Physico-Geometric Approach to the Processes of Thermal Decomposition of the Guinea Fowl (Numida meleagris) Eggshell’s Bionanocomposites

Abstract

Using the physico-geometric approach in the thermal programmed desorption mass spectrometry (TPD-MS method), the possibility of indirect estimation of the three-dimensional structure of a multilayer heterogeneous composite of “calcium carbonate (calcite) – protein” type of eggshells of a guinea fowl (Numida meleagris) eggs. The method is based on the difference in rates of thermal decomposition rates of calcium carbonate depending on the peculiarities 3-D micro-, nanostructure of each layer. Increased porosity and reduction in the density of crystallite packing in local areas of the shell is accompanied by a shift of maximum peaks in the complex curves of the dependence of carbon dioxide release during process of thermal destruction (thermograms) in the direction of low temperatures. The TPD-MS makes it possible to determine of quality level and mechanical properties of the eggshells in cases where traditional methods of microscopy don’t give reliable results. Thus, this study shows the presence of reliable structural differences in different areas of the nanocomposite layers of the eggshell of guinea fowl (Numida meleagris), distinguished by increased strength. These experimental and theoretical results can be the methodological basis for the development of a new method for assessing the quality of food eggshells, which is needed to prevent losses and prevent contamination with Salmonella.