{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,11,7]],"date-time":"2026-11-07T23:09:08Z","timestamp":1794092948782,"version":"4.8.0"},"reference-count":32,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2020,9,23]],"date-time":"2020-09-23T00:00:00Z","timestamp":1600819200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Foods"],"abstract":"<jats:p>In this study, novel spore pouches were developed using mashed potato as a food model inoculated with either Geobacillus stearothermophilus or Clostridium sporogenes spores. These spore pouches were used to evaluate the sterilization efficiency of Coaxially induced microwave pasteurization and sterilization (CiMPAS) as a case study. CiMPAS technology combines microwave energy (915 MHz) along with hot water immersion to sterilize food in polymeric packages. The spore pouches were placed at pre-determined specific locations, especially cold spots in each food tray before being processed using two regimes (R-121 and R-65), which consisted of 121 \u00b0C and 65 \u00b0C at 12 and 22 kW, respectively, followed by recovery and enumeration of the surviving spores. To identify cold spots or the location for inoculation, mashed potato was spiked with Maillard precursors and processed through CiMPAS, followed by measurement of lightness values (*L-values). Inactivation equivalent to of 1\u20132 Log CFU\/g and &gt;6 Log CFU\/g for Geobacillus stearothermophilus and Clostridium sporogenes spores, respectively was obtained on the cold spots using R-121, which comprised of a total processing time of 64.2 min. Whereas, inactivation of &lt;1 and 2\u20133 Log CFU\/g for G. stearothermophilus and C. sporogenes spores, respectively on the cold spots was obtained using R-65 (total processing time of 68.3 min), whereas inactivation of 1\u20133 Log CFU\/g of C. sporogenes spores was obtained on the sides of the tray. The results were reproducible across three processing replicates for each regime and inactivation at the specific locations were clearly distinguishable. The study indicated a strong potential to use spore pouches as a tool for validation studies of microwave-induced sterilization.<\/jats:p>","DOI":"10.3390\/foods9101342","type":"journal-article","created":{"date-parts":[[2020,9,24]],"date-time":"2020-09-24T02:56:43Z","timestamp":1600916203000},"page":"1342","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["Development of Bacterial Spore Pouches as a Tool to Evaluate the Sterilization Efficiency\u2014A Case Study with Microwave Sterilization Using Clostridium sporogenes and Geobacillus stearothermophilus"],"prefix":"10.3390","volume":"9","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8546-2858","authenticated-orcid":false,"given":"Aswathi","family":"Soni","sequence":"first","affiliation":[{"name":"Food Assurance, AgResearch, Palmerston North 4410, New Zealand"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7399-1114","authenticated-orcid":false,"given":"Jeremy","family":"Smith","sequence":"additional","affiliation":[{"name":"School of Food &amp; Advanced Technology, Massey University, Palmerston North 4410, New Zealand"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1562-3185","authenticated-orcid":false,"given":"Richard","family":"Archer","sequence":"additional","affiliation":[{"name":"School of Food &amp; Advanced Technology, Massey University, Palmerston North 4410, New Zealand"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Amanda","family":"Gardner","sequence":"additional","affiliation":[{"name":"Food Assurance, AgResearch, Palmerston North 4410, New Zealand"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kris","family":"Tong","sequence":"additional","affiliation":[{"name":"School of Food &amp; Advanced Technology, Massey University, Palmerston North 4410, New Zealand"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3980-4108","authenticated-orcid":false,"given":"Gale","family":"Brightwell","sequence":"additional","affiliation":[{"name":"Food Assurance, AgResearch, Palmerston North 4410, New Zealand"},{"name":"New Zealand Food Safety Science Research Centre,  Palmerston North 4410, New Zealand"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2020,9,23]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"433","DOI":"10.1016\/j.tifs.2020.01.030","article-title":"Microwave-induced thermal sterilization- A review on history, technical progress, advantages and challenges as compared to the conventional methods","volume":"97","author":"Soni","year":"2020","journal-title":"Trends Food Sci. 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