Dielectric properties of Agaricus bisporus slices relevant to drying with microwave energy

International Journal of Food Properties

Zhifang Yu¹  Ning Jiang¹  Chunquan Liu²  Dajing Li²  Zhongyuan Zhang²  Jiapeng Huang²  Chunju Liu²  Camel Lagnika²  Min Zhang³ 

[1] College of Food Science and Technology, Nanjing Agricultural University;Institute of Farm Product Processing, Jiangsu Academy of Agricultural Sciences;Jiangnan University;

关键词: agaricus bisporus;    dielectric properties;    dielectric constant;    dielectric loss factor;    drying;    moisture;    temperature;   

DOI  :  10.1080/10942912.2017.1373666

来源: DOAJ

【 摘 要 】

Dielectric properties of sliced Agaricus bisporus samples, with 0.16–0.89 [g/g, wet basis (w.b.)] moisture content, were determined using a network analyser and an open-ended coaxial-line probe, over a frequency range of 915 MHz to 2450 MHz and a temperature range of 25°C to 60°C. The results showed that the permittivity of A. bisporus was a function of frequency, moisture content, and temperature. The dielectric constant and loss factor were directly proportional to moisture content and temperature, respectively, and both decreased with increasing frequency. However, the influence of temperature on the dielectric constant showed a different trend, as this was affected by the moisture content of the sample. The dielectric loss factor initially increased and then decreased with the decrease in moisture content. Both inflection points appeared at the moisture content value of 0.69 (g/g, w.b.), which represents the “semi-bound water transfer” point. Third-degree polynomial models could be used to describe dielectric constant and loss factor values as functions of moisture content and temperature. The penetration depth decreased with increasing frequency and temperature; however, this first decreased with decreasing moisture content and then increased. Notably, the penetration depth was at a low ebb when the moisture content ranged from 0.69 to 0.52 (g/g, w.b.), indicating easier uneven drying. Low frequency (915 MHz) with large penetration depth represents a highly effective method for large-scale industrial dielectric microwave drying of A. bisporus slices from the angle of uniformity.

【 授权许可】

Unknown