Nature of Myofibrillar Proteins

Myofibrillar proteins are:

Correct Answer: Both Fibrous and Globular

Myofibrillar proteins include both fibrous and globular types.

Examples of Myofibrillar Proteins

• Myosin — fibrous protein; thick filament; ~60% of myofibrillar protein; major emulsifying protein in sausage making
• Actin — globular (G-actin) that polymerises to filamentous (F-actin); thin filament
• Tropomyosin — fibrous; regulatory protein on thin filament
• Troponin (T, C, I) — globular; Ca²⁺-binding regulatory complex
• Desmin, Connectin (Titin) — structural proteins of the Z-disc

Classification of Meat Proteins

• Myofibrillar — Salt-soluble; 50–60% of total; Both fibrous & globular
• Sarcoplasmic — Water-soluble; 30–35%; Globular (e.g., myoglobin, enzymes)
• Stromal — Insoluble; 10–15%; Fibrous (collagen, reticulin, elastin)