Use of granules and free salts for Fe and Zn fortification of leafy vegetables: Improvements in trace element bioaccessibility and fulfillment of Dietary Reference Intakes

J Martínez-Castro; F Cámara-Martos; A Moreno-Ortega; M Victorio-Sánchez; A Krstova; J Almeida Lopes; F Pérez-Rodríguez

doi:10.1016/j.jtemb.2023.127181

Use of granules and free salts for Fe and Zn fortification of leafy vegetables: Improvements in trace element bioaccessibility and fulfillment of Dietary Reference Intakes

J Trace Elem Med Biol. 2023 Jul:78:127181. doi: 10.1016/j.jtemb.2023.127181. Epub 2023 Apr 26.

Authors

J Martínez-Castro¹, F Cámara-Martos², A Moreno-Ortega¹, M Victorio-Sánchez¹, A Krstova³, J Almeida Lopes⁴, F Pérez-Rodríguez¹

Affiliations

¹ Departamento de Bromatología y Tecnología de los Alimentos, Universidad de Córdoba, Campus Universitario de Rabanales, Edificio C-1, 14014 Córdoba, España.
² Departamento de Bromatología y Tecnología de los Alimentos, Universidad de Córdoba, Campus Universitario de Rabanales, Edificio C-1, 14014 Córdoba, España. Electronic address: bt2camaf@uco.es.
³ Faculty of Pharmacy, University of Ljubljana, Aškerčeva cesta 7, 1000 Ljubljana, Slovenia.
⁴ Research Institute for Medicines (iMed.ULisboa), Faculdade de Farmácia da Universidade de Lisboa, Av. Prof. Gama Pinto, 1649-003 Lisboa, Portugal.

PMID: 37163823
DOI: 10.1016/j.jtemb.2023.127181

Abstract

Background: Leafy vegetables represent an excellent dietary source of trace elements such as Fe and Zn. Nevertheless, Fe and Zn bioaccessibility can lessen due to a high concentration of anti-nutritional compounds. The encapsulation of Fe and Zn salts as granules could be used to fortify these leafy vegetables.

Method: Three leafy vegetables, spinach, Swiss chard and Ethiopian mustard were fortified with iron sulfate and zinc sulfate as granules and free salts in order to test the improvements in the bioaccessibility and fulfillments of DRIs. Fe and Zn granules were prepared in a fluidized bed granulator. A probabilistic analysis was performed, using experimental data, to assess bioaccessible intake and fulfillments of DRIs in European populations.

Results: Fe contents ranged between 4.8 mg/100 g of Ethiopian mustard to 157.4 mg/100 g of spinach. Fe and Zn bioaccessibility percentages were low for Swiss chard and spinach without fortification. Fortification with granules improved Fe bioaccessibility of these latter vegetables (196 and 223 mg/100 g). Zn contents in samples without fortification ranged between 2.3 mg/100 g for Ethiopian mustard and 7.4 mg/100 g for spinach. Zn fortification as granules improved Zn bioaccessibility for the three vegetables studied. Thus, Zn bioccessible concentrations ranged between 17.4 and 108 mg/100 g for the solubility assay and between 5.9 and 31.1 mg/100 g for the dialyzability assay. Besides, the probability analysis showed that fortification had a better performance in meeting DRIs for those populations with higher consumption levels of leafy vegetables.

Conclusions: The probability analysis demonstrated that fortification can be a suitable strategy to meet DRIs for both trace elements, which was especially remarkable for Fe. Fortification with granule was more effective in most the cases, although for Ethiopian mustard, free salt of Fe showed a better performance.

Keywords: Bioaccessibility; Fortification; Granulation; Iron; Leafy vegetables; Zinc.

MeSH terms

Recommended Dietary Allowances
Salts
Trace Elements* / analysis
Vegetables
Zinc / analysis

Substances

Trace Elements
Salts
Zinc