Can plastic food containers effectively block odors?

The barrier properties (including odor blocking) of plastic food containers depend on the density and molecular structure of the material. The following is an analysis of their barrier capabilities:

1. Basic Barrier Capabilities

Polypropylene (PP): PP has good gas barrier properties, which can slow down the emission of odors from food to some extent. Its moderate density and smooth surface make it suitable for short-term storage of food odors.

Polyethylene terephthalate (PET): PET has excellent barrier properties, especially against moisture and oxygen, which is the main reason it is widely used in beverage bottles. Due to its good barrier properties, PET containers can effectively prevent external odors from entering, but during long-term storage, internal odors may become less noticeable due to adsorption by the container's inner walls.

2. Specialized Barrier Materials

For applications requiring extremely strong odor barrier properties (such as vacuum packaging for food or cured meat), ordinary PP or PET containers may be insufficient.

Barrier films (such as PVDC, EVOH): In the professional packaging field, barrier films containing PVDC (polyvinylidene chloride) or EVOH (ethylene-alcohol copolymer) are commonly used. These materials offer significantly better barrier performance than ordinary plastics, effectively reducing odor diffusion and migration.