Enhanced bioactive and rheological properties of 3D xanthan gum matrices using grape by-product-based particles obtained by spray drying

Abstract

The development of innovative 3D printing matrices enriched with bioactive compounds seamlessly integrates sustainable practices with cutting-edge advancements in functional material design. In this sense, the main objectives of this study were to produce particles enriched with grape pomace extract through spray drying and to evaluate their effect on the active and rheological properties of matrices based on xanthan gum for 3D printing. The extract, obtained by pressurized liquid extraction (PLE), was characterized regarding total phenolic compounds (TPC), anthocyanin content (TA), and antioxidant activity (AA): 3.58 ± 0.02 μg GAE/mL of extract, 219.3 ± 32.2 μg AT/mL of extract and 6.4 ± 0.5 nmol FeSO₄/mL of extract, respectively. The extract was mixed with maltodextrin (10 % w/v) and spray dried, resulting in spherical microparticles containing: 3.5 ± 0.5 mg GAE/g, 514.1 ± 28.5 μg TA/g and 86.5 ± 4.5 μmol FeSO₄/g. The microparticles were applied in two formulations of gels for 3D printing using xanthan gum and sodium alginate. The samples demonstrated an increased consistency index, storage modulus (G’) value, and resistance to deformation with the addition of particles. The printed particle samples exhibited behavior in accordance with the rheological analysis, showing increased viscoelasticity in comparison to the control, since they demonstrated improved concordance with the computer-aided design (CAD) software models. This suggests that the phenolic compounds from grape pomace extracts interact with xanthan gum, creating matrices suitable for 3D printing with active properties. These matrices have potential applications in various fields, such as anthocyanin-based pH indicators, nutraceuticals, and functional foods.