Location: Healthy Processed Foods ResearchTitle: The effect of polysaccharides on the gelatinization properties of cornstarch dispersions Author
|Yokoyama, Wallace - Wally|
Submitted to: Journal of Agricultural and Food Chemistry
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/16/2011
Publication Date: 1/18/2012
Citation: Xu, Z., Zhong, F., Li, Y., Shoemaker, C., Yokoyama, W.H., Xia, W. 2012. The effect of polysaccharides on the gelatinization properties of cornstarch dispersions. Journal of Agricultural and Food Chemistry. 60(2):658-664. Interpretive Summary: Starch is widely used in processed foods to thicken or form semi-solid foods such as custards. The gelatinized starch often shrinks releasing water and has an undesirable appearance and texture. The interaction and stability of ionic and neutral polysaccharides, konjac mannon, chitosan, and carboxymethylcellulose with cornstarch despersions were studied and the optimum combinations were found to be cornstarch containing either 3% konjac glucomannan or 1-2% carboxymethylcellose.
Technical Abstract: Konjac glucomannan (neutral), CMC (negatively charged) and chitosan (positively charged) were added to cornstarch dis- persions, in order to study the effect of polysaccharide-starch interactions on the starch gelatinization properties. Pasting and retrogradation properties were measured with the rheometer and DSC. Swelling properties of the starch granules were determined by solubility index, swelling power and particle size distribution. Depending on the nature of different polysaccharides, viscosities of cornstarch dispersions were affected differently. The particle size distributions were not influenced by the addition of any of the polysaccharides. Swelling results showed that the KG and CMC molecules interacted with the released or partly released amylose in the cornstarch dispersions. This was correlated with that the short-term retrogradation of the starch pastes was retarded by the additions of KG and CMC. However, the chitosan molecules appeared not to associate with the amylose, so the retrogradation of the chitosan-cornstarch dispersions was not retarded.