Gum arabic was exposed to varying degrees of ionising gamma irradiation. The result confirms the lability of certain sugar and amino acid residues in the gum structure. A chemical deproteination was carried out on a gum arabic solution using butan-1-o1, and confirms previous results which indicate that the protein content of gum arabic cannot be totally isolated from the polysaccharide structure. Mild sequential Smith degradations were carried out on gum arabic, these degradations were less structurally destructive than previous periodate oxidations. Gum arabic was also fractionated by its ability to emulsify limonene oil and associate with its molecular surface. All the previous degradative studies give valuable structural information to elucidate the gum's heterogeneous branched nature. An analytical study was carried out on ten gum arabic samples of Sudanese and Nigerian origin, collected between 1950-1989. The gum's polysaccharide and amino acid composition were fully characterised and their emulsification stability determined. There are convincing indications that gum arabic has remained remarkably constant in chemical nature over the past 40 years. Seven gum exudates of the genus Albizia, four Acacia gum exudates and six Combretum gum exudates, all of which are not permitted as food additives, were analysed for their polysaccharide and amino acid composition. Food manufacturers require analytical data to characterise non-permitted gums to prevent their use as adulterants to substitute for gum arabic.
Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:659621 |
Date | January 1993 |
Creators | Morrison, N. A. |
Publisher | University of Edinburgh |
Source Sets | Ethos UK |
Detected Language | English |
Type | Electronic Thesis or Dissertation |
Source | http://hdl.handle.net/1842/12693 |
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