Gelatinization Properties Of Potato Starch Research Articles

Effects of Lycium barbarum polysaccharide on gelatinization properties of potato starch

AbstractIn this research, the influences of Lycium barbarum polysaccharide (LBP) on gelatinization properties of potato starch (POS) were evaluated. The swelling power of POS was inhibited, and the leaching of amylose declined. The LBP increased the peak temperature (Tp), while decreased the enthalpy (ΔH) of gel from 6.62 to 4.87 J g−1. Compared with pure POS gel, the hardness of POS gel added with 0.6% LBP decreased by 13% after storage for 20 days. The syneresis of gels that exposed to four freeze–thaw cycles was significantly reduced from 65.8% to 41.2%. Rheological measurements revealed that the viscoelasticity of composites was enhanced. The addition of LBP can enlarge the particle size of composite gels, and make the microstructure of composite gels become smooth, compact, and thicker pore wall. Fourier‐transform infrared spectroscopy (FTIR) and interaction force test showed that the hydrophobic bond was likely to be the main force.Practical applicationsThe incorporation of LBP could improve the gelling characteristics of POS‐based gel by delaying the change on gel hardness of POS composites during storage, and reducing the undesirable impact of freeze‐thawing treatment on POS gel system. The research outcome of the gelling characteristics of POS‐based gel can be used for frozen food, low‐temperature refrigerated food, and soft food. And the results of rheological behavior on POS‐based gel can be used in sauces, thickeners, and puddings.

Bacterial Cellulose-Based Biomimetic Nanofibrous Scaffold with Muscle Cells for Hollow Organ Tissue Engineering.

In this study, we built a bilayer nanofibrous material by utilizing the gelatinization properties of potato starch (PS) to interrupt bacterial cellulose (BC) assembly during static culture to create more free spaces within the fibrous network. Then, muscle cells were cultured on the loose surface of the BC/PS scaffolds to build biomaterials for hollow organ reconstruction. Our results showed that the BC/PS scaffolds exhibited similar mechanical characters to those in the traditional BC scaffolds. And the pore sizes and porosities of BC/PS scaffolds could be controlled by adjusting the starch content. The average nanofiber diameters of unmodified BC and BC/PS composites is approximately to that of the urethral acellular matrix. Those scaffolds permit the muscle cells infiltration into the loose layer and the BC/PS membranes with muscle cells could enhance wound healing in vivo and vitro. Our study suggested that the use of bilayer BC/PS nanofibrous scaffolds may lead to improved vessel formation. BC/PS nanofibrous scaffolds with muscle cells enhanced the repair in dog urethral defect models, resulting in patent urethra. Improved organized muscle bundles and epithelial layer were observed in animals treated with BC/PS scaffold seeded by muscle cells compared with those treated with pure BC/PS scaffold. This study suggests that this biomaterial could be suitable for tissue engineered urinary tract reconstruction and this type of composite scaffold could be used for numerous other types of hollow organ tissue engineering grafts, including vascular, bladder, ureter, esophagus, and intestine.

でんぷん粒のアニーリング 温水処理と湿熱処理

This review deals with two kinds of physical modifications of starch which have been socalled “warm water treatment” and “heat-moisture treatment.”A temperature-composition diagram illustrating the gelatinization and the melt of starch granules has been constructed from the DSC data that show two kinds of endothermic transitions for the starch-water system. The diagram obtained corresponds to that of the crystalline polymerpoor solvent (diluent) system. Thermal phase transitions of the starch-water system have been discussed using the diagram.The effect of warm water treatment on starch granules has been studied: This treatment causes the sharpening and the rise of the gelatinization temperature range, and the reduction of the swelling power and the solubility. The structural changes in granules during the treatment have been interpreted in terms of the annealing of semicrystallites of starch molecules. In fact, photomicrographs presented in the paper well shows the annealing process of starch granules with increasing temperature. It was concluded that this treatment brings about increases in homogeneity of both individuals and populations of starch granules through the process of annealing of starch crystallites.Heat-moisture treatment brings about changes in the physical properties of starch through the process of the “melting” of starch granules. In the case of potato starch, the “B” pattern of X-ray diffraction is changed to “A” or “C” pattern, involving increases in heterogeneity of granular structure. The gelatinization properties of potato starches treated at various moisture levels and temperatures were examined and the relationships between the treatment conditions and the gelatinization properties have been clarified. From the results, it was concluded that heat-moisture treatment brings about irreversible disordering of granular structures with increasing of associative forces among starch molecules in granules.Degradation of the physically modified starches with amylases and mineral acids were also studied. Susceptibility of heat-moisture treated potato starches to amylases was much larger than that of untreated one, but not in the case of corn starch. Microscopic observations by SEM showed that the degradation of the treated potato starch with glucoamylase from R. niveus and α-amylase (liquefying type) from B. subtilis (BLA) proceeded in the different mode each other. Differences in the action mode of BLA on the digestion of corn and the treated potato starch were also shown. In contrast to the heat-moisture treated potato starch, the warm water treated potato starch showed less susceptibility to amylases than the untreated one did. Some scanning electron micrographs of acid-modified potato starch granules were also presented.In conclusion, the possibilities of the utilization of the physically modified starches were described.

On the Possibility of Modifying the Gelatinization Properties of Starch by Lipid Surface Coating

AbstractThe gelatinization properties of potato starch were modified by coating the surface of the starch granules with lipids by an aqueous dispersion of monoglyceride or an ethanol monoglyceride solution. The volumes of gels were smaller than those of the untreated starch. In the polarizing microscope it was observed that decreased disruption of starch granules in connection with gelatinization occurs with increasing amount of lipids present on the surface. The gelatinization enthalpy and the gelatinization temperature at a low water content measured by DSC (Differential Scanning Calorimetry) were not influenced by the lipid coating. A third endothermic transition, however, was observed for the lipid‐coated starch. Freeze‐drying, used in the preparation of the lipid‐coated starch, was found to lower the gelatinization enthalpy as well as the gelatinization temperature.