Innovative Functional Gummies with Caffeine and Collagen: Formulation and Physicochemical Properties

The aim of this study was to develop and investigate the effect of the freeze-drying and coating on the physicochemical properties of gummies enriched with caffeine and collagen hydrolysate. Gelatin-based gummies in which sucrose was replaced with xylitol were subjected to freeze-drying and coated with a shellac layer. The products were then evaluated for water activity, dry matter content, textural properties, color, and the gel mass pH. Fourier transform infrared spectra (FTIR) and thermogravimetric analysis (TGA) were performed to investigate structural changes and thermal stability. Freeze-drying reduced the water activity from 0.679 to 0.486 and increased the dry matter content from 64.50% to 84.20%, thereby potentially improving product stability. The use of a shellac coating influenced textural properties, which remained characteristic of gummy products even after freeze-drying, and reduced color changes after freeze-drying from 4.88 units to 1.77 units. FTIR confirmed the presence of characteristic functional groups associated with the formulation components and provided evidence of successful incorporation of caffeine into the gummy matrix. Furthermore, thermogravimetric analysis (TGA) demonstrated the high thermal stability of the developed formulations.