Effect of the alkaline treatment on the ultrastructure of C-type starch granules.
The effect of alkaline treatment on the ultrastructure of C-type starch granules was investigated during the alkaline extraction of Araucaria angustifolia (pinhao) starch. The efficiency in protein removal was evaluated using intrinsic fluorescence and Kjeldahl's method. In parallel, morphological changes of starch granules were observed using scanning electron microscopy and atomic force microscopy. The starch crystallinity was monitored by wide-angle X-ray scattering and the lamellar structure was studied by small-angle X-ray scattering (SAXS). The paracrystalline model was employed to interpret the SAXS curves. It was found that the granular organization was significantly altered when alkaline solutions were used during the extraction. A partial degradation of B-type allomorph of starch and a significant compression of semicrystalline growth rings were observed.
Programa de Pos-Graduacao em Engenharia Química, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil.
Roberta C S
RC
Thys
Harry
H
Westfahl
Caciano P Z
CP
Noreña
Lígia D F
LD
Marczak
Nádya P
NP
Silveira
Mateus B
MB
Cardoso
D000468:Alkalies / Q000737:chemistry*; D003460:Crystallization; D013213:Starch / Q000737:chemistry* / Q000302:isolation & purification; D014961:X-Ray Diffraction
D000468:Alkalies; D013213:Starch