| In this study, the emulsifying and foaming properties of a novel exudate gum from
Dorema ammoniacum (AMG) were assessed in comparison with the well-known gum
Arabic from Acacia tree (GAC). The sunflower oil-based emulsion (10% v/v) containing
various concentrations (5%–15% w/v) of AMG and GAC was prepared. At all concentrations,
AMG showed higher surface and interface activity than GAC. Increasing
in AMG and GAC concentrations caused to increase and decrease in Z average, respectively.
Overall, the GAC-stabilized emulsion showed lower Z average and PDI
value than the AMG-stabilized emulsion during storage time. The sample containing
AMG showed higher emulsion capacity and lower emulsion stability in comparison
with the one containing GAC at all concentrations. The storage stability decreased
and increased with increasing in AMG and GAC concentrations, respectively. After
two-week storage, the emulsions containing 10 and 15% AMG showed higher phase
separation than those containing GAC; however, this was opposite about sample
containing 5% AMG. At thermal, centrifuge, and freezing conditions, the emulsion
containing 5% AMG indicated significantly higher stability than GAC samples; however,
at higher concentration, opposite effect could be observed. The foaming capacity
of the samples containing AMG increased from 81% to 93% by increasing gum
concentration from 5% to 15%. The solutions containing AMG showed higher foam
capacity than control samples (without gum) and those containing GAC at all concentrations.
Increasing in AMG and GAC concentrations slightly improved foam stability,
and the highest value (92%) belonged to 15% AMG solution. |