Development of Gluten-Free Cakes Using Protein Concentrate Obtained from Cold-Pressed Terebinth (Pistacia terebinthus L.) Oil By-Products

The present research aimed to incorporate terebinth seed protein into gluten-free cakes in order to increase their protein content and improve their technological properties. The terebinth protein replaced the rice flour-corn starch mixture used in control cakes at varying levels (3%, 6%, 9%, and 12%). The rheological properties of the cake batters were evaluated, along with the physicochemical attributes, textural properties, sensory attributes, and oxidative stability of the baked cakes. As the protein concentration increased, the consistency index of the cake batters also increased. All batters showed shear-thinning behavior, indicating pseudoplastic fluid behavior, and showed a viscoelastic nature reflected by the storage modulus (G') exceeding the loss modulus (G″). Both G' and G″ values increase with increasing protein content. The softest texture was observed in the control cake produced with wheat flour, followed by the cakes with 3% and 6% protein addition, while higher protein levels (9% and 12%) resulted in firmer cakes. Furthermore, oxidative stability improved with a higher level of protein. The addition of protein did not negatively affect sensory quality across all measured parameters. This study demonstrates the potential of terebinth protein to enhance the protein content and oxidative stability of gluten-free cakes that maintain their sensory attributes.