Optimization of acorn (Quercus suber L.) muffin formulations: Effect of using hydrocolloids by a mixture design approach.

Acorn flour was used as a gluten-free ingredient to produce acorn muffins. Interaction effects between xanthan (X), carboxymethyl cellulose (CMC) and κ-carrageenan (κ-C) (0-0.3%) on the height and textural parameters of the formulated acorn flour muffins were investigated using a mixture design approach. Each studied parameter was optimized individually. Then, an optimal formulation giving a product with characteristics as close as possible to those of a wheat flour muffin sample was determined. Results revealed that addition of each hydrocolloid separately, or their ternary combination improved the muffin height. Optimal height value was predicted to reach 3.96 cm when using 26.8% X, 50.5% CMC and 22.7% κ-C. As regard to textural parameters (firmness, cohesiveness, springiness and adhesiveness), presence of the three hydrocolloids had an antagonistic effect. The best hydrocolloids mixture giving optimal height (3.92 cm), firmness (3.19 N) and adhesiveness (0.66 N) was that containing 20.5% X and 79.5% CMC.