TY - JOUR
T1 - Effect of the degree of substitution on the hydrophobicity, crystallinity, and thermal properties of lauroylated amaranth starch
AU - Espinosa-Solis, Vicente
AU - García-Tejeda, Yunia Verónica
AU - Leal-Castañeda, Everth Jimena
AU - Barrera-Figueroa, Víctor
N1 - Publisher Copyright:
© 2020 by the authors. Licensee MDPI, Basel, Switzerland.
PY - 2020/11
Y1 - 2020/11
N2 - In this paper, we consider amaranth starch extracted from the seeds of Amaranthus hypochondriacus L. An amphiphilic character is conferred to the starch by a chemical modification, which involves an esterification by lauroyl chloride at three modification levels. The degree of substitution (DS) after the modification ranged from 0.06 to 1.16. X-ray photoelectron spectroscopy analysis confirmed the presence of fatty acyl chains on the surface of the esterified starches. The hydrophobicity of starches was confirmed by their adsorption isotherms, which showed a decrease in the moisture adsorption of lauroylated as DS increased. X-ray diffraction analysis revealed a higher crystallinity, which was observed in the two samples subjected to the highest levels of modification. A higher crystallinity is related to a higher gelatinization enthalpy. These results are in agreement with the thermal characterization obtained by differential scanning calorimetry (DSC). An inhibition of the retrogradation properties of lauroylated amaranth starches was also observed.
AB - In this paper, we consider amaranth starch extracted from the seeds of Amaranthus hypochondriacus L. An amphiphilic character is conferred to the starch by a chemical modification, which involves an esterification by lauroyl chloride at three modification levels. The degree of substitution (DS) after the modification ranged from 0.06 to 1.16. X-ray photoelectron spectroscopy analysis confirmed the presence of fatty acyl chains on the surface of the esterified starches. The hydrophobicity of starches was confirmed by their adsorption isotherms, which showed a decrease in the moisture adsorption of lauroylated as DS increased. X-ray diffraction analysis revealed a higher crystallinity, which was observed in the two samples subjected to the highest levels of modification. A higher crystallinity is related to a higher gelatinization enthalpy. These results are in agreement with the thermal characterization obtained by differential scanning calorimetry (DSC). An inhibition of the retrogradation properties of lauroylated amaranth starches was also observed.
KW - Adsorption isotherms
KW - Amaranth starch
KW - Lauroylation
KW - Thermal properties
UR - http://www.scopus.com/inward/record.url?scp=85094563214&partnerID=8YFLogxK
U2 - 10.3390/polym12112548
DO - 10.3390/polym12112548
M3 - Artículo
C2 - 33143285
AN - SCOPUS:85094563214
SN - 2073-4360
VL - 12
SP - 1
EP - 15
JO - Polymers
JF - Polymers
IS - 11
M1 - 2548
ER -