Measurement of Moisture Content in Powdered Food Using Microwave Free-Space Transmission Technique

Abstract:

In this study, microwave free-space transmission technique was applied to measure the moisture content of powdered food (wheat flour, milk powder, and coffee powder). In frequency range from 1 to 15 GHz, the microwave attenuation and phase shift due to moisture content of food samples were measured and analyzed using vector network analyzer, double rigid horn antennas, and sample holder filled with moist food samples. To estimate the relationship between moisture density of powdered food and the attenuation and phase shift, correlation analysis was performed. The correlation coefficients at each food sample were greater than 0.91. The calibration equation for moisture content measurement having attenuation and phase shift as independent variables at 15 GHz was developed and evaluated. The coefficient of determination and root mean square for all food samples were 0.974 and 0.328 % respectively.

• Periodical: Key Engineering Materials (Volumes 321-323)
• Pages: 1196-1200
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.321-323.1196
• Online since: October 2006
• Authors: Ki Bok Kim, Seon Gun Park, Ji Yeon Kim, Jong Heon Kim, Chan Joo Lee, Man Soo Kim, Man Yong Choi
• Keywords: Microwave Free-Space Transmission, Moisture Content, Moisture Density, Powdered Food

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