A novel rheometer-based method to determine melting properties of gelatin-based gummies

In this study, a novel rheometer-based method was explored to determine the melting point of gummy, which is one of the most consumed confectionery products. For this purpose, the melting points of the products were determined by performing onset analysis on the graph of the obtained gap versus temperature. Heating rate and sample thickness parameters were used to develop the novel method. Likewise, the data of the crossover point of G′ and G′′, which is one of the classical methods for the determination of melting, were also taken. In order to verify the obtained melting points, time sweep tests in the rheometer at a constant temperature, analysis of holding in the oven and water bath, and the determination of the yield stress values at various temperatures were carried out. In addition, thermograms of the samples obtained from differential scanning calorimetry (DSC), their microstructures at various temperatures with polarized light microscopy (PLM), and thermal degradation curves with thermogravimetric analyzes (TGA) were also examined to compare results. Also, moisture content and texture profile analyzes of the samples were determined. As a result of the research, it can be evaluated that the developed method detects the melting point of a soft candy with a sensitivity of 1 °C when working with a temperature increase rate of 1 °C/min and a thickness of 4000 µm. After the method parameters were obtained, to observe the commercial usability of the method, two gelatin-based soft candies were purchased, and the melting points were determined by both the developed method and the verification analysis, and the effectiveness of the method was proven. As a result of the study, the evaluation of the gap-temperature plot with onset analysis has been tried as a new approach and has brought a different perspective to the melting temperature analysis. The novel rheometer-based method developed to determine the melting temperature within the scope of the thesis study provides ease of use and short-term detection with sensitive and reproducible analyses. In addition, it has come to the forefront as it allows the studied materials to be used in solid form.