Shelf-life modeling of microwave-assisted thermal sterilized mashed potato in polymeric pouches of different gas barrier properties

This study investigated how the shelf-life of foods processed with microwave-assisted thermal sterilization (MATS) is affected by temperature and package gas barrier properties. We conducted accelerated shelf life testing of a mashed potato-based model food processed with MATS. The model food was processed to a lethality of F0 = 9.0 min, packaged in four pouch materials with different oxygen transmission rate (OTR) and water vapor transmission rate (WVTR), and then stored at 23 °C, 37 °C and 50 °C for up to 12, 6, and 2.8 months, respectively. Findings showed that there were significant temperature effects and the combined effects of OTR and WVTR on the food color (ΔE). Moisture loss and lipid oxidation were also affected by package over the storage periods. Shelf-life predictions were based on the model at different temperatures and OTRs (23 °C storage) using ΔE = 12 as the end point for acceptable quality, with Q10 values ranged from 2.85 to 3.15. The results provide valuable information for selecting packaging materials for MATS and other thermally processed foods.