Sugar-free Chocolates: Physical Properties of Brazilian Market Samples

Abstract

Understanding local trends is essential for assessing consumer preferences and openness to new products. This study compared nine commercial dark and milk chocolates (with and without sucrose) from the Brazilian market, evaluating color, calorimetric, rheological, and texture properties. One-way ANOVA assessed overall differences, with significant results (p < 0.05) further examined by Tukey’s test. Texture, measured via normalized bending stress (σflex) to reduce geometric artifacts, showed dark chocolates with greater breakage resistance than milk chocolates; the xylitol sample (D) was the most resistant. All samples exhibited pseudoplastic behavior, confirmed by the Casson model (R² > 0.98). Milk chocolates generally showed higher rheological values (Casson yield stress, plastic viscosity, thixotropy), whereas dark chocolate Sample D (xylitol) had a significantly lower plastic viscosity (1.37 Pa·s). Sucrose substitution significantly altered color: dark chocolate Sample C (maltitol) presented a higher b* (8.54 ± 0.25) and lower Whiteness Index (20.59 ± 0.33), while milk chocolate Sample I (maltitol/polydextrose) differed from the control (E) in all color parameters, with a lower L* (31.44 ± 0.26). In calorimetry, sugar-free dark chocolates showed lower carbonization peak temperatures (e.g., 148.72 °C for Sample B) than the sucrose control (A, 219.44 °C), and milk chocolate Samples I and F did not carbonize within the 15–250 °C range. In conclusion, although sweetener choice, formulation, and ingredients induced statistically significant differences (p < 0.05) in flow limits and physical characteristics, the commercial products maintained quality control comparable to the sugar-based control commonly sold in Brazil.