Question

............. is a non-lysosomal proteolytic enzyme which helps in tenderization of meat.

• A. Calcium activated neutral proteises
• B. Capthepsin-B
• C. Acid phosphatase
• D. Capthepsin-D

Hint:

Calpains require calcium for activation, whereas their endogenous inhibitor, calpastatin, regulates this process.
Animals with higher levels of calpastatin (such as certain breeds of cattle) produce tougher meat because the calpastatin inhibits calpain-mediated post-mortem tenderization.

Answer 1

The Correct Option is A

Step 1: Understanding the Concept:
Post-mortem tenderization is a tural enzymatic process that occurs during the aging of meat.
This tenderization is driven by endogenous proteolytic enzymes that break down specific structural proteins in myofibrils.

Step 2: Detailed Explation:
The endogenous proteases responsible for post-mortem tenderization belong to two main cellular systems:
• Lysosomal enzymes (Cathepsins): These are acidic proteases located within lysosomes (e.g., Cathepsin B, D, H, L). They are active under acidic conditions, but they must be released from the lysosome to degrade myofibrillar proteins.

• Non-lysosomal enzymes (Calpains): These are intracellular, neutral cysteine proteases located in the cytosol. They require calcium ions for activation and are officially desigted as Calcium Activated Neutral Proteises (or Calpains).
The calpain system (particularly \(\mu\)-calpain and m-calpain) is widely recognized as the primary enzymatic system driving post-mortem tenderization.
Calpains degrade specific key structural proteins (such as titin, nebulin, and desmin), weakening the myofibrillar structure and tenderizing the meat.
Since they operate at neutral pH and are not located in lysosomes, they are the key non-lysosomal proteolytic enzymes involved.

Step 3: Fil Answer:
The correct option is (A).