|QIU, SHUANG - China Agricultural University|
|TATSUMI, EIZO - Japanese International Research Center For Agricultural Sciences (JIRCAS) - Japan|
|YIN, LIJUN - China Agricultural University|
Submitted to: Food Hydrocolloids
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/30/2015
Publication Date: 2/19/2015
Publication URL: http://handle.nal.usda.gov/10113/62224
Citation: Qiu, S., Yadav, M.P., Tatsumi, E., Yin, L. 2015. Effects of corn fiber gum with different molecular weights on the gelatinization behaviors of corn and wheat starch. Food Hydrocolloids Journal. 53:180-186.
Interpretive Summary: Corn fiber is a byproduct from US corn milling industries. It is an abundant low value material used for animal feed. Corn fiber gum (CFG) is prepared from corn fiber by using an alkaline water extraction. We reported earlier that the addition of CFG to starch improves its texture. Now we report the effect of different sizes of CFG on the gelatinization and amylose leaching behavior of starch. CFG is a natural dietary fiber and its addition to starch increases its nutritional value and it also may help prevent colon cancer. It was found that adding larger CFG prevents amylose leaching during cooking. The large size CFG molecules may protect starch granules more effectively and may make the final food products more appealing to consumers. Many processed foods contain some kind of thickener, stabilizer and gelling agent and this CFG composite with starch has a potential to be used for these applications. Viscosity is one of the most widely used properties in food applications. In this respect, these CFG composite can be used in foods where oil or fat content has to be reduced. CFG has a great effect on the viscosity of other carbohydrate polymers, so its mixture with starch can control the viscosity of the food system, which in turn helps to replace fat or oil in the final products. Such properties may also enable it to be used as a low calorie replacement for carbohydrate additives used as thickeners, flavor carriers and suspension stabilizers in a wide variety of food products. These findings will benefit U. S. corn processors by adding value and creating additional markets for their by-products. It will also benefit U. S. manufacturers of CFG who will be able to produce a constant supply of very superior thickeners at reasonable prices. The generation and recovery of additional valuable products from corn milling by-products will also indirectly help to reduce overall cost of fuel ethanol produced from corn kernels.
Technical Abstract: Corn fiber gum (CFG) is a novel arabinoxylan hydrocolloid. Recent research has shown that it has a considerable potential in food processing. In our previous study, we reported that CFG could be used to modify the gelling and rheological properties of starch-based food. In this study, starch and CFG with several molecular characteristics composite systems were evaluated. The pasting and thermal properties, microstructure and leached amylose of maize and wheat starch have been studied. CFG addition showed lowering of peak viscosity and breakdown, increase of final viscosity of maize starch, and increase of breakdown of wheat starch. The changes in RVA characteristics were more pronounced as the Mw of CFG was increased. The amount of leached amylose of maize/wheat starch gels was lower as the higher Mw CFG was used. The thermal characteristics of maize starch/CFG mixtures varied insignificantly as determined in DSC heating process. Confocal laser scanning microscopy (CLSM) confirmed changes in gels microstructure as starch components tended to be inhibited from leaching out of the granules, and the morphology of wheat starch granule was well-defined when CFG was added.