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The CORRECT option is (c) Colostrum

The EXPLANATION: Colostrum is a FORM of milk produced by the mammary glands of cows during pregnancy. Most species will generate colostrum just PRIOR to giving BIRTH.

Right option is (a) HOLSTEIN

Explanation: Holstein Friesians are a breed of dairy CATTLE ORIGINATING from the Dutch provinces of North Holland and Friesland, and Schleswig-Holstein in Northern GERMANY and Jutland. They are KNOWN as the world’s highest-production dairy animals.

The correct answer is (c) BALANCE TANK

For explanation I would say: The balance tank keeps the product at a constant LEVEL above the pump inlet. In other words, the head on the suction SIDE is KEPT constant.

The correct option is (a) To mix

The best explanation: An AGITATOR is a device or MECHANISM USED to PUT something into motion by shaking or stirring. There are SEVERAL types of agitation machines, including washing machine agitators and magnetic agitator. Agitators can come in many sizes and varieties, depending on the application.

The correct option is (b) Mixing tank

Easiest explanation: Mixing tank, as the name implies, these tanks are USED for mixing different products and for the ADMIXTURE of ingredients to the product. The tanks may be of the insulated type or have a SINGLE STAINLESS steel shell.

The correct option is (a) True

Best explanation: Storage TANK, if filling is INTERRUPTED, the PROCESSED milk is BUFFERED in the tank until the operation can be resumed. Similarly, milk from this tank can be used during a temporary processing stoppage.

The correct choice is (B) Intermediate STORAGE tank

The explanation: Intermediate storage tanks are USED to store a PRODUCT for a short time before it continues along the line. These tanks are used for buffer storage, to level out variations in flow. After heat treatment and cooling, the milk is pumped to a buffer tank, and from there to filling.

Correct option is (a) True

Best explanation: Storage SHELL has a double shell with a minimum of 70 mm mineral-wool insulation in between. The OUTER shell can be of stainless steel, but for economic REASONS it is usually made of mild steel and COATED with anti-corrosion PAINT.

Right answer is (c) STAINLESS steel

The best I can explain: They vary in size from 25 000 to about 150 000 litres and the WETTED surfaces are of stainless steel. They are often placed OUTDOORS to save on building costs. In these cases, the tanks are INSULATED.

The correct choice is (a) STORAGE tank

To explain I WOULD say: Silo tanks for milk RECEPTION belong to the storage category and have been described under “COLLECTION and reception of milk”.

Correct choice is (a) 150000 litres

The BEST explanation: The SIZES range from 150000 litres for the SILO tanks in the MAXIMUM category down to APPROXIMATELY 100 litres for the smallest tanks.

Right answer is (a) 150000 LITRES

Best explanation: Tanks in a DAIRY are used for a number of purposes. The SIZES range from 150000 litres for the silo tanks in the reception department down.

The correct choice is (d) Filling machine

The BEST I can explain: VALVES for constant INLET pressure are often used after separators and pasteurizers. Those for constant OUTLET pressure are used before filling machines.

Correct choice is (a) True

Easiest explanation: Pipes must be firmly supported. On the other HAND the pipes should not be so restrained that movement is prevented. The pipes will expand considerably when the product TEMPERATURES are HIGH and during cleaning. The resulting increase in length and TENSIONAL forces in bends and EQUIPMENT must be absorbed.

Correct ANSWER is (a) Pressure relief VALVE

To ELABORATE: A pressure relief valve MAINTAINS the pressure in the system. If the pressure is low, the spring holds the plug against the seat. When the pressure has reached a certain value, the FORCE on the plug overcomes the spring force and the valve opens.

The correct option is (c) Seat valve and butterfly valve

For explanation: There are many places in a piping SYSTEM where it must be possible to stop the flow or divert it to another line. These FUNCTIONS are PERFORMED by valves. Seat valves, manually or pneumatically controlled, or butterfly valves, are USED for this purpose.

The correct ANSWER is (c) K (v^2/2 g)

To explain: K (v^2/2 g) calculates head loss for Newtonian fluid. When fluid flows inside a pipeline, friction OCCURS between the moving fluid and the stationary pipe wall. The friction CONVERTS some of the fluid’s hydraulic energy into thermal energy. The thermal energy cannot be converted back to hydraulic energy, so the fluid experiences a drop in pressure. This CONVERSION and loss of energy is known as head loss.

Correct answer is (c) Sampling device

The best I can EXPLAIN: Some examples of fittings for PERMANENT welding are Tees, reducers and bends. This union allows disconnection without disturbing other pipe work. This type of joint is hence used to CONNECT PROCESS equipment, instruments, etc. that need to be removed for cleaning, repair or replacement.

Right option is (c) SAMPLING device

Best EXPLANATION: Sampling devices need to be installed at strategic POINTS in the plant to collect product samples for analysis. For quality control, such as determining the FAT content of milk and the pH value of CULTURED products, the samples can be collected from a sampling cock.

The correct ANSWER is (b) AISI 316

Easy explanation: For HYGIENIC reasons, all product-wetted parts of dairy equipment are MADE of stainless steel. Two main grades are used, AISI 304 and AISI 316. The latter grade is often called ACID proof steel.

Correct choice is (B) Copper

To ELABORATE: Plastic is USED for water and air lines. Plastic also provides TRANSPARENCY.

The CORRECT CHOICE is (a) Stainless steel

To explain I would say: All COMPONENTS in contact with the product are made of stainless steel. Stainless steel is easy to CLEAN and non corrosive.

Correct choice is (c) GENTLE treatment with high viscosity

Best explanation: This type of pump has 100% volumetric efficiency (no slip) when the viscosity exceeds approximately 300 CP. Because of the SANITARY design and the gentle treatment of the product, this type of pump is widely used for pumping cream with a high fat content, CULTURED milk products, curd/whey mixtures, etc.

Right answer is (b) Heavily AERATED liquids

Best explanation: Liquid-ring PUMPS for the dairy industry are USED where the product contains large quantities of air or gas, and where CENTRIFUGAL pumps therefore cannot be used. The clearances between impeller and CASING are small, and this type of pump is therefore not suitable for handling abrasive products.

Right answer is (a) Centrifugal pump

To explain I would say: Typical DAIRY pumps are the centrifugal, liquid-ring and positive displacement pumps. The three TYPES have different applications. The centrifugal pump is the type most widely USED in dairies.

The correct option is (c) Priming

The explanation is: Most pumps are not self-priming. In other words, the pump CASING MUST be filled with liquid before the pump is started, or the pump will not be able to function. In case the pump casing GETS filled with vapors or GASES, the pump impeller becomes gas-bound and incapable of pumping.

Correct CHOICE is (a) Reciprocating pump

The best explanation: Reciprocating pumps are GENERALLY designed to pump in LOW flow, high head applications. One of the most extreme of these applications is water JET cutting, where only a few gallons pass through the pump per minute, but exceed PRESSURES of 10,000 PSI.

Right answer is (b) Lower than

The BEST explanation: The CAPACITY of a pump has two COMPONENTS, the pump discharge rate and the discharge pressure. The discharge rate is normally measured in gallons per minute (gpm) in English units or LITERS per second (lps) in METRIC units. Discharge capacity of the reciprocating pump is less that of the centrifugal pump.

The correct CHOICE is (c) Centrifugal

Easiest explanation: Centrifugal pump is COMMONLY known as velocity pump.A centrifugal pump imparts velocity to a LIQUID. This velocity ENERGY is then TRANSFORMED largely into pressure energy as the liquid leaves the pump.

Right choice is (d) Centrifugal pump

Easiest EXPLANATION: Rotary-type positive displacement: internal GEAR, screw, shuttle block, flexible vane or sliding vane, circumferential PISTON, and flexible impeller, helical twisted or liquid-ring PUMPS.

Correct option is (a) Oils

To explain: Positive DISPLACEMENT rotary pumps rely on FINE CLEARANCES between moving parts for their efficient operation. When used for lubricating oil and hydraulic systems, rotary displacement pumps benefit from the sealing effect and PROVISION of lubrication between parts.

Correct option is (C) Centrifugal pump

Explanation: Centrifugal pump is not a positive displacement pump. Reciprocating pumps move liquid by means of a constant back-and-forth motion of a PISTON, plunger, or diaphragm within a fixed volume or cylinder. Reciprocating pumps can handle viscous and abrasive fluids. They are low-speed machines when compared with centrifugal and ROTARY.

Right choice is (a) Axial FLOW

Easy explanation: An axial flow PUMP is a type of centrifugal pump that uses an IMPELLER with vanes that direct the flow axially. Axial flow pumps create LESS pressure as compared to radial flow centrifugal pumps, but they can produce much higher flow RATES.

Correct CHOICE is (B) Temperature and atmospheric pressure

Explanation: The equilibrium that prevails between three STATES of aggregation is determined by temperature and atmospheric pressure. The rise in temperature during pasteurization for instance, dissolved AIR goes from solution to dispersion causing the problem.

Right CHOICE is (b) 1.29%

For explanation I would SAY: Commercial mixed raw milk constitutes about 1.29% of nitrogen in it. The TOTAL VOLUME of air in milk in the udder can be some 4.5 – 6 %, of which nitrogen constitutes about 1%.