Step 1: Understanding the Concept:
Surimi is a refined fish protein paste produced by washing minced fish flesh to remove water-soluble proteins, fats, and pigments, leaving behind concentrated structural proteins.
This paste is then mixed with cryoprotectants and frozen, and is used to make textured seafood products like imitation crab meat.
Step 2: Detailed Explanation:
Fish muscle proteins are classified into three major groups based on their solubility:
1. Sarcoplasmic proteins (A): Water-soluble proteins (such as enzymes, myoglobin) that make up about 20--30% of fish muscle.
These proteins are undesirable in surimi because they interfere with gel formation and cause discoloration.
During surimi processing, they are washed away during the washing steps.
2. Stroma proteins (primarily Collagen) (C): Insoluble connective tissue proteins that make up about 3--10% of fish muscle. They do not contribute to gelation.
3. Myofibrillar proteins (B): Salt-soluble structural proteins (primarily actin and myosin) that make up about 65--75% of fish muscle.
Myofibrillar proteins are the key functional ingredients in surimi.
When salt (sodium chloride) is added to the washed surimi paste, it solubilizes these myofibrillar proteins.
Upon subsequent heating, these solubilized proteins denature and cross-link to form a strong, elastic, three-dimensional gel network.
This gel-forming ability gives surimi its unique texture and structural properties.
Therefore, myofibrillar proteins are the most important proteins for making surimi.
Step 3: Final Answer:
Myofibrillar proteins are the essential fish proteins responsible for forming the gel structure in surimi, which corresponds to Option (B).