TY - JOUR

T1 - Impact of Physicochemical Modifications in Casein Promoted by UV-C on the Peptide Profile of Gastric Digestion and the Transepithelial Transport of Peptides

AU - Brasil Morais, Aline Teixeira do Brasil

AU - Morais, Sinara T.B.

AU - Feitor, Jessica F.

AU - Santos, Willy Glen

AU - Gomes da Silva Catunda, Lucas

AU - Walkling-Ribeiro, Markus

AU - Ahrne, Lilia

AU - Cardoso, Daniel R.

N1 - Publisher Copyright: © 2023 American Chemical Society.

PY - 2023

Y1 - 2023

N2 - Caseins are the main proteins in milk, and their structure and spatial conformation are responsible for their slow digestion rate. The release of bioactive and β-casomorphin peptides from casein digestion may induce allergic responses during consumption. Spectroscopic techniques were used to observe the structural changes in casein conformation induced by Ultraviolet light irradiation (UV-C). Raman spectroscopy results showed more pronounced peaks at 618 and 640 cm-1 for phenylalanine and tyrosine moieties of the photolyzed micellar casein, respectively, suggesting changes in the micelle structure. The decrease in the intensity of Raman signals for tryptophan and tyrosine corroborates to the UV-C-induced modifications of the micelle structure. Particle size distribution showed a decrease in the average micelle size after 15 min of UV-C exposure, while low-temperature, long-time (LTLT) pasteurization led to the formation of large aggregates, as observed by atomic force microscopy. UV-C did not impact the formation or transport of peptides, as observed by using the Caco-2 cell as a model for peptide absorption. However, the absence of the opioid peptide SRYPSY from κ-casein and only 20% of the concentration of opioid peptide RYLGY were noted. This work demonstrated that UV-C can be utilized to induce the physicochemical modification of dairy products, promoting a higher digestion rate and reducing allergenicity.

AB - Caseins are the main proteins in milk, and their structure and spatial conformation are responsible for their slow digestion rate. The release of bioactive and β-casomorphin peptides from casein digestion may induce allergic responses during consumption. Spectroscopic techniques were used to observe the structural changes in casein conformation induced by Ultraviolet light irradiation (UV-C). Raman spectroscopy results showed more pronounced peaks at 618 and 640 cm-1 for phenylalanine and tyrosine moieties of the photolyzed micellar casein, respectively, suggesting changes in the micelle structure. The decrease in the intensity of Raman signals for tryptophan and tyrosine corroborates to the UV-C-induced modifications of the micelle structure. Particle size distribution showed a decrease in the average micelle size after 15 min of UV-C exposure, while low-temperature, long-time (LTLT) pasteurization led to the formation of large aggregates, as observed by atomic force microscopy. UV-C did not impact the formation or transport of peptides, as observed by using the Caco-2 cell as a model for peptide absorption. However, the absence of the opioid peptide SRYPSY from κ-casein and only 20% of the concentration of opioid peptide RYLGY were noted. This work demonstrated that UV-C can be utilized to induce the physicochemical modification of dairy products, promoting a higher digestion rate and reducing allergenicity.

KW - in vitro protein digestibility

KW - micellar casein isolate

KW - particle size and spectroscopic analyses

KW - peptide sequencing

KW - ultraviolet light irradiation

U2 - 10.1021/acs.jafc.3c00392

DO - 10.1021/acs.jafc.3c00392

M3 - Journal article

C2 - 37157171

AN - SCOPUS:85159572247

VL - 71

SP - 7495

EP - 7507

JO - Journal of Agricultural and Food Chemistry

JF - Journal of Agricultural and Food Chemistry

SN - 0021-8561

IS - 19

ER -