Steam economy of an evaporator is defined as the mass of water vaporized per unit mass of live steam supplied: $\text{Economy} = \frac{\text{Mass of water evaporated}}{\text{Mass of steam consumed}} = \frac{1500\text{ kg/h}}{2000\text{ kg/h}} = 0.75$. (For a single-effect evaporator, economy is typically $\lt 1.0$). Option analysis: (A) $0.75$ is the exact calculated evaporator economy. (B) $1.0$ is theoretical maximum for ideal single effect. (C) $1.33$ inverts steam and water. (D) $3.0$ is characteristic of triple-effect evaporators.

Food extrusion is a high-temperature short-time (HTST) bioreactor processing technique that integrates conveying, mixing, kneading, shearing, cooking/plasticizing, and shaping/texturing through a restricted die into a single continuous automated unit operation. Option analysis: (A) Extrusion combines all these mechanical and thermal unit operations. (B) Cold sterilization refers to radiation or filtration preservation. (C) Irradiation uses ionizing radiation for pathogen reduction. (D) Sous vide is vacuum pouch low-temperature cooking.