Thermophysical properties of Cordyceps militaris change during the freezing process

• Published in: IOP conference series. Earth and environmental science 2023-12, Vol.1278 (1), p.12034
• Main Authors: Nguyen, Van – Phuc, Nguyen, Nguyen-An, Luong, Duc – Vu
• Format: Article
• Language: English
• Subjects: Ambient temperature; Cordyceps militaris; Density; energy; Enthalpy; Freeze drying; Freezing; Freezing point; freezing process; Heat; Heat transfer; Mass transfer; Mathematical analysis; Melting points; Parameters; Specific heat; Thermal conductivity; Thermal diffusion; Thermal diffusivity; Thermophysical properties
• ISSN: 1755-1307; 1755-1315
• DOI: 10.1088/1755-1315/1278/1/012034

This study focuses on determining the thermophysical parameters of Cordyceps militaris in the freezing stage of the freeze-drying process. When the temperature of Cordyceps militaris changed from an ambient temperature of 25°C to a freezing temperature of -45°C, the thermophysical parameters of Cordyceps militaris changed much. The study determined the initial freezing point temperature of Cordyceps militaris to be -0.6°C. At temperatures above the initial freezing point, the density (ρ) and specific heat (c) increase slightly as the temperature decreases. In contrast, thermal conductivity (k), thermal diffusivity (a), and enthalpy (h) decrease. However, at temperatures below the initial freezing point, when the temperature decreases, the density, specific heat, and enthalpy decrease while the coefficient of thermal conductivity and thermal diffusion increase. The results obtained from this study can be applied in calculating the heat and mass transfer during the freezing phase in the freeze-drying process of Cordyceps militaris .