Abattoir & Poultry Processing Plants

• Purplish Red $\to$ (II) Deoxymyoglobin: Reduced myoglobin ($Fe^{2+}$, water bound at 6th coordinate position); characteristic color of freshly cut vacuum-packaged meat.
• Brown $\to$ (III) Metmyoglobin: Oxidized ferric myoglobin ($Fe^{3+}$, $OH^-$ bound); responsible for surface browning in aged or spoiled retail meat.
• Bright Red $\to$ (IV) Oxymyoglobin: Oxygenated myoglobin ($Fe^{2+} + O_2$); "bloomed" fresh meat exposed to atmospheric oxygen.
• Pink $\to$ (I) Nitrosyl Haemochromogen: Denatured globin complex formed when cured nitrosomyoglobin ($Fe^{2+}\text{-NO}$) is thermally cooked (gives cured ham and frankfurters their stable pink color).

Correct option: (4) (A) - (II), (B) - (III), (C) - (IV), (D) - (I)

• Assertion (A) is True: During the lag phase of bacterial growth, cells do not divide numerically, but they are metabolically hyperactive: synthesizing enzymes, RNA, and structural cofactors, leading to a substantial increase in individual cell size.
• Reason (R) is True: The fundamental principle of chilling/refrigeration ($0\text{ to }4^\circ\text{C}$) is to drastically slow down biochemical reaction rates, thereby prolonging the microbial lag phase so that exponential growth does not occur during storage.
• Relationship: Both statements are true, but (R) concerns food refrigeration preservation principles rather than explaining the cytological reasons for cell enlargement during the lag phase.

Correct option: (2) Both (A) and (R) are true but (R) is NOT the correct explanation of (A).

• Mechanisms of Electrical Stimulation (ES) Tenderization:
• Applying high- or low-voltage electrical current to freshly slaughtered carcasses tenderizes meat via three interrelated pathways:
• Prevention of Cold Shortening: Accelerates post-mortem glycolysis, reducing carcass pH to $\lt 6.0$ before chilling temperatures reach $\lt 10^\circ\text{C}$.
• Hastening of Rigor Mortis: Depletes ATP reserves rapidly, causing accelerated onset of rigor mortis within 1–2 hours.
• Physical Disruption of Muscle Fibers: Violent muscular contractions induce extensive structural tearing, micro-fractures, and fragmentation of myofibrillar proteins.
• Conclusion: (B), (C), and (D) only.

Correct option: (4) (B), (C) and (D) only.