This study investigated how the sheii-life of foods processed with microwave-assisted thermal steriii- zation (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 Fo g.0 min. packaged in four pouch materials with different oxygen trans- mission rate (OTR) and water vapor transmission rate (wwTR), and then stored at 23 ec, 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 (4E). 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 E 12 as the end point for acceptable quality, with Qu values ranged from 2.95 to 3.15. The results provide valuable information for sclecting packaging materials for MATS and other thermally processed foods. o 2016 Elsevier Ltd. All rights reserved.