Studies on the Development and Modeling of Food Freeze-Drying Processes

• Published in: Japan Journal of Food Engineering Vol. 26; no. 1; pp. 1 - 9
• Main Author: NAKAGAWA, Kyuya
• Format: Journal Article
• Language: Japanese
• Published: Japan Society for Food Engineering 15.03.2025; 一般社団法人 日本食品工学会
• Subjects: collapse; freeze-drying; freezing; ice crystal; mathematical modeling
• ISSN: 1345-7942; 1884-5924
• DOI: 10.11301/jsfe.24658

The motivation for developing mathematical models for food production is to quantitatively derive various product qualities from the product components and processing conditions. This paper introduces the author’s studies on the modeling of the freeze-drying processes. The ice crystal formation is an important factor in determining the freeze-drying kinetics. Here, an approach to simulate the freezing process for estimating the ice crystal sizes was introduced, and the results was further applied to simulate the progress of freeze-drying. In freeze-drying of food, drying progresses three-dimensionally as the outer surface receives radiative heat, and the sublimation surface area changes as the progress of drying. The author proposed a model that simplifies these phenomena and verified the simulation results. An attempt to quantification of the occurrence of collapse, which could be related to the quality of freeze-dried products, was also introduced. The deformation under the changes in moisture content and viscosity due to drying was simulated, and the resulting deformation level was used as quantitative data. It is expected that these approaches will contribute to the development of methodologies that can easily and quantitatively handle the complex food qualities.