Texture and Microstructure of Gelatin/Corn Starch-Based Gummy Confections

Abstract

Texture of gummy gels prepared with gelatin and acid modified corn starch (AMCS) was quantified by instrumental techniques and the gel microstructure was examined by confocal laser scanning microscopy (CLSM) and scanning electron microscopy (SEM). Gelatin:AMCS gummy gels were divided in two groups: Group 1, containing different gelatin (0–10 wt%) and AMCS (0–10 wt%) concentrations, totalizing 10 wt% solids; and Group 2, which was prepared with a fixed gelatin concentration (8 wt%) and varied AMCS concentrations (0–5 wt%). All gummy gels were formulated with maltitol syrup and xylitol, shaped in cylindrical molds and submitted to instrumental texture profile analysis (TPA) tests and colorimetric analysis. Group 1 pure starch gels (10 % AMCS) presented the highest stringiness and adhesiveness. In samples of Group 2 the introduction of AMCS dramatically changed the structure of the gelatin gels. Thermodynamic incompatibility was evident even at the lowest AMCS concentration. Moreover, increasing AMCS concentrations lead to an increase in the number of hollow zones including starch granules inside them. In addition, introduction of AMCS in the samples of Group 2 caused an increase in hardness and opacity and a decrease in stringiness and adhesiveness. On the other hand, results from TPA tests showed that the addition of AMCS to gelatin gels in suitable proportions can be a feasible alternative in the formulation of gummy confections.