ICAR AIEEA PG Agriculture Engineering 14 July 2023 (Shift 1) Paper

Assertion (A) is true: loose housing systems result in excellent sanitary quality of milk because cows are brought into a dedicated, clean, easily sanitized separate milking parlour for milking rather than being milked in bedding areas. Reason (R) is false: cows are NOT milked in the loose loafing/resting barn; they are moved to a separate specialized milking parlour, which prevents milk contamination from manure and bedding. Option analysis: (A) (R) is false. (B) (R) is false. (C) (A) is true but (R) is false is the correct answer. (D) (A) is true.

In an existing air screen cleaner machine, screen dimensions (width and length) are fixed physical structural parameters that cannot be adjusted during operation. Operational cleaning efficiency is adjusted dynamically by regulating the feed rate (C) and controlling the feeding mechanism (D) (fluted roll/vibratory feeder) along with screen slope, oscillation frequency, and air velocity. Option analysis: (A) Screen dimensions are fixed geometric design features. (B) (C) and (D) only are operational adjustment parameters. (C) Dimensions are fixed. (D) Omits width.

The LSU dryer is a continuous-flow, baffle-type (mixing type) column dryer specifically designed for cereal grains, particularly paddy (C) and pulses (A). It provides uniform drying without over-heating grain kernels, preventing head rice breakage. It is not suitable for perishables like marine products or fruits/vegetables. Option analysis: (A) Marine products cannot be dried in column baffle dryers. (B) Fruits/vegetables require tray/tunnel dryers. (C) (A) and (C) only (pulses and paddy) are suitable granular crops. (D) Marine products are unsuitable.

Correct matching pairs: (A) Fouling occurs on heat transfer surfaces in heat exchangers (II) due to thermal deposition of milk proteins, minerals, or scale. (B) Raoult's law governs vapor pressure lowering in ideal solutions (III). (C) Plank's equation predicts freezing time (IV) of foods. (D) Airy's theory describes grain pressure distribution in deep storage bins and silos (I). Option analysis: (A) (A)-(II), (B)-(III), (C)-(IV), (D)-(I) is the exact match. (B) Swaps storage and freezing. (C) Swaps fouling and ideal solution. (D) Incorrect matches.

Corn germ contains high oil/fat content ($\approx 35\%$ oil) which undergoes rapid oxidative rancidity if left in flour. The T-D (tempering-degerming) dry milling process moistens (tempers) the kernel and uses a degermer (Beall degermer) to cleanly detach and separate germ and fibrous hull from the endosperm. Removing this oil-rich germ prevents rancidity, giving the resulting corn meal/flour substantially longer shelf-life. Thus, (A) and (R) are true and (R) is the correct explanation of (A). Option analysis: (A) Both are true and (R) explains (A). (B) (R) directly explains the mechanism behind (A). (C) (R) is true. (D) (A) is true.