Food and Bioprocess Technology

, Volume 11, Issue 5, pp 979–990 | Cite as

Modelling of Thermal Sterilisation of High-Moisture Snack Foods: Feasibility Analysis and Optimization

  • Jing Ai
  • Torsten Witt
  • Michael J. Gidley
  • Mark S. Turner
  • Jason R. Stokes
  • Mauricio R. Bonilla
Original Paper


High-moisture snacks, such as steamed buns and rice cakes, are traditional and popular in Asian countries. However, their shelf life is short, primarily due to microbial spoilage. Current manufacturing methods address this shortcoming through the use of chemical preservatives. To satisfy consumers’ demand for preservative-free food, thermal sterilisation of a model high-moisture snack (steamed rice cakes) is investigated in this work. Bacillus cereus spores are heat-resistant pathogens typically found in rice products; hence, they constitute a suitable candidate to assess the effectiveness of thermal sterilisation. A validated combination of predicted temperature profile of rice cakes based on thermal properties extracted experimentally with thermal inactivation kinetics of B. cereus spores allows us to assess the sensitivity of processing conditions to sterilisation efficiency. Using both experimentation and modelling, it is shown that enhancement of heat transfer by improving convection from the heating medium (either water or steam) has a limited effect on inactivation due to the intrinsic kinetics of spore inactivation.


Heat transfer model Rice cakes Spore thermal inactivation Inactivation kinetics High-moisture snacks 



This study was supported by the ARC Industrial Transformation Training Centre ‘Agents of Change’ (IC130100011).


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Copyright information

© Springer Science+Business Media, LLC, part of Springer Nature 2018

Authors and Affiliations

  1. 1.Centre for Nutrition and Food Sciences, Queensland Alliance for Agriculture and Food InnovationUniversity of QueenslandBrisbaneAustralia
  2. 2.School of Agriculture and Food SciencesUniversity of QueenslandBrisbaneAustralia
  3. 3.School of Chemical EngineeringUniversity of QueenslandBrisbaneAustralia
  4. 4.Basque Centre for Applied Mathematics (BCAM)BilbaoSpain

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