Localization and modeling of reaction and diffusion to explain folate behavior during soaking of cowpea

Fanny Coffigniez (1) , Michael Rychlik (1) , Christine Sanier (2, 3, 4) , Christian Mestres (1, 5) , Lisa Striegel (6) , Philippe Bohuon (1) , Aurélien Briffaz (1, 5)

1 UMR Qualisud - Démarche intégrée pour l'obtention d'aliments de qualité
2 UMR AGAP - Amélioration génétique et adaptation des plantes méditerranéennes et tropicales
3 PHIV - Plateforme d'histocytologie et d'imagerie cellulaire végétale
4 Cirad-BIOS - Département Systèmes Biologiques
5 Cirad-PERSYST - Département Performances des systèmes de production et de transformation tropicaux
6 TUM - Technische Universität Munchen - Technical University Munich - Université Technique de Munich

A first modeling approach was used to understand the behavior of folate in cowpea seeds during soaking at different temperatures (30 degrees C, 60 degrees C and 95 degrees C). Folic acid, 10-formylfolic acid, 5-methyltetrahydrofolate, and 5-formyltetrahydrofolate were quantified in both the seeds and the soaking water during the process. A 2D-axisymmetric seed soaking simulator was then built considering these 4 folate vitamers to simultaneously describe diffusion, oxidation and interconversion of the single vitamers. The model adjustments revealed the predominance of folate diffusion at 60 degrees C and 95 degrees C (apparent diffusivity 2-3 x 10(-11) m(2) s-(1))whereas at 30 degrees C enzymatic interconversions of all vitamers into 5-methyltetrahydrofolate were observed (reaction rate of 8.0 x 10(-5) s(-1) for 5-formyltetrahydrofolate). The results of this study allow us to recommend a preliminary soaking step to retain folate in seeds and to improve the bioavailability of folates for human nutrition.

Mots clés: Folates; Legume; Diffusion; Reaction kinetics; Soaking; Interconversion

Domaines: Sciences du Vivant [q-bio]

Fanny Coffigniez, Michael Rychlik, Christine Sanier, Christian Mestres, Lisa Striegel, et al.. Localization and modeling of reaction and diffusion to explain folate behavior during soaking of cowpea. Journal of Food Engineering, 2019, 253, pp.49 - 58. ⟨10.1016/j.jfoodeng.2019.02.012⟩. ⟨hal-03485714⟩