Investigation of average crosslink distance and physicochemical properties of gummy candy during storage: Effect of formulation and storage temperature

Texture is linked to food structure at micro- and macro-levels. The most effective way to manipulate gel texture is to change the number of crosslinks per unit volume. Polymer concentration and type can be changed or the amount of evaporated water can be adjusted to achieve this. Gummy candy is a good food model to investigate texture due to the presence of versatile polymer gelling agents. The estimation of average cross-link distance is a good approach to monitor candy texture. Physicochemical properties are useful indicators showing storage stability. In this study, gummy candies were prepared with different glucose sirup:sucrose ratios (1.1 and 1.5), starch (0% and 1.5%), and gelatin (3% and 6%) concentrations. Texture (hardness), moisture content, water activity (aw), total soluble solids (TSS), and pH were measured. Candies were stored at 10, 20, and 30 °C for 12 weeks and at ambient temperatures of 15–22 °C for 52 weeks. Gelatin concentration, moisture content, storage time, and temperature affected hardness. At 1.5 glucose sirup:sucrose ratio, average cross-link distance decreased after 10 °C storage for 3% gelatin level and it increased after 20 and 30 °C storage for 6% gelatin and 0% starch level; however, it did not change for 15–22 °C storage. Moisture content, aw, TSS, and pH were affected by glucose sirup:sucrose ratio. A Weibullian model was used to express quality changes, and physicochemical indicators did not have an integer kinetic order. Tracking of physicochemical properties and texture with average cross-link distance calculation and modeling is useful for storage stability studies showing the quality of food gel products.