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Möglichkeiten und Grenzen der Kernresonanz‐lmpuls‐Spektroskopie in der Anwendung auf Probleme der Stärkeforschung und Stärketechnologie
Author(s) -
Lechert H.
Publication year - 1976
Publication title -
starch ‐ stärke
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.62
H-Index - 82
eISSN - 1521-379X
pISSN - 0038-9056
DOI - 10.1002/star.19760281102
Subject(s) - starch , swelling , deuterium , proton , materials science , potato starch , magnetization , relaxation (psychology) , molecule , chemistry , nuclear magnetic resonance , analytical chemistry (journal) , physics , organic chemistry , composite material , psychology , social psychology , quantum mechanics , magnetic field
Possibilities and Limits of Pulsed NMR Spectroscopy for the Investigation of Problems of Starch‐Research and Starch Technology . The time behaviour of nuclear magnetization influenced by HF‐pulses is characterized mostly by the socalled relaxation times which give information on molecular mobility. The proton signals of starch show beside the signals of the starch framework for different water contents and temperature three kinds of water, the relative portions of which can be taken from details of the time functions of the magnetization. The molecules with the lowest mobility belong to the crystal structure of the starch. With increasing mobility the socalled capillary water and at high water contents molecules with very good mobility occur, which are connected with the appearance of a heat of melting. Changing the water‐ and OH‐protons of the starch against deuterons, the swelling process can be studied by proton resonance experiments on the unexchangable CH‐protons of the starch, carrying out the swelling in D 2 O. Further, details of retrogradation and freeze thaw phenomena can be studied by this method.