In:
Die Angewandte Makromolekulare Chemie, Wiley, Vol. 64, No. 1 ( 1977-09-26), p. 133-146
Abstract:
On vibration grinding of air‐dried pectin preparations with a hydrolytic cleavage of the α(1←4) glycosidic linkage the degree of esterification remains constant. The random distribution of free and of esterified carboxyl groups remains unchanged. The affinity of the carboxyl groups to Ca 2+ ions is changing only when oligomers are formed. The limit of a significant weakening of the ionic linkage being dependent on the chain lenght, will be shifted to higher viscosity numbers and to higher degrees of polymerization, respectively, with an increasing degree of esterification. Moreover, at a proceeding mechanolysis there is a characteristic decrease of the width of the distribution of molecular weights. This could be proved by gel chromatography. An enrichment of the neutral saccharides still present in the pectin preparations together with the D‐galacturonic acid in spite of an intense purification, takes place independently of the grinding time and of the degree of degradation, respectively, as well in the low‐molecular as in the high‐molecular fractions of the gel chromatograms.
Type of Medium:
Online Resource
ISSN:
0003-3146
,
1522-9505
DOI:
10.1002/apmc.05.v64:1
DOI:
10.1002/apmc.1977.050640112
Language:
English
Publisher:
Wiley
Publication Date:
1977
detail.hit.zdb_id:
280091-3
detail.hit.zdb_id:
1480834-1
