Food Engineering Questions and Answers – Unit Operations – Mixing-2

This set of Food Engineering Multiple Choice Questions & Answers (MCQs) focuses on “Mixing-2”.

1. Which of the following is NOT an application of mixing solids in the food industry?
a) Biscuit/bakery making
b) Poultry and cattle feed
c) Chips and snacks industry
d) None of the mentioned
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2. Which of the following is NOT a mixing involved with fluids in the food industry?
a) Soup powders
b) Carbonated drinks
c) Oxygen transfer in fermentation broths
d) None of the mentioned
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3. Which of the following does NOT include power required for mixing by an impeller?
a) Rheological nature of the fluid
b) Friction in the motor
c) Speed, nature and type of the impeller
d) None of the mentioned
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4. Power required for a gassed system is more than that required for an ungassed system.
a) True
b) False
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5. Statement 1: Froude number relates the gravitational effect which is important when the liquid is agitated by an impeller.
Statement 2: When N_Re,i < 300, N_Fr is ineffective.
a) True, False
b) True, True
c) False, False
d) False, True
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6. With respect to the relationship between the power number and the impeller Reynolds’s number, which amongst the following statements is true?
a) In the turbulent region, the N_Re,i has no impact over N_Po
b) In the transient region, the N_Re,i has no impact over N_Po
c) In the laminar region, the N_Po continually falls as N_Re,i increases
d) None of the mentioned
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7. Statement 1: In the transient zone, the power input depends on the density and viscosity of the fluid.
Statement 2: In the laminar zone, the power input depends on the density only. It is independent of the viscosity of the fluid.
a) True, False
b) True, True
c) False, False
d) False, True
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8. Statement 1: For non-Newtonian fluids, another term called apparent viscosity is used as their viscosity changes with the change in the shear rate.
Statement 2: For non-Newtonian fluids, between the transition region, the power number for non-Newtonian fluids is slightly higher than that for Newtonian fluids.
a) True, False
b) True, True
c) False, False
d) False, True
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9. Statement 1: Where P_g is power for a gassed system and P_o is power for an ungassed system, P_g/P_o is _____
Statement 2: Na stands for _____
a) < 1, aeration number
b) > 1, aeration number
c) < 1, consistency index
d) > 1, consistency index
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10. Statement 1: Flat blade/curve blade/arrow head/vaned disc turbines are generally used for gas-liquid mixing.
Statement 2: Helical screw/ribbon mixer/gate anchor are generally used for solid-solid mixing.
a) True, False
b) True, True
c) False, False
d) False, True
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11. Which of the following is true with respect to Carbonation?
a) Gas-liquid mixing
b) Helps improve storage life
c) Increased pressure
d) All of the mentioned
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12. With respect to dipping oil emulsions, which of the following is true?
a) Used for easy dehydration of food
b) Gives a thin layer of coating on the fruit berries
c) Dipping oil made from an emulsion by mixing of fatty esters with some amount of aqueous potassium carbonate solutions by high speed impellers
d) All of the mentioned
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Sanfoundry Global Education & Learning Series – Food Engineering.

To practice all areas of Food Engineering, here is complete set of 1000+ Multiple Choice Questions and Answers.