Structural and rheological properties of polysaccharides from mango (Mangifera indica L.) pulp.
The structure and rheological properties of water-soluble polysaccharides from industrialized mango pulp were investigated. Soluble fraction (SF) 2 was heterogeneous on high performance size exclusion chromatography, giving two peaks as determined by multi-angle laser light scattering and refractive index detectors. The presence of starch in SF2 was demonstrated by a positive iodine reaction and by 13C nuclear magnetic resonance (NMR) spectroscopy. The presence of pectic polysaccharides was shown by a calorimetric method, 13C-NMR spectroscopy and carboxyl reduction. The main pectic polysaccharide was polygalacturonic acid; type I rhamnogalacturonan was also detected. Analysis of the rheological properties of SF2 showed a pseudoplastic behavior up to 3 g x l(-1). 'Creep and recovery' tests and analysis performed under a dynamic state revealed a weak gel character for solutions at concentrations of 15, 20 and 30 g x l(-1).
Iagher
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F
Department of Biochemistry, Universidade Federal do Paraná, C.P. 19046, 81531-990, PR, Curitiba, Brazil.
Reicher
F
F
Ganter
J L M S
JL
D007455:Iodine / Q000737:chemistry; D009682:Magnetic Resonance Spectroscopy; D031022:Mangifera; D010368:Pectins / Q000737:chemistry; D011134:Polysaccharides / Q000737:chemistry*; D013997:Time Factors
D011134:Polysaccharides; D010368:Pectins; D007455:Iodine; C003181:polygalacturonic acid