TY - JOUR
T1 - Structural changes in popped sorghum starch and their impact on the rheological behavior
AU - Cabrera-Ramírez, A. H.
AU - Morales-Sánchez, E.
AU - Méndez-Montealvo, G.
AU - Velazquez, G.
AU - Rodríguez-García, M. E.
AU - Villamiel, Mar
AU - Gaytán-Martínez, M.
N1 - Publisher Copyright:
© 2021 Elsevier B.V.
PY - 2021/9/1
Y1 - 2021/9/1
N2 - Sorghum has been used to expand snacks such as pop sorghum. However, it is still unknown how the structural changes during the popping affect its rheological and functional properties. This study evaluated the structural changes of popped sorghum starch (PS) and their impact on rheological behavior. Moisture sorghum was adjusted to 11, 15, and 20% before popped. Morphology, X-ray pattern (XRP), infrared spectra (IR), thermal properties, and rheological behavior before and after popping were evaluated. Micrographs showed a honeycomb-like structure in PS. XRP showed partial damage to the orthorhombic crystals of the sorghum starch after PS, while the growth of crystalline lamellae was also generated (13.08 and 20.01°). IR showed structural damage as the signal at 1045 cm−1 disappeared in PS. The IM increased to gelatinization of the starch. The rheological behavior of PS displayed better thermal stability, with the lowest breakdown (25 ± 3.5 cP), setback (253 ± 11.3 cP), and final (1337 ± 5.7 cP) viscosity. The consistency coefficient k and flow behavior index n increase, meaning a loss of the pseudoplastic character. Viscoelastic properties increased in PS, suggesting the formation of cross-links and a stable matrix. Correlation analysis showed a strong relationship between structural changes and the rheological behavior of PS.
AB - Sorghum has been used to expand snacks such as pop sorghum. However, it is still unknown how the structural changes during the popping affect its rheological and functional properties. This study evaluated the structural changes of popped sorghum starch (PS) and their impact on rheological behavior. Moisture sorghum was adjusted to 11, 15, and 20% before popped. Morphology, X-ray pattern (XRP), infrared spectra (IR), thermal properties, and rheological behavior before and after popping were evaluated. Micrographs showed a honeycomb-like structure in PS. XRP showed partial damage to the orthorhombic crystals of the sorghum starch after PS, while the growth of crystalline lamellae was also generated (13.08 and 20.01°). IR showed structural damage as the signal at 1045 cm−1 disappeared in PS. The IM increased to gelatinization of the starch. The rheological behavior of PS displayed better thermal stability, with the lowest breakdown (25 ± 3.5 cP), setback (253 ± 11.3 cP), and final (1337 ± 5.7 cP) viscosity. The consistency coefficient k and flow behavior index n increase, meaning a loss of the pseudoplastic character. Viscoelastic properties increased in PS, suggesting the formation of cross-links and a stable matrix. Correlation analysis showed a strong relationship between structural changes and the rheological behavior of PS.
KW - Popped sorghum starch
KW - Rheology
KW - Structural characteristics
UR - http://www.scopus.com/inward/record.url?scp=85110562184&partnerID=8YFLogxK
U2 - 10.1016/j.ijbiomac.2021.07.018
DO - 10.1016/j.ijbiomac.2021.07.018
M3 - Artículo
SN - 0141-8130
VL - 186
SP - 686
EP - 694
JO - International Journal of Biological Macromolecules
JF - International Journal of Biological Macromolecules
ER -