Dielectric properties of silver carp(Hypophthalmichthys molitrix) surimi-soybean compound at 915 MHz and 2 450 MHz as affected by temperature and soy protein isolate

The dielectric constant and loss factor of silver carp(Hypophthalmichthys molitrix)surimi paste and surimi-soybean compound added by different proportions of soy protein isolate emulsion were measured by the open-ended coaxial probe method at 915 MHz and 2 450 MHz from 10 ℃ to 80 ℃.The results suggested that dielectric constant of silver carp surimi paste and surimi-soybean compound decreased with increasing temperature,however,loss factor increased.The dielectric constant and loss factor of silver carp surimi paste and surimi-soybean compound decreased with increasing frequency.With the addition of soy protein isolate emulsion ranging from 6.5% to 28%,the dielectric constant and loss factor increased.Penetration depth of silver carp surimi paste and surimi-soybean compound decreased both with increasing temperature,and with the soy protein isolates emulsion addition.Frequency,temperature,and soy protein isolate emulsion had a significant effect on the dielectric properties and penetration depth of silver carp surimi paste.The application of SPSS software to regression analysis and prediction of dielectric constant,loss factor and penetration depth was effective.