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Structures and properties of maltodextrins from corn, potato, and rice starches. YA-JANE WANG (1)
and LINFENG WANG (1). (1) University of Arkansas, Dept. of Food Science, Fayetteville, AR 72704.
Commercial maltodextrins derived from corn, potato, and rice starches
were characterized for their chemical structures and physicochemical properties. The chemical structures of
native and isoamylase-debranched maltodextrins were studied by high-performance liquid chromatography.
The physicochemical properties investigated included dextrose equivalent, dispersibility, dissolution,
Brookfield viscosity, bulk density, water sorption, freezing temperature, retrogradation, and maximum
freeze-concentrated glass transition. Rice maltodextrin consisted of more low molecular-weight (MW)
saccharides and potato maltodextrin consisted of more high MW saccharides. Debranched rice maltodextrin
had significantly higher content of saccharides with degree of polymerization (DP) less than 10. On the
other hand, debranched potato maltodextrin had significantly higher content of saccharides with DP greater
than 20. Rice maltodextrin had higher protein and lipid contents and exhibited very high viscosity at 40%
concentration, which might be caused by the retrograded amylose. It is believed that the longer average
chain lengths and greater retrogradation of potato maltodextrin resulted from the long amylose and
amylopectin chains of potato starch, and the shorter chains in debranched rice maltodextrin were from the
short chains in rice amylopectin. The differences in physicochemical properties of maltodextrins from
different botanical sources can be explained based on the structure differences in their parent starches.
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