• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.45 no.4
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• pp.1-8
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• 2013

High loading of printing and writing grades with fillers has many advantageous aspects in papermaking because it allows decreasing fiber use and reducing manufacturing cost. High loading technology, however, has some disadvantageous aspects as well. It decreases physical properties of papers, especially strength properties. The problem associated with high loading can be reduced by applying surface sizing starch solution onto paper surface. It is important to control the penetration of the surface sizing starch solution into paper web to obtain the desired property improvement. In this study, the effect of the addition of two polymers into starch solution on paper properties has been examined. PVOH and polyDADMAC were used as polymeric additives for surface sizing with oxidized starch. Viscosity of starch solutions and surface roughness of dried starch films on glass slides showed that some interactions between polymeric additives and oxidized starch have been occurred and the most extensive interaction with starch solution was obtained with high molecular weight polyDADMAC. Low molecular weight PVOH was most effective in improving folding endurance and internal bond strength. On the other hand, polymer addition showed no effect on surface strength of paper. This indicates that not the level of starch holdout but the bonding strength of starch itself has predominant influence on surface strength of paper.

• Preventive Nutrition and Food Science
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• v.11 no.2
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• pp.146-154
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• 2006

Structural modification of corn starch by gamma irradiation was evaluated for under dry conditions at varied intensities from 0 to 40 kGy. Under scanning electron microscopy, the granule shape of corn starch was not significantly affected by the irradiation up to 40 kGy. In addition, X-ray diffraction and melting patterns of the irradiated starches were similar to those of the native starch, indicating that crystalline regions in the starch granules were not changed by irradiation. However, the pattern of gel permeation column chromatography showed a significant increase in partial hydrolysis of gamma irradiated starch samples. The degree of polymerization and the paste viscosity of irradiated starch samples dose-dependently decreased significantly with irradiation, and increased solubility and clarity were observed in the irradiated starch solution. In addition, the degree of retrogradation decreased as irradiation dose increased. Irradiation of corn starch has advantages over the ordinary acid or the enzyme hydrolysis modification methods. It does not affect the granular shape and crystalline phase of starch during hydrolysis, and the process can be carried out in dry state.

• The Korean Journal of Community Living Science
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• v.23 no.3
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• pp.233-243
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• 2012

This study was performed to determine the quality characteristics of Jeungpyun with added modified starch. The addition of modified starch did not change the pH level of the samples, but it did increase the volume. The b-value of Jeungpyun with 3% modified starch was significantly lower than that of the control group. The addition of 3% modified starch also significantly increased the hardness, adhesiveness, gumminess and chewiness of the experimental group over the control group. In the test of sensory characteristics, the cell size of Jeungpyun with 2 and 3% modified starch was larger than that of the control group. Cell uniformity of Jeungpyun with 2% modified starch was lower than that of the control group. The hardness of Jeungpyun with modified starch was significantly higher than that of the control group. In the test of taste preference, Jeungpyun with modified starch beat the control group substantially. The quality of Jeungpyun with 1 and 3% modified starch showed a higher overall score than that of the control group.

• Korean Journal of Food Science and Technology
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• v.29 no.4
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• pp.693-699
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• 1997

The effects of mugwort juice on the gel properties of corn starch (CS), mung bean starch (MS), and potato starch (PS) were investigated. Water holding capacities of three starches were increased with addition of the juice. Solubilities of CS and MS were also increased. Swelling power was increased in CS but decreased in MS. Viscoamylogram showed that 5% addition of the juice lowered the initial gelatinization temperatures of CS and MS, but raised the temperature of PS. While peak viscosities of CS and MS pastes were decreased a little, the viscosity of PS paste was decreased remarkably from 2,280 BU to 845 BU. Addition of mugwort juice did not affect significantly the hardness of starch gels during 7 days of storage at $25^{\circ}C\;and\;4^{\circ}C$. Degrees of gelatinization of the starch gels were affected by addition of the juice, especially in PS, during storage. Freeze-thaw stabilities of three gels were not changed by addition of the juice. The starch gels added with the mugwort juice had smooth surface visually because the crude fibrous materials of mugwort were removed during juice preparation.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2006.06b
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• pp.245-250
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• 2006

This study was focused on the use of cationic PAM (Polyacrylamide) as a surface sizing additive to improve the surface sizing properties of paper. Effects of the ionic property, viscosity and charge density of PAM on bending stiffness of surface sized papers were investigated. Use of cationic PAM as a surface sizing additive improved bending stiffness while addition of anionic PAM did not show any effect. Increase of starch holdout with the addition of cationic PAM was attributed as a prime reason of stiffness increase. Viscosity of PAM was one of the most important factors affecting surface sizing due to its influence on the interaction between cationic PAM and oxidized starch solution. Greater improvement of bending stiffness of paper was obtained when high charged PAM was used as an additive. The order of addition was found to have significant influence on the effect of additives since it influences the formation of network structure among starch, cationic PAM, and SA (styrene acrylic acid copolymer). Investigation on the penetration of starch solution was carried out with CLSM (Confocal Laser Scanning Microscopy), and it was shown that the addition of cationic PAM to oxidized starch solution made starch molecules stay on the paper surface rather than penetrating into the paper structure because of the electrostatic interaction between negatively charged fibers and positively charged cationic PAM.

• The Korean Journal of Food And Nutrition
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• v.13 no.5
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• pp.403-410
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• 2000

This study was carried out to understand the effect of addition of potato search on the frozen dough. The characteristics of frozen dough were measured by the farinogram, the extensogram and the amylogram. The results of these measurements show that the dough added with starch has higher stability than the control. The physical and chemical change of the dough were measured in accordance with the period of the frozen storage. The dough added with starch showed smaller physical and chemical change than control, which means that the starch prevents the frozen dough from the deterioration during the frozen storage. It is supposed from this result that the starch protects the activity of yeast and the structure of gluten matrices from frozen damage. It is understood from this study that addition of potato starch into frozen dough improve the stability of the frozen dough.

• Journal of the Korean Society of Food Science and Nutrition
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• v.27 no.5
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• pp.897-902
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• 1998

This study was conducted to develop the standard recipe of Dopyun according to the various content of mung bean starch and sugar. The effects of mung bean starch(10%, 15%, 20%) and sugar(20%, 30%) were evaluated on textural and sensory properties of Dopyun through the mechanical properties using texture analizer and sensory evaluation. Color was tested by color and color difference meter. For sensory evaluation, higher content of sugar and lower content of mung been starch(sugar 30%, mungbean starch 10%) showed advantages in acceptance fo taste and overall quality. Mechanical properties of hardness, cohesiveness and chewiness of Dopyun were increased significantly in Dopyun with higher content of mung bean starch and sugar. The values of Hunter color system indicated that "L" and "b" values tended to decrease and "a" value increase, as the mung bean starch and sugar proportion increased. In the analysis of correlation between sensory evaluation and acceptance test, it was found that they were highly related. In view of the above results, it came to the conclusion that Dopyun with the addition of 30% sugar and 10% mung bean starch could give the best result among the groups studied.sult among the groups studied.

• Korean Journal of Food Science and Technology
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• v.52 no.4
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• pp.423-426
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• 2020

This study was performed to investigate how the addition of starch nanoparticles prior to whipping could affect the quality characteristics and stability of full-fat dairy cream. Starch nanoparticles were prepared by dry heating under mildly acidic conditions and added to dairy cream as amount of 1, 3, and 5% (w/w). The whipped cream's storage stability, viscosity, overrun, and droplet size were investigated in combination with various starch nanoparticle contents. The storage stability and apparent viscosity increased in parallel with the increasing starch nanoparticle content compared to the control. The mean size and homogeneity of the droplets in the whipped cream increased with higher starch nanoparticle addition levels. Even though the whipped cream overrun was reduced by the addition of starch nanoparticles, the 1% addition level exhibited a similar overrun value as the control.

• Journal of the Korean Wood Science and Technology
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• v.42 no.4
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• pp.376-384
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• 2014

This study investigated the effect of nanocellulose, such as microfibrillated cellulose (MFC) and cellulose nanocrystal (CNC), and aminated starch on tensile property and thermal stability of plasticized starch film. Glycerol (23 wt%) was used as a plasticizer and nanocelluloses of 1-30 parts per hundred parts of resin (phr) in the basis of plasticized starch were added. Tensile strength and elastic modulus increased with increasing nanocellulose addition amount, whereas elongation at break decreased. Tensile properties of MFC-reinforced starch film were higher than those of CNC-reinforced film. Optimum addition amount of aminated starch, which is commonly used for paper sizing, to improve tensile property of film, was found to be 5%. And 1% addition of aminated starch showed the best effect in the improvement of tensile property of the film. Thermal stability was improved with the addition of MFC to plasticized starch film with and without aminated starch.

• Food Science and Biotechnology
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• v.15 no.6
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• pp.986-989
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• 2006

Sweet potato starch noodles prepared without freezing exhibited higher cooking loss and water uptake during cooking and usually resulted in noodles with a softer and stickier texture compared to commercial sweet potato starch noodles manufactured using a freezing process. By utilizing the starches of different plant sources (potato, cowpea, and sago in an equivalent mixture with sweet potato starch), however, the cooking properties and texture of the starch noodles could be improved. Among the starches tested, cowpea starch was most effective in providing cooking and textural properties similar to those of commercial noodles. As an alternative approach, the addition of a minor amount (0.1 % based on total solid weight) of various gums (xanthan, gellan, locust bean gum, curdlan, and carboxymethyl cellulose) was also examined. The addition of curdlan to noodles was effective in increasing the gumminess and hardness, and reducing the stickiness of noodles. Utilizing different starches and gums can improve the overall texture and quality of sweet potato starch noodles produced without freezing.