scholarly journals Water Behavior of Aerogels Obtained from Chemically Modified Potato Starches during Hydration

Foods ◽  
2021 ◽  
Vol 10 (11) ◽  
pp. 2724
Author(s):  
Joanna Le Thanh-Blicharz ◽  
Jacek Lewandowicz ◽  
Zuzanna Małyszek ◽  
Przemysław Łukasz Kowalczewski ◽  
Katarzyna Walkowiak ◽  
...  
Keyword(s):  
Chemical Modification ◽  
Water Activity ◽  
Potato Starch ◽  
Three Dimensional ◽  
Lattice Relaxation ◽  
Lattice Relaxation Time ◽  
Spin Lattice Relaxation ◽  
Dimensional Structure ◽  
Chemically Modified ◽  
Potato Starches

Aerogels are highly porous materials that are prepared by removing water held within a hydrogel in a manner that maintains the three-dimensional structure of the gel. Recently, there has been much interest in the preparation of aerogels from biopolymers, including starch. The applicability of native starches in the food industry is partially limited; therefore, the functional properties of starch are often improved by means of physical and/or chemical modification. The aim of the work was the analysis of molecular dynamics and the transport of water in aerogels obtained from native and chemically modified potato starches of the normal and waxy variety. Chemical modification with OSA (E 1450) as well as cross-linking with adipic anhydrite and acetylation (E 1422) had no significant impact on the hydration of potato starch aerogels as well as equilibrium water activity. The introduction of chemical moieties into starch macromolecules led to the improved binding of water by the biopolymer matrix; this was especially evident in the case of waxy starch derivatives. A increase in the amylopectin-to-amylose ratio of starch used for production of aerogels resulted in a decrease of equilibrium water activity along with spin-lattice relaxation time.

scholarly journals Effect of enzymatic modification on frozen chicken surimi

2013 ◽  
Vol 31 (No. 3) ◽  
pp. 203-210 ◽  
Author(s):  
J. Stangierski ◽  
R. Rezler ◽  
H.M. Baranowska ◽  
S. Poliszko
Keyword(s):  
Water Activity ◽  
Considerable Increase ◽  
Control Sample ◽  
Lattice Relaxation ◽  
Lattice Relaxation Time ◽  
Spin Lattice Relaxation ◽  
Poultry Meat ◽  
Spin Lattice ◽  
Fresh Frozen ◽  
Texture Attributes

The effects were assessed of the addition of microbial origin transglutaminase (MTG) and modification time of proteins in frozen chicken surimi on its texture, rheological attributes, molecular dynamics of water, water activity, and thermal properties of proteins. Surimi was produced from mechanically separated poultry meat. The amount of 3 g/kg MTG were added to samples of fresh, frozen (stored at –22°C for 30 days), and defrosted surimi which were incubated for a max. 9 h at 15°C. The highest values of the analysed texture attributes and rheological modules were recorded in the case of the sample enzymatically modified before freezing. The values of spin-lattice relaxation time were significantly higher in the control system. In comparison to non-modified surimi, the samples treated with MTG were characterised by a considerable increase in the equilibrium water activity. After 7 h modification, the value of enthalpy for surimi protein was by approx. 30% lower in comparison to the control sample.  

Crystal Structure and Cationic Motion of o-Toluidinium Chloranilate and m-Toluidinium Chloranilate Studied by X-ray Diffraction and 1H NMR

2003 ◽  
Vol 58 (11) ◽  
pp. 631-637 ◽  
Author(s):  
Takeo Fukunaga ◽  
Naoki Kumagae ◽  
Hiroyuki Ishida
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bonds ◽  
Three Dimensional ◽  
Lattice Relaxation ◽  
Lattice Relaxation Time ◽  
Spin Lattice Relaxation ◽  
Molecular Orbital Calculations ◽  
X Ray Diffraction ◽  
X Ray ◽  
Spin Lattice

The crystal structure of o-toluidinium chloranilate and m-toluidinium chloranilate, 2CH3C6H4-NH3+ · C6O4Cl22−, was determined by single crystal X-ray diffraction at room temperature. It was found that o-toluidinium chloranilate (I) is monoclinic, P21/n (#14), Z = 2, a = 5.2184(14), b = 7.825(2), c = 22.840(5) Å , and β = 92.015(19)°, and m-toluidinium chloranilate (II) is monoclinic, P21/c (#14), Z = 2, a = 11.214(2), b = 5.4844(10), c = 16.379(6) Å, and β = 105.21(2)°. In these salts, the cations are connected with the anions by N-H... O hydrogen bonds to form 2:1 units of 2CH3C6H4NH3+ · C6O4Cl22− that are located on inversion centers. The 2CH3C6H4NH3+ · C6O4Cl22− units in both salts are connected by other N-H... O hydrogen bonds to build a three-dimensional hydrogen-bond network. Motions of the toluidinium ions in solid (I) and (II) were studied by 1H NMR spin-lattice relaxation time measurements. Reorientations of the NH3+ group about the C-N bond axis and the CH3 group about the C-C bond axis were observed, and their motional parameters were evaluated. The internal rotational barriers of the NH3+ and CH3 groups of an isolated o-toluidinium ion were estimated from ab initio molecular orbital calculations at HF/6-31G(d,p), MP2/6-31G(d,p), and B3LYP/6-31G(d,p) levels of theory.

NUCLEAR SPIN-LATTICE RELAXATION TIME IN TIN

1978 ◽  
Vol 39 (C6) ◽  
pp. C6-1215-C6-1216
Author(s):  
H. Ahola ◽  
G.J. Ehnholm ◽  
S.T. Islander ◽  
B. Rantala
Keyword(s):  
Relaxation Time ◽  
Nuclear Spin ◽  
Lattice Relaxation ◽  
Lattice Relaxation Time ◽  
Spin Lattice Relaxation ◽  
Spin Lattice Relaxation Time ◽  
Spin Lattice ◽  
Nuclear Spin Lattice Relaxation

Protron spin-lattice relaxation time of duchenne dystrophy skeletal muscle by magnetic resonance imaging

1988 ◽  
Vol 11 (2) ◽  
pp. 97-102 ◽  
Author(s):  
Kiichiro Matsumura ◽  
Imaharu Nakano ◽  
Nobuo Fukuda ◽  
Hiroo Ikehira ◽  
Yukio Tateno ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Skeletal Muscle ◽  
Relaxation Time ◽  
Magnetic Resonance ◽  
Lattice Relaxation ◽  
Lattice Relaxation Time ◽  
Spin Lattice Relaxation ◽  
Resonance Imaging ◽  
Duchenne Dystrophy ◽  
Spin Lattice

Determination of chemical shift anisotropy tensor and molecular correlation time of proton pump inhibitor omeprazole by solid state NMR measurements

2020 ◽  
Vol 44 (44) ◽  
pp. 19393-19403
Author(s):  
Krishna Kishor Dey ◽  
Manasi Ghosh
Keyword(s):  
Correlation Time ◽  
Chemical Shift Anisotropy ◽  
Lattice Relaxation ◽  
Lattice Relaxation Time ◽  
Spin Lattice Relaxation ◽  
Spin Lattice ◽  
Structure And Dynamics ◽  
Molecular Correlation ◽  
Anisotropy Tensor

The correlation between the structure and dynamics of omeprazole is portrayed by extracting CSA parameters through the 13C 2DPASS CP-MAS SSNMR experiment, site specific spin–lattice relaxation time by Torchia CP experiment, and calculation of the molecular correlation time.

scholarly journals Tunneling Spectroscopy by Nuclear Magnetic Resonance: Analysis of Rotational Tunneling in Solid Pentamethylbenzene

1985 ◽  
Vol 40 (11) ◽  
pp. 1075-1084
Author(s):  
W. T. Sobol ◽  
K.R. Sridharan ◽  
I. G. Cameron ◽  
M. M. Pintar
Keyword(s):  
Frequency Dependence ◽  
Lattice Relaxation ◽  
Time Correlation ◽  
Lattice Relaxation Time ◽  
Polarization Transfer ◽  
Spin Lattice Relaxation ◽  
Transfer Model ◽  
Nuclear Magnetic Resonance Analysis ◽  
Spin Lattice ◽  
Resonance Analysis

The frequency dependence of the spin-lattice relaxation time T1 was measured at three temperatures near one of the Zeeman-tunneling level matching resonances for pentamethylbenzene. These measurements are correlated with 71 temperature dependence data from the literature. It is shown that the frequency dependence of the Zeeman-torsion coupling time cannot be explained in terms of the semiclassical perturbation theory using time correlation functions. A three bath polarization transfer model is also employed and the applicability of both models discussed. Zeeman-torsion coupling is further investigated using a saturation sequence and the results are compared with the predictions of the three bath polarization transfer model.

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