Broadening of the Water Proton Line in High-Resolution Nuclear Magnetic Resonance Spectra of Starch Gels

Collison, R.; McDonald, M. P.

doi:10.1038/186548a0

Cited by 33 publications

(7 citation statements)

References 6 publications

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“…Rough rice samples, obtained from the Plant Breeding Department of the International Rice Research Institute (IRRI) and the Agronomy Department of the University of the Philippines at Los Baiios (UPLB), were dehulled in a T H U type Satake dehuller and milled in a TM-05 type Satake testing mill. The milled rice was ground for analysis in a Udy cyclone mill with 40-mesh sieve and analyzed for micro Kjeldahl nitrogen [7], and amylography [8]. The factor 5.95 was used to convert Kjeldahl nitrogen to crude protein.…”

Section: Methodsmentioning

confidence: 99%

Gel and Molecular Properties of Nonwaxy Rice Starch

Juliano

Perdon

1975

Starch Stärke

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A study of the factors that determine the gel consistency values of nonwaxy milled rice and rice starch showed that these values (in mm) were correlated negatively with the corresponding gel viscosities as measured with a Wells‐Brookfield viscometer. In 6 IRRI rice varieties and an intermediate amylose variety, C 4–63 G, amylopectin contributed more to gel viscosity than did the amylose fraction of the starch. Differences in gel viscosity were observed only at starch concentration of 40 mg in 2 ml 0.2‐N KOH or higher and were not simply related to differences in the intrinsic viscosity [η] of starch. However, gel consistency of starch was significantly correlated negatively with [η] of amylopectin. Gel viscosity was higher in KOH than in potassium acetate but the difference in viscosity was greater for the starch and amylopectin than for amylose.

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Section: Methodsmentioning

confidence: 99%

Gel and Molecular Properties of Nonwaxy Rice Starch

Juliano

Perdon

1975

Starch Stärke

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“…Continuous wave (C W) wide-line NMR methods can provide similar information. The line width of solid starch was estimated by the C W method to be > 16 kHz in early work (Collison and McDonald, 1960), although spectra were not shown. The CW method is rarely used and has significant disadvantages for motionally heterogeneous samples (Andrew, 1953) when compared with pulsed time domain and Fourier transform methods.…”

Section: Introductionmentioning

confidence: 99%

Detection of solid-like components in starch using cross-relaxation and Fourier transform wide line proton NMR methods

Wu¹,

Bryant²,

Eads³

1992

J. Agric. Food Chem.

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A new proton ('H) NMR method, nuclear magnetic cross-relaxation spectroscopy, permits sensitive detection of immobilized polymer in starch samples. The 'H cross-relaxation spectrum reflects the amount and relative rigidity of immobilized starch chains. Cross-relaxation integrated spectral intensities for freshly gelatinized waxy maize starch were found to depend sensitively on starch concentration above 10 wt ?4 . Retrogradation is observed to introduce a broad component to the cross-relaxation

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“…While these methods give data which is relevant to the behaviour of starch in practical applications, they have contributed relatively little to the understanding of the molecular changes that take place during gelatinization. Steady-state N M R studies have been comparatively informative in this respect [7,8,9]. Variations in the line width of starch granule suspensions with temperature have been attributed to alterations both in the state of water and the mobility of polysaccharide chains [7].…”

Section: Introductionmentioning

confidence: 99%

A Pulsed NMR Study of Some Aspects of Starch Gelatinization

Lelièvre

Mitchell

1975

Starch Stärke

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Spin‐spin relaxation times of protons in starch suspensions are reported. Values were found to change markedly upon gelatinization. This behaviour is attributed to an increase in the mobility and hydration of polymer chains. It is suggested that the change in relaxation time reflects the properties of a small number of protons in the system and that the bulk of the water is not bound in any fundamental sense.

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Broadening of the Water Proton Line in High-Resolution Nuclear Magnetic Resonance Spectra of Starch Gels

Cited by 33 publications

References 6 publications

Gel and Molecular Properties of Nonwaxy Rice Starch

Gel and Molecular Properties of Nonwaxy Rice Starch

Detection of solid-like components in starch using cross-relaxation and Fourier transform wide line proton NMR methods

A Pulsed NMR Study of Some Aspects of Starch Gelatinization

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