| Summary: | A series of propionylated starches with diff erent degrees of substitution (DS) was synthesised
and their physicochemical properties and application as a stabiliser were investigated.
Starch propionates with moderate DS were prepared by esterifi cation of native corn
starch with propionic anhydride. By varying the reaction times of the esterifi cation process,
twelve starch propionates with DS of 0.47 to 0.94 were prepared. FTIR and NMR confi
rmed the introduction of propionyl groups to the starch. X-ray diff raction patt ern showed
reduced crystallinity in the starch propionates. The contact angle was found to increase
proportionately with the increase in DS. Swelling power results showed that starch propionates
were able to swell more than native corn starch at low temperature (40 °C). Oil-in-
-water (O/W) emulsions prepared using starch propionates (DS of 0.64 to 0.86) showed exceptional
stability when challenged by centrifugation stress test. These stable O/W
emulsions had viscosities in the range of 1236.7–3330.0 mPa·s. In conclusion, moderately
substituted short-chain (propionylated) starches could be a promising cold swelling starch,
thickener and O/W emulsion stabiliser in food, pharmaceutical and cosmetic industries.
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