Interfacial and emulsifying properties of sucrose ester in coconut milk emulsions in comparison with Tween
Interfacial and emulsifying properties of sucrose ester in coconut milk emulsions in comparison with Tween
Files (excerpt)
Published date
2013
Resource type
Publisher
ISBN
ISSN
DOI
Call no.
Other identifier(s)
Edition
Copyrighted date
Language
eng
File type
application/pdf
Extent
10 pages
Other title(s)
Advisor
Other Contributor(s)
Citation
Food Hydrocolloids. 30(2013): 358-367
Degree name
Degree level
Degree discipline
Degree department
Degree grantor
Abstract
In this study, sucrose esters were presented as a promising alternative to petrochemically synthesized
Tweens for application in coconut milk emulsions. The interfacial and emulsifier properties of sucrose
ester (SE), mainly sucrose monostearate, had been investigated in comparison with Tween 60 (TW), an
ethoxylate surfactant. The interfacial tension measurement showed that SE had a slightly better ability to
lower the interfacial tension at coconut oilewater interface. These surfactants (0.25 wt%) were applied in
coconut milk emulsions with 5 wt% fat content. The effects of changes in pH, salt concentration, and
temperature on emulsion stability were analyzed from visual appearance, optical micrograph, droplet
charges, particle size distributions, and creaming index. Oil droplets in both SE and TW coconut milk
emulsions extensively flocculated at pH 4, or around the pI of the coconut proteins. Salt addition induced
flocculation in both emulsions. The pH and salt dependence indicated polyelectrolyte nature of proteins,
suggesting that the proteins on the surface of oil droplets were not completely displaced by either added
nonionic SE or TW. TW coconut milk emulsions appeared to be thermally unstable with some coalesced
oil drops after heating and some oil layers separated on top after freeze thawing. The change in
temperature had much lesser influence on stability of SE coconut milk emulsions and, especially, it was
found that SE emulsions were remarkably stable after the freeze thawing.