Relationship between microstructure formation and in vitro starch digestibility in baked gluten-starch matrices

José D Torres; Verónica Dueik; Ingrid Contardo; David Carré; Pedro Bouchon

doi:10.1016/j.fochx.2024.101347

Relationship between microstructure formation and in vitro starch digestibility in baked gluten-starch matrices

Food Chem X. 2024 Apr 3:22:101347. doi: 10.1016/j.fochx.2024.101347. eCollection 2024 Jun 30.

Authors

José D Torres^{1

2}, Verónica Dueik³, Ingrid Contardo^{4

5}, David Carré³, Pedro Bouchon^{1

6}

Affiliations

¹ Department of Chemical and Bioprocess Engineering, Pontificia Universidad Católica de Chile, PO Box 306, Santiago 6904411, Chile.
² School of Agroindustrial Engineering, Universidad del Sinú Cartagena, Sede Plaza Colón, Avenida El Bosque, Transversal 54 N° 30-729, Cartagena 130014, Colombia.
³ Comercial e Industrial SOLUTEC Ltda, Almirante Churruca 3130, Santiago 8370653, Chile.
⁴ Biopolymer Research and Engineering Lab (BiopREL), School of Nutrition and Dietetics, Faculty of Medicine, Universidad de los Andes, Monseñor Álvaro del Portillo 12.455, Chile.
⁵ Centre for Biomedical Research and Innovation (CIIB), Universidad de los Andes, Monseñor Álvaro del Portillo 12.455, Las Condes, Chile.
⁶ Centro de Investigación en Nanotecnología y Materiales Avanzados (CIEN-UC), Pontificia Universidad Católica de Chile, PO Box 306, Santiago 6904411, Chile.

Abstract

Increased prevalence of diabetes prompts the development of foods with reduced starch digestibility. This study analyzed the impact of adding soluble dietary fiber (inulin-IN; polydextrose-PD) to baked gluten-starch matrices (7.5-13%) on microstructure formation and in vitro starch digestibility. IN and PD enhanced water-holding capacity, the hardness of baked matrices, and lowered water activity in the formulated matrices, potentially explaining the reduced starch gelatinization degree as IN or PD concentration increased. A maximum gelatinization decrease (26%) occurred in formulations with 13% IN. Micro-CT analysis showed a reduction in total and open porosity, which, along with the lower gelatinization degree, may account for the reduced in vitro starch digestibility. Samples with 13% IN exhibited a significantly lower rapidly available glucose fraction (8.56 g/100 g) and higher unavailable glucose fraction (87.76 g/100 g) compared to the control (34.85 g/100 g and 47.59 g/100 g, respectively). These findings suggest the potential for developing healthier, starch-rich baked foods with a reduced glycemic impact.

Keywords: Acetic acid (PubChem CID 176); Baking; Benzoic acid (PubChem CID: 243); Gelatinization; Hydrochloric acid (PubChem CID: 313); Inulin; Inulin (PubChem CID: 132932783); Invertase (PubChem SID 348266890); Pancreatin (PubChem SID 7,980,246); Pepsin (PubChem CID: 17397483); Polydextrose; Polydextrose (PubChem CID: 71306906); Potassium hydroxide (PubChem CID: 14797); Sodium acetate 3-Hydrate (PubChem CID: 23665404); Starch digestibility; X-ray micro-computed tomography.