry conditions. Antioxidants may be added to prevent lipid oxidation in casein containing residual milk fats.