Submitted to: Microwave Power Symposium Proceedings
Publication Type: Proceedings
Publication Acceptance Date: May 4, 2012
Publication Date: June 20, 2012
Citation: Trabelsi, S. 2012. Temperature Dependence of the Radio-Frequency Dielectric Properties of Chicken Meat. Microwave Power Symposium Proceedings. pp. 298-304. Interpretive Summary: Quality attributes of chicken meat are often assessed through measurement of a variety of physical properties including color, pH, water holding capacity (WHC), drip loss, cook yield and texture (Warner-Bratzler shear force value). Not only are these procedures tedious and time-consuming, but they are destructive and often involve costly instruments which require a skilled and well trained operator. It would be very helpful if rapid, nondestructive methods were developed to determine some of the meat quality attributes or their equivalent. Because chicken meat is composed on average of 70% water, 20% protein and 5% fat, dielectric measurement, which are particularly sensitive to water, may offer possible methods for sensing meat quality. The first step in developing such methods requires an understanding of the dielectric behavior of chicken meat, and it can be studied through dielectric spectroscopy. For this purpose, dielectric response of chicken breast meat was measured with an open-ended coaxial-line dielectric probe and network analyzer over a frequency range from 200 MHz to 20 GHz at temperatures ranging from -20 to 25 oC. Results are shown for samples of chicken breast meat presenting different quality attributes. Both the frequency dependence and temperature dependence are important in understanding the dielectric behavior of poultry meat and should ultimately lead to identifying correlations between the dielectric properties and quality attributes. Results of initial studies are presented in this paper. Frequency and temperature dependence of dielectric properties of chicken breast meat revealed the influence of ionic conduction and binding status of water molecules. Variations of dielectric constant plotted agains frequency show a slope change at about 4 GHz which indicates the possibile existence of two relaxations, with one taking place in the lower frequency range and totally masked by the effect of ionic conduction. However, the second relaxation is distinct and broad, and is centered at about 8 - 10 GHz, which is lower than that of liquid water (19 GHz at 25 oC). The temperature dependence shows a sharp increase at about 0 oC, which is typical of transition in the water phase from ice-like status to free water. Future development of techniques for rapid quality sensing through dielectric properties would benefit poultry meat producers processors, marketers, and consumers in maintaining high quality in meat products.
Technical Abstract: Dielectric properties of chicken breast meat were measured with an open-ended coaxial-line probe between 200 MHz and 20 GHz at temperature ranging from -20 oC to +25 oC. At a given frequency, the temperature dependence reveals a sharp increase of the dielectric constant and dielectric loss factor at about 0 oC which is typical of materials with high water content and indicates the water transition from tightly bound water (ice like) to loosely bound water (liquid like). Results are shown for samples of chicken breast meat of different quality attributes.