Food Engineering Topic 7

What is the primary function of a mechanical refrigeration system?

• To increase the temperature of food

• To remove heat from a system

• To maintain ambient temperature

• To freeze food instantly

Which component of the refrigeration cycle is responsible for compressing the refrigerant gas?

• Compressor

• Expansion valve

• Evaporator

• Condenser

What does the term 'refrigeration load' refer to?

• The temperature of the refrigerant

• The rate of heat removal needed

• The amount of refrigerant used

• The size of the refrigeration unit

Which law of thermodynamics is relevant to the operation of refrigeration systems?

• Zeroth law

• First law

• Second law

• Third law

What is the purpose of the expansion valve in a refrigeration system?

• To absorb heat from the environment

• To condense the refrigerant

• To decrease the pressure of the refrigerant

• To increase the pressure of the refrigerant

Which refrigerant is known as Freon 12?

• Carbon dioxide

• Ammonia

• Monochlorodifluoromethane

• Dichlorodifluoromethane

What happens to the enthalpy of the refrigerant during the condensation process?

• It remains constant

• It fluctuates

• It decreases

• It increases

In a pressure-enthalpy diagram, what does the area enclosed by the bell-shaped curve represent?

• Subcooled liquid region

• Two-phase region

• Superheated vapor region

• Saturated liquid region

What is the effect of reducing storage temperature on food products?

• Increases microbial activity

• Decreases chemical reaction rates

• Increases freezing damage

• Decreases shelf life

What is the primary goal of controlled atmosphere storage?

• To increase oxygen levels

• To freeze food quickly

• To maintain high temperatures

• To reduce respiration rates