Thermal Processing

Traditionally, thermal technologies are mainly used in food industry to reduce pathogenic microorganisms in food products. Our lab is evaluating the synergistic microbial inactivation potential of thermal treatments with selected antimicrobial compounds in low water activity foods. Also, we are interested in understanding the influence of water properties (e.g., water activity, water mobility, water content etc.) and solid properties (e.g., glass transitions) on inactivation of microorganisms in low water activity foods.

Research Directions:

  • Understanding the influence of water properties on microbial resistance and quality of foods during thermal treatments in low water activity environments
  • Water activity, water mobility and glass transitions

Students and Postdocs:

Amritha Jaya Prasad and Harleen Kaur Dhaliwal


Dr. Lynn McMullen (Department of AFNS)
Dr. Michael Gänzle (Department of AFNS)

Current Projects:

  • Understanding the influence of Water Properties on microbial inactivation during processing of low water activity foods
  • Thermal and antimicrobial treatments to improve low water activity food safety
  • Influence of water activity on thermal resistance of pathogens in low water activity foods
  • Mechanism of survival of enteric pathogens in low water activity environments.
  • *Gautam, B., Gänzle, M., **Roopesh, M. S.Influence of water activity on the thermal inactivation of Salmonella enterica in low-moisture foods (In Preparation).
  • *Tadapaneni, R. K., **Syamaladevi, R. M., Villa-Rojas, R., Tang, J. (2017). Design of a novel Thermal-Water Activity Cell (TAC) to study the influence of water activity on the thermal resistance of Salmonella in low-moisture foods. Journal of Food Engineering, 208, 48-56.
  • **Syamaladevi, R. M., Tang, J., Villa-Rojas, R., Sablani, S. S., Carter, B., Campbell, G. (2016). Influence of Water Activity on Thermal Resistance of Microorganisms in Low-Moisture Foods: A Review. Comprehensive Reviews in Food Science and Food Safety, 15(3), 353-370.
  • **Syamaladevi, R. M., Tang, J., Zhong, Q. (2016). Water Diffusion from a Bacterial Cell in Low-Moisture Foods. Journal of Food Science: Concise Reviews and Hypotheses in Food Science, 81(9), R2129-R2134.
  • Syamaladevi, R. M., *Tadapaneni, R. K., Xu, J., Villa-Rojas, R., Tang, J., Carter, B., Sablani, S. S., Marks, B. (2016). Water activity change at elevated temperatures and thermal resistance of Salmonella in all purpose wheat flour and peanut butter, Food Research International, 81, 163-170.
Project Sponsors:
NSERC Discovery, Alberta Livestock and Meat Agency (ALMA), Alberta Agriculture and Forestry