Myofibrillar Protein Solubility (Detailed)

Myofibrillar proteins are soluble in:

Correct Answer: Salt only

Myofibrillar proteins (Actin, Myosin, Tropomyosin, Troponins) are salt-soluble only — they require a high ionic strength (salt solution) for solubilization and are NOT soluble in plain water.

Three Meat Protein Groups and Solubility

• Myofibrillar proteins: Salt-soluble (e.g., Actin, Myosin, Tropomyosin) → 50–60% of muscle proteins
• Sarcoplasmic proteins: Water-soluble AND salt-soluble (e.g., Myoglobin, glycolytic enzymes) → 30–35% of muscle proteins
• Stromal proteins: Insoluble in both water and salt (e.g., Collagen, Reticulin, Elastin) → 10–15% of muscle proteins

In sausage making, addition of salt extracts myofibrillar proteins (especially myosin) which are critical for binding and emulsification in meat products.