Environmental Engineering Reference
In-Depth Information
Figure 8.3
Summary of interactions between plastic packaging and the
food or beverage contents.
Of these, the permeation of O
2
and humidity affect the shelf life, while
migration of additives and scalping of flavors from food affects the sensorial
quality and safety of the food.
8.2.1 Oxygen and Water Permeability
Ingress of oxygen into the package is responsible for slow oxidation of food
contents especially at elevated storage temperatures, with the development
of off-flavors such as rancidity in fat-containing food items. Moisture in a
package can cause slow hydrolytic degradation of food as well as permit
microbial growth in non-asceptic packages. Either of these can alter the
delicate sensorial qualities of the edible contents. Gas transport properties
of packaging therefore often dominate the shelf life of food items.
