Refrigeration Engineering

• Lactulose Formation via Thermal Isomerization of Lactose:
• Lobry de Bruyn-Alberda van Ekenstein Transformation:
• Under intense heat treatment (e.g., in in-bottle sterilized or UHT milk), lactose (4-O-$\beta$-D-galactopyranosyl-D-glucose) isomerizes into Lactulose (4-O-$\beta$-D-galactopyranosyl-D-fructose).
• Physiological & Diagnostic Properties:
• Non-digestible disaccharide utilized clinically as an osmotic laxative and hepatic encephalopathy therapeutic, and serves as an official chemical index of severe milk heat treatment.
• Conclusion: Lactulose (Option 2).

Correct option: (2) Lactulose

• Extended Surface (Fin) Geometries in Heat Exchangers:
• Fins expand convective heat transfer surface area ($q = h A \Delta T$):
• (I) Longitudinal fins: Rectangular profiles attached along planar furnace or heat exchanger walls.
• (II) Radial (annular) fins: Concentric circular discs around cylindrical evaporator/condenser pipes.
• (III) Conical pin fins (spines): Protruding tapered rods maximizing heat dissipation with minimum fin weight.
• All three are standard, mathematically valid fin geometries.
• Conclusion: (I), (II) and (III) (Option 1).

Correct option: (1) 0), () and (I!)

Analyzing the statements in relation to Basics of thermodynamics and heat transfer:

The correct option is Option 1: Both Statement (I) and Statement (II) are true..