STM3163 permeation

Which of the following is a characteristic of gas?

• Permeation is directly proportional to barrier

• Permeable to glass and metal packaging materials

• Exist only in gaseous state at ambient temperature and atmospheric pressure

• Condensable at ambient temperature

What is the major mechanism of transport of gas and vapor through a plastic film or package wall?

• Diffusion

• Adsorption

• Leak

• Permeation

What is the effect of oxygen ingress on dehydrated meat, egg, cheese, and fried food?

• Reduces nutrient value

• Leads to lipid oxidation and off flavors

• Causes sogginess

• Enhances flavor and color

Which packaging material is not permeable to gas and vapor?

• Plastic

• Glass

• Metal

• Paper

Which behavior is exhibited by the diffusion of permanent gases in polymers?

• Fickian behavior

• Concentration dependent behavior

• Concentration independent behavior

• Non-Fickian behavior

How total permeability of a multilayer film calculated?

• difference of the permeability of individual layers

• product of the permeability of individual layers

• average of the permeability of individual layers

• sum of the permeability of individual layers

Which polymer offers low oxygen barrier?

• PET

• PE

• PP

• EVOH

Which factor improves the gas and vapor barrier of polymers?

• 
  Increasing regularity of molecular structure

• Increasing temperature

• Increasing light exposure

• Increasing humidity

What causes CO2 to permeate faster than O2 through the polymer matrix?

• Lower diffusivity

• Higher diffusivity

• Lower solubility

• Higher solubility

the main reason to prevent both pinholes and channel leaks in food packaging?

• To increase gas barrier

• To decrease gas barrier

• To reduce cost

• To improve aesthetics