Technological Challenges of Spirulina Powder as the Functional Ingredient in Gluten-Free Rice Crackers

Technological issues with the production of gluten-free rice crackers with spirulina powder were examined in this work through their rheological, textural, color, sensory, and nutritional aspects. A part of gluten-free whole-grain rice flour was replaced with 5, 10, and 15% spirulina powder in an appropriate recipe for crackers. The rheological analysis presented obtained dough samples as viscoelastic systems with dominant elastic components (G′ > G″ and Tan δ = G″/G′ is less than 0). The addition of spirulina contributed to a softer dough consistency according to a statistically significant (p < 0.5) decrease of Newtonian viscosity during the creep phase for a maximum of 43.37%, compared to the control dough. The 10 and 15% quantities of spirulina powder led to a statistically significant (p < 0.5) increase in the viscoelastic parameter Jmax, which indicated a greater dough adaptability to stress. The textural determination of the dough pointed statistically significantly (p < 0.05) to decreased dough hardness and improved dough extensibility and confirmed all rheological measurements with high correlation coefficients, indicating good physical dough properties during processing. Spirulina certainly affected the change in the color of the dough from a yellow-white to intense green, which also had a significant impact on the sensory quality of the baked crackers. Many sensory properties of the crackers were improved by the addition of and increasing amounts of spirulina (appearance, brittleness, hardness, graininess, and stickiness). The results for the dough and for the final crackers pointed to very good technological aspects for the development of a gluten-free bakery product with high nutritional value, such as increased polyphenolic content (with the majority of catechins), protein, total dietary fibers, and mineral content compared to the control sample.