Food Processing Unit Operations Multiple Choice Questions on “Mechanical Separation – Sedimentation Theory”.
1. Where is sedimentation used?
a) Water treatment
b) Oil production
c) Essential oil production
d) Salt production
Answer: a
Clarification: Sedimentation is the physical water treatment process using gravity to remove suspended solids and other impurities from the water.
2. What are benefits of sedimentation?
a) Effective in removing fine particles
b) Effective in removing viruses
c) Effective in removing bacteria
d) Effective in removing yeast
Answer: a
Clarification: Sedimentation is the process where by using coagulant the time required to settle out suspended solids is reduced and is very effective in removing fine particles.
3. What is sedimentation principle?
a) Centrifugal acceleration
b) Gravity
c) Electromagnetism
d) Gravity, centrifugal acceleration and electromagnetism
Answer: d
Clarification: Sedimentation is the affinity for components in suspension to settle down against a barrier. This is due to forces acting on them. These forces are gravity, centrifugal acceleration and electromagnetism.
4. Where does sedimentation value used?
a) Bread
b) Chocolate
c) Salt
d) Sugar
Answer: a
Clarification: The sedimentation value is the degree of sedimentation of flour suspended in a lactic acid solution through a standard time interval and it is a measure of the baking quality.
5. What are the factors affecting sedimentation?
a) Concentration, particle size
b) Temperature, particle size
c) Pressure, concentration
d) Pressure, particle size
Answer: a
Clarification: Factors affecting sedimentation rate are particle size, density and concentration, and fluid viscosity, convection currents in the surrounding fluid, particle shape and orientation, and chemical pretreatment of the feed suspension.
6. Are these statements about the sedimentation velocity true?
Statement 1: It is an analytical ultracentrifugation method.
Statement 2: It is used for determining the molecular mass.
a) True, False
b) True, True
c) False, True
d) False, False
Answer: b
Clarification: Sedimentation velocity is an analytical ultracentrifugation process which measures the rate of molecules movement in response to centrifugal force produced in a centrifuge. It provides information about both the shape of molecules and molecular mass.
7. Which law is related to sedimentation?
a) Gauss’s law
b) Stroke’s law
c) Dalton’s law
d) Newton’s law
Answer: b
Clarification: The sedimentation investigation is established on stokes law permitting to which the velocity at which the particles settles down depends on size, shape and weight of grain.
8. What is Zeleny test?
a) Quality of pulses
b) Quality of wheat
c) Quality of sugar
d) Quality of oil
Answer: b
Clarification: Zeleny sedimentation test is used for evaluating the quality of wheat for the baking strength of the flour. This method is applicable only to Triticum aestivum L. wheat.
9. Who invented sedimentation?
a) Newton
b) G.G. Stokes
c) Antonin Prandtl
d) Al-Kindi
Answer: b
Clarification: G.G. Stokes invented sedimentation. Newton discovered gravity. Antonin Prandtl invented centrifugation. Al-Kindi invented distillation.
10. Is soluble component be removed by using sedimentation?
a) True
b) False
Answer: b
Clarification: Sedimentation is the method of separating an insoluble substance from a liquid in which it is suspended by allowing it to settle to the bottom of the container normally by gravitational force.