Size, shape and density - Quiz

A bakery researcher wants to measure the volume of a loaf of bread. Which method is most appropriate?

• Liquid displacement with water

• Solid displacement with rapeseeds

• Micrometer measurement

Which parameter is most critical for designing a conveyor system for tomatoes?

• Aspect ratio

• Roundness and sphericity

• Bulk density

You need to separate wheat grains from small stones. Which physical property is most useful?

• Color

• Density and size

• Surface area

When designing a pump for fruit juice, which density value is required?

• Bulk density

• Solid density

• Liquid density

A powder shows rapid reconstitution in water. This is due to:

• Large particle size and low surface area

• Small particle size and high surface area

• Low porosity

During freezing, density of water decreases because:

• Volume expands when water becomes ice

• Mass decreases during phase change

• Surface area increases

Bread samples are tested with rapeseed displacement. A high value of apparent volume indicates:

• The bread has high porosity and open structure

• The bread is very dense

• The bread has low moisture content

When bulk density of coffee powder is low, packaging design must consider:

• Larger package volume required for same mass

• Increased shelf life

• Reduced moisture migration

Gas displacement is preferred over liquid displacement when:

• Sample absorbs or reacts with liquid

• Sample is highly regular in shape

• Sample has very low porosity

Helium is often used in gas displacement because:

• It penetrates small pores due to small molecular size

• It increases pressure quickly

• It reacts with proteins