Effect of Salt and Sucrose Content on the Dielectric Properties of Salted Duck Egg White Protein Relevant to Radio Frequency Drying

Abstract

The dielectric properties of salted duck egg dispersions were measured at the selected frequency range of 10 to 300 MHz by the open-ended coaxial probe method using a network analyzer. The effect of salt content (0–8%) and sucrose content (0–8%) on radio frequency drying (RFD) and the variation of the dielectric properties of the salted duck egg white samples were studied. These results showed that both dielectric constant and dielectric loss factor decreased with the increase of frequency, and the influence was more significant at the lower frequency ranges. At 27.14 MHz, the dielectric constant and dielectric loss factor were increased but the electric penetration depth was increased with the addition of salt and sucrose. The RFD drying rate was significant increased after the adding of salt and sucrose.

Keywords:

• Dielectric constant
• Dielectric loss factor
• Penetration depth
• Radio frequency drying
• Salted duck egg white protein

ACKNOWLEDGMENT

The authors are grateful to the Galore Food Co. Ltd., Zhongshang City, China, for technical support.