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 F-0 = 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 degrees C, 37 degrees C and 50 degrees 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 (Delta E). 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 degrees C storage) using Delta E = 12 as the end point for acceptable quality, with Q(10) values ranged from 2.85 to 3.15. The results provide valuable information for selecting packaging materials for MATS and other thermally processed foods. (C) 2016 Elsevier Ltd. All rights reserved.