Carbonated Drink Manufacturers Eye on Recycled Plastic rPet Bottles

On a hot summer day, nothing is better than enjoying an ice-cold soft drink. It is estimated the global carbonated beverages market is expected to grow at a compound annual growth rate (CAGR) of 5.1% from 2020 to 2027.

Traditionally, most carbonated soft drinks use PET bottles. In the wave of the sustainable packaging initiative, more brand owners are switching to recycled plastic bottle such as rPET. Coca-Cola® recently announced the transition to 100% recycled plastic in all on-the-go bottles in Great Britain following other European countries. Statistics show that it requires 75% less energy to make a plastic bottle from recycled plastic, which is the best way to a cleaner world with less plastic waste and less fossil fuel emissions.

Similar to most polymer packaging materials, the rPET material is permeable and needs to be evaluated for the barrier properties. For carbonated drinks, one important measure is the carbon dioxide transmission rate (CO2TR). With the CO2TR data, the shelf life of the carbonated drink can be estimated.

To learn more regarding the challenges and solutions of testing barrier properties of plastic bottles, click below or continue reading the Application section of this newsletter below.

Introduction to the New PERMATRAN-C 4/30 for CO2TR Testing

The new C 4/30 analyzer was designed for labs looking to perform fast and accurate carbon dioxide transmission rate testing for quality control (QC) or R&D applications. It includes many of the advanced features offered by our Next Generation MOCON Permeation Analyzers such as: short test cycles, easy-to-use software, and automated control features, while featuring our 2-cell cartridge testing system that precisely measures the carbon dioxide transmission rate (CO2TR) of barrier films and packages. The removable cartridge system allows interchangeable use with MOCON’s wide range of test cartridges expanding the testing range and applications of the instrument. The analyzer’s simplified operation allows both experienced technicians and new users to easily obtain accurate and repeatable CO2TR results on every measurement.

Unlike other permeability test methods that measure change in gas pressure, the C 4/30 specifically measures CO2 gas concentration using proprietary Infrared sensing technology to directly determine the carbon dioxide transmission rate. Not only is this method faster, but it is also more accurate and can be used on both flat film samples and 3-dimensional packages like bottles. A popular feature for R&D labs is the Auto-Test function which automatically sets and adjusts the test settings during a film test to obtain proper transmission rate results. It is particularly helpful for testing new or unknown film types.

The PERMATRAN-C 4/30 Carbon Dioxide Permeation Analyzer complies with ASTM standard F2476 and provides very accurate and repeatable test results within a wide detection range from 0.5 to 8000 cc/(m2*day).

Carbon Dioxide Transmission Rate Testing and Applications

Carbon Dioxide Transmission Rate (CO2TR) is an important aspect for packages in the food, beverage, and pharmaceutical industries. For applications from carbonated soft drink, to medical IV bags, the packaging barrier material’s CO2TR plays a major role in protecting the quality and safety of the product.

In the Medical industry, most IV bags or blood bags are made from PVC films which usually have high CO2TR value. During medical procedures such as dialysis for patients with lung or kidney diseases, CO2 is considered a toxin for the blood and is removed by external medical equipment. Blood bags are used to temporary store “dirty” blood from the vein during cleaning process. The higher the TR, the faster the CO2 permeates through the blood bag. When it comes to death and life, the transmission rate of the PVC film needs to be accurately understood. PERMATRAN-C 4/30 uses a unique IR Sensor that only responds the CO2 molecules, which guarantees the accuracy of the measurement.

In Carbonated drink industry, CO2TR testing is an important element of the R&D design process as well as QA/QC operations. With the PERMATRAN-C 4/30, which conforms to ASTM F2476, the testing and correlation estimate of the product shelf life can be more accurately and effectively verified than with traditional Zahm-Nagel test (ASTM F1115). A comparison study by Ametek Mocon showed a high correlation between the two methods however the ASTM F2467 method is much faster than the ASTM F1115. The IR sensor instrumental usually needs up to 6-7 days for the CO2TR test to reach equilibrium or complete a test, while the Zahm-Nagel pressure monitoring method will take months to complete. Additionally, the IR Sensor Method demonstrates much higher repeatability and accuracy over the Zahm-Nagel Method, which benefits both R&D innovation and QA/QC verification processes.

For more details about above applications, click below for related white paper and technical note articles.