High-pressure processing effects on the barrier properties of flexible packaging materials

The aim of this research was to evaluate the influence of high-pressure processing on the barrier properties of flexible packaging. LDPE/PA/LDPE, LDPE/EVOH/LDPE, PET/LDPE/PA/EVOH/PA/LDPE, PET/Al/PA/PP, and PETprinting/PETmet/LDPE(coex)packaging were filled with distilled water, processed by three conditions (600 MPa/25 degrees C/10 min, 600 MPa/90 degrees C/10 min, and 0.1 MPa/90 degrees C/10 min) and evaluated when the barrier to water vapor, oxygen, and light. The different processing conditions had little effect on the water vapor barrier and did not affect the light barrier of the packaging. The biggest changes were in the oxygen barrier, increasing oxygen permeation by 1.15, 2.24, 1.65, and 13.10 times for packaging of LDPE/PA/LDPE, LDPE/EVOH/LDPE, PET/LDPE/PA/EVOH/PA/LDPE, and PETprinting/PETmet/LDPEcoex, respectively, after processing 600 MPa/90 degrees C/10 min, these results were influenced by the synergistic effect of high-pressure and high-temperature, indicating that, depending on the process condition and the composition of the packaging materials, the barrier properties may decrease and, as a consequence, cause a reduction in the shelf life of the food. Practical applications The global high-pressure processed food market is growing. In addition to knowing the effects of this technology on food, it is essential to evaluate packaging materials, since, in most cases, foods are processed and marketed in the same packaging. Studies that address the impact of different processing conditions on the barrier properties of different packaging materials are essential for the best use of this technology, as they can undergo changes that can lead to a reduction in the shelf life of food, which will also depend chemical composition of food and storage conditions (time, temperature, and relative humidity).