Exploring the new applications of gum arabic obtained from Acacia species to preserve fresh fruits and vegetables.

摘要

Gum arabic is an exudate from the stems and branches of sub-Saharan Acacia Senegal and Acacia seyal trees that either naturally exude sap or are tapped to form large nodules of gum to seal wounds in the bark of the tree. It is a complex and variable mixture of arabinogalactan oligosaccharides, polysaccharides and glycoproteins. It is a neutral or slightly acidic salt of a complex polysaccharide and can be readily dissolved in hot or cold water. It is the least viscous and the most soluble of the hydrocolloids. Therefore, it is the most extensively used hydrocolloid in the industrial sector because of its emulsification, film forming and encapsulation properties. More than one half of the world's supply is used in confections, where the gum acts to retard sugar crystallisation, and to thicken candies, jellies, glazes and chewing gums. The flavour industry uses the gum arabic as a flavour-fixative, protecting the flavour from evaporation, oxidation, and absorption of moisture from air. It is also used as a foam stabiliser and agent to promote adhesion of foam to glass. However, in the present study the potential of gum arabic was evaluated as an edible coating material for the preservation of fresh fruits and vegetables during cold storage.