[email protected]

Journal Pre-proofs
Impact of cooking and nixtamalization on the bioaccessibility and antioxidant
capacity of phenolic compounds from two sorghum varieties
Ivan Luzardo-Ocampo, Aurea K. Ramírez-Jiménez, Angel H. Cabrera-Ramirez,
N. Rodríguez-Castillo, Rocio Campos-Vega, Guadalupe Loarca-Piña, Marcela
Gaytán-Martínez
PII: S0308-8146(19)31811-4
DOI: https://doi.org/10.1016/j.foodchem.2019.125684
Reference: FOCH 125684
To appear in: Food Chemistry
Received Date: 24 April 2019
Revised Date: 7 October 2019
Accepted Date: 8 October 2019
Please cite this article as: Luzardo-Ocampo, I., Ramírez-Jiménez, A.K., Cabrera-Ramirez, A.H., Rodríguez-Castillo,
N., Campos-Vega, R., Loarca-Piña, G., Gaytán-Martínez, M., Impact of cooking and nixtamalization on the
bioaccessibility and antioxidant capacity of phenolic compounds from two sorghum varieties, Food Chemistry
(2019), doi: https://doi.org/10.1016/j.foodchem.2019.125684
This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover
page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will
undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing
this version to give early visibility of the article. Please note that, during the production process, errors may be
discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
© 2019 Elsevier Ltd. All rights reserved.

1
Impact of cooking and nixtamalization on the bioaccessibility and antioxidant
capacity of phenolic compounds from two sorghum varieties
Ivan Luzardo-Ocampoa , Aurea K. Ramírez-Jiménezb, Angel H. Cabrera-Ramirezc, N.
Rodríguez-Castillod, Rocio Campos-Vegaa, Guadalupe Loarca-Piñaa , Marcela Gaytán-
Martíneza,*
a Programa de Posgrado en Alimentos del Centro de la República (PROPAC), Research
and Graduate Studies in Food Science, School of Chemistry, Universidad Autónoma de
Querétaro, Centro Universitario, Cerro de las Campanas S/N. Santiago de Querétaro,
Querétaro, C.P. 76010, México.
b Tecnológico de Monterrey, Escuela de Ingeniería y Ciencias, Centro de Biotecnología
FEMSA, Av. Eugenio Garza Sada 2501 Sur, C.P. 64849 Monterrey, NL, México
c Instituto Politécnico Nacional, CICATA-IPN Unidad Querétaro, Cerro Blanco No. 141,
Col. Colinas del Cimatario, C.P.76090, Santiago de Querétaro, Querétaro, México
d Facultad de Química, Universidad Autónoma de Querétaro. Centro Universitario, Cerro
de las Campanas S/N. Santiago de Querétaro, Querétaro, C.P. 76010, México.
*Corresponding Author: Marcela Gaytán Martínez ([email protected])
Authors’ e-mail:
I. Luzardo-Ocampo: [email protected]
A. Ramírez-Jiménez: [email protected]
A. H. Cabrera-Ramírez: [email protected]

2
N. Rodríguez- Castillo: [email protected]
R. Campos-Vega: [email protected]
G. Loarca-Piña: [email protected]

3
Abstract
Sorghum (Sorghum bicolor L. Moench) has been sparsely used as human food due to
certain anti-nutritional factors such as tannins that reduce its digestibility, although the
grain is an important source of bioactive compounds such as phenolic compounds (PCs).
This study aimed to assess the impact of cooking and alkaline cooking (nixtamalization) on
the bioaccessibility and antioxidant capacity of PCs of two sorghum varieties (white/red).
Nixtamalization was the most effective procedure for the reduction of tannins (74.3 %).
Gallic acid proved to be the most bioaccessible PC (6359 g/g). The total phenolics and
condensed tannins correlated with the antioxidant capacity (ABTS/DPPH; R2:0.30-0.43,
p<0.05). These results confirm the potential of thermal procedures to significantly modify
the bioaccessibility of sorghum compounds, enhancing their concentrations and reducing
anti-nutritional factors (tannins) while improving their antioxidant capacity.
Keywords: Sorghum (Sorghum spp.), phenolics, nixtamalization, in vitro gastrointestinal
digestion, antioxidant capacity.

4
Chemical compounds studied in this article: ABTS (PubChem CID: 9570474); Caffeic
acid (PubChemCID: 689043); (+)-Catechin (PubChemCID: 9064); Chlorogenic acid
(PubChemCID: 1794427); DPPH (PubChem CID: 2735032); Gallic acid (PubChem CID:
370); p-Coumaric acid (PubChemCID: 637542); Quercetin (PubChemCID: 5280343);
Rutin (PubChemCID: 5280805); Soda lime (PubChem CID: 66545795).
Abbreviations: ABTS: 2,2-azinobis-(3-ethylbenzothazoline-6-suphonic acid); ADMET:
Absorption, Distribution, Metabolism, Excretion and Toxicity; CE: (+)-catechin
equivalents; CTs: Condensed tannins; CRW: Cooked red sorghum; CWS: Cooked white
sorghum; DF: Digestible fraction; DPPH: 1,1-diphenyl-2-picrylhydrazyl; ER: Efflux ratio;
FLEX: Flexibility; GAE: Gallic acid equivalents; HPLC-DAD: High performance liquid
chromatography coupled to Diode Array Detector; INSATU: Saturation; INSOLU:
Solubility; LIPO: Lipophilicity; ME: Methanolic extract; NDF: Non-digestible fraction;
NRS1: Nixtamalized red sorghum with 10 g Ca(OH)2/kg flour; NWS1: Nixtamalized
white sorghum with 10 g Ca(OH)2/kg flour; Papp: Apparent permeability coefficient; PCA:
Principal component analysis; POLAR: Polarity; PCs: Phenolic compounds; RE: Rutin
equivalents; RRS: Raw red sorghum; RWS: Raw white sorghum; TF: Total flavonoids;
TPCs: Total phenolic compounds; TPSA: Topological polar surface area; WF: Water flux;
WLOGP: Wildman & Crippen atomistic method score.