Tuning Rheology of Gelled Emulsions by Incorporation of Betalain and ¿-Carotene: Implications for Bioink Design

• Grant number: 25/22942-5
• Support Opportunities: Scholarships abroad - Research Internship - Doctorate
• Start date: February 01, 2026
• End date: January 31, 2027
• Field of knowledge: Agronomical Sciences - Food Science and Technology - Food Engineering
• Principal Investigator: Rosiane Lopes da Cunha
• Grantee: Ana Elisa Ramos Magalhães
• Supervisor: Giana Estela de Andrade Almeida Perre
• Host Institution: Faculdade de Engenharia de Alimentos (FEA). Universidade Estadual de Campinas (UNICAMP). Campinas , SP, Brazil
• Institution abroad: Agroparistech, Campus Agro Paris-Saclay, France
• Associated to the scholarship: 24/01241-6 - Mechanical, tribological properties and digestibility of structures obtained by 3D printing of emulgels, BP.DR

Abstract

Three-dimensional printing has emerged as a promising technique for producing customized foods and meals enriched with bioactive compounds. However, even in small concentrations, bioactive compounds can alter the structure of the matrices due to interactions between the components. In this sense, the bioink matrix plays a fundamental role from a functional and technological perspective. For food applications, gelled emulsions are promising bioinks due to their unique structure, composed of a soft solid matrix with interesting rheological properties. As multiphase systems, they enable the simultaneous encapsulation of hydrophilic and lipophilic compounds, such as betalain and b-carotene, which can act synergistically to enhance the functionality of the products in which they are incorporated. In order to assess functional efficiency, these systems will be characterized in terms of encapsulation efficiency and structural modification under processing and storage conditions. For good printing performance, the bioink must exhibit adequate rheological properties, such as easy flow during the process and rapid structural recovery after exiting the extruder nozzle. After structure formation, small-amplitude oscillatory shear (SAOS) rheology can be applied to characterize the bioink matrix under rest-like conditions, without disrupting the formed structure. However, the extrusion process is inherently complex, subjecting the material to high deformations and stress, which can alter both the viscous properties and the elastic network. In this context, in addition to determining flow curves, large-amplitude oscillatory shear (LAOS) rheology allows deeper insight into the relationship between elastic microstructure breakdown and processing under the nonlinear mechanical conditions. Furthermore, Computational Fluid Dynamics (CFD) can provide valuable insights into the influence of different printing parameters on flow behavior and printing accuracy. In this work, gelled emulsions stabilized by pea protein and xanthan gum will be produced, wherein betalain will be incorporated into the aqueous phase and ¿-carotene into the lipid phase, individually or in combination. To advance the development of 3D printing processes, this study will comprehensively evaluate and model the rheological behavior of gelled emulsions under 3D printing conditions - from syringe loading to equilibrium gelled structure - in order to establish correlations with the micro- and macrostructural characteristics of the bioinks. A special focus will be addressed on high-strain processes, combining quantitative analysis of nonlinear LAOS behavior with the development of a CFD model to link flow behavior during extrusion to printing accuracy.