Livestock Products Technology- ICAR JRF/SRF 2024

• Statement (I) is Incorrect: BOD and COD are not the only methods; abattoir effluent polluting strength is comprehensively evaluated using Total Suspended Solids (TSS), Total Kjeldahl Nitrogen (TKN), oil and grease, phosphorus, and microbial coliform counts alongside BOD and COD.
• Statement (II) is Correct: Chemical Oxygen Demand (COD) chemically oxidizes both biodegradable and non-biodegradable organic compounds using boiling potassium dichromate in acid, completing the test within 2 to 3 hours (compared to 5 days for $BOD_5$), making COD a much faster and reliable indicator for sizing effluent treatment plants.

• Statement (I) is Incorrect: The classification is inverted. Oxidizing disinfectants include peracids (peracetic acid), hydrogen peroxide, chlorine, and iodophors. Non-oxidizing disinfectants include quaternary ammonium compounds (QACs / 'quats'), biguanides, and amphoterics.
• Statement (II) is Correct: Non-oxidizing agents (like QACs) act by disrupting cell membrane permeability, are heat-stable, non-corrosive to stainless steel equipment, and leave a persistent bacteriostatic residue on sanitized abattoir surfaces.

• Statement (I) is Incorrect: While $\alpha$-lactalbumin is not coagulated by rennet or dilute acids at ambient temperatures, it is definitely denatured and precipitated by heat at temperatures above $65\text{--}70^\circ\text{C}$.
• Statement (II) is Incorrect: $\alpha$-Lactalbumin is unique among whey proteins precisely because it possesses a high-affinity, tightly bound calcium-binding site (one $Ca^{2+}$ ion coordinated by aspartate residues) which is essential for stabilizing its native folded conformation against thermal denaturation and proteolysis.
• Conclusion: Both Statement (I) and Statement (II) are incorrect.

Correct option: (2) Both Statement (|) and Statement (II) are incorrect