As consumer preference for fresh food products grows, so does the need for transparent packaging. However, refrigeratable, moisture-containing food products are susceptible to fog formation when packaged, making it difficult to ensure package clarity and food freshness.
Gain insight into how anti-fog coatings help address this issue and the smart choice to make when considering coatings for your packaging needs.
How Anti-Fog Coatings Keep Packaging Clear and Food Fresh
Fresh foods are packaged in plastic, refrigeratable containers to prolong their shelf life and increase consumer convenience. However, during refrigeration, air and water vapor get trapped within the package. As the food product expels moisture, it causes water droplets to form on the inside of the package and the light to refract in many directions across its lid. This fog makes it difficult for people to see through the package to assess food freshness and makes food susceptible to faster decay.
When applied to the packaging lid, anti-fog coatings cause water vapor in the air as well as migrated moisture from the food to create a thin, uniform, transparent film instead of water droplets. By altering how the water droplets form, the packaging lid remains much more transparent with minimal light refraction and fog creation. This enables the packaging to be clear and extends food quality.
Why Certain Anti-Fog Coatings are the Smart Choice to Make
While all anti-fog coatings are designed to aid in clear packaging and food freshness, certain coatings offer advantages over other options.
Advantage #1: Enhanced Clarity
For example, when applied to a PET lid stock, PET-based anti-fog coatings are able to modify the chemical nature of the lid stock itself. This modification further aids in product visibility and enables converters to better meet consumer preferences for clear packaging. These coatings also can be sealed onto tray stocks, such as APET and RPET, for enhanced clarity.
Advantage #2: Improved Recyclability
Additionally, PET-based anti-fog coatings improve the recyclability of the final package. Many anti-fog coatings are PE or PP-based. When these coatings are applied to a PET or similar lid stock, the overall packaging is no longer able to be recycled into one single stream. Instead, the packaging tray and lid first must be separated due to incompatibility. With PET-based anti-fog coatings, and since they can be heat sealed to APET and RPET tray stocks, this is not the case, and they are able to aid in easy package recyclability.
Advantage #3: Increased Performance
Other packaging substrates may lack certain properties that can cause packaging clarity and food freshness issues even when anti-fog coatings are used. For example, PE and PP packaging substrates do not offer sufficient gas barrier properties. By letting more oxygen and other gases into the package than desirable, the packaging is less clear, and the food inside is likely to decompose more quickly.
However, when PET-based anti-fog coatings are used on PET lid stock, the following benefits apply:
> Excellent clarity
> High mechanical strength
> Good chemical resistance
> High barrier properties
> Stability over wide temperature range
Bostik’s smart PET-based anti-fog coatings are designed to improve operational efficiencies and overall package aesthetics while meeting consumer preferences for transparent packaging and extended food freshness.