• Korean Journal of Food Science and Technology
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• v.18 no.5
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• pp.393-397
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• 1986

Effects of defatting on the starch gelatinization of Akibare (Japomica) and Milyang 30(J/Indica) rice and on textural properties of cooked rices were investigated. Defatting increased amylographic viscosity greater in Milyang 30 than in Akibare. Hardness of cooked rice was decreased by defatting both in Akibare and Milyang 30. The reduction of hardness, however, was more pronounced for Milyang 30 than for Akibare, by defatting.

• Food Science and Biotechnology
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• v.18 no.2
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• pp.456-462
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• 2009

In comparison to processed wheat flour products, there is no established method for determining the water absorption of rye flour. The aim of this study was to work out a method using the Planetary mixer P 600 for the determination of water absorption (WA) and the rheological properties in rye dough made from rye flours of 4 different types (I-IV). In the correlation analysis showed that WA had positive correlation with ash, beginning of gelatinization, $125-160{\mu}m$ particles, sedimentation values at 20 and 25 min, bread yield, pH, and total titratable acidity, but had negative correlation with initial viscosity, gelatinization maximum, viscosities on swelling at 25, 28, and $31^{\circ}C$. The WA determined by the Planetary mixer P 600 agreed well with the experimental baking tests.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.2
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• pp.383-389
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• 1999

To determine the optimum condition for buckwheat noodle making, we prepared noodle from com posite flours of buckwheat, wheat and corn starch, and those physical properties and sensory evalua tion were investigated. The weights of cooked noodle became lower with increasing buckwheat content level indicating that elution of its components to soup was high. Wheat flour in the composite flours probably caused to drop gelatinization temperature and maximum viscosity compared to buck wheat flours. Corn starch in the composite flours increase gelatinization temperature and maximum viscosity compared to buckwheat flours. From the result of farinogram, buckwheat flour lower water absorption ability, and increased dough development time compared to composite flours. Adhesiveness of the cooked noodle with wheat flour was decreased. Cohesiveness of the cooked noodle was decrea sed with increasing buckwheat flour level. In sensory evaluation, chewing and softness of noodle with 100% buckwheat flour was evaluated the best. In taste, BW1 and BSW1 noodles showed slightly higher preference although there was no significant differences.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.1
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• pp.17-24
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• 1997

The effects of steeping on the physicochemical and gelatinization characteristics of glutinous rice flour and its starch were studied. Steeping conditions were 1 day at 25"C,7 days at 2iC and 7 days at 35"C. Crude protein, lipid and ash content were decreased br steeping. It was observed with scanning electron microscopy that endosperm cell wall of glutinous rice flour was diminished by steeping. Although morphology of the glutinous rice starch granules was not affected, the size was decreased by steeping. Density and water binding capacity(WBC) of glutinous rice flour and its starch were changed by steeping. X-ray diffraction pattern of glutinous rice starch was A type and was not affected by steeping. Swelling power of glutinous rice flour and its starch was increased but solubility was decreased by steeping. In Brabender amylographic examination, peak viscosity of untreated glutinous rice flour was very low and increased enormously by steeping resulting in the similar Brabender viscosity pattern to its starch. The gelatinization temperature examined by X-ray diffractometry was lowered by steeping. And the degree of gelatinization under the conclusion temperature increased with increasing of steeping Period and temperature.mperature.

• Applied Biological Chemistry
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• v.34 no.4
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• pp.379-385
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• 1991

Morphological changes of starch granules from 12 different varieties of rice were examined by scanning electron microscopy during heating at 2.5% (w/v) concentration. Rice starch granules proceeded through a similar pattern of progressive morphological changes daring heating, regardless of variety. Rice starch granules began to swell radially in the initial stage of gelatinization and then undergo radial contraction and random tangential expansion to form complex structures in the latter stage of gelatinization temperature range. At higher temperatures, starch granules softened and melted into thin flat discs, and then stretched into thin filaments to form three-dimensional networks. These progressive morphological changes were reflected in the changes of swelling power, solubility and amylograph viscosity of starch. During the transition of melting or softening, swelling power, solubility and amylograph viscosity increased rapidly. The time of loss of granular structure of starch depended on gelatinization temperature range. The ratio of amylose to amylopectin was largely responsible fur the rate of melting or softening and the fineness of a three-dimensional filamentous network above the gelatinization temperature range. Therefore, both the gelatinization temperature range and amylose content of starch affect the rate of cooking, and amylose content of starch affects the final texture of cooked starch paste.

• Food Science and Biotechnology
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• v.15 no.5
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• pp.698-703
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• 2006

We investigated how the addition of polypeptides to instant fried noodle dough affects the dough properties, starch gelatinization, and textural properties of cup-type instant fried noodles. After comparing farinograph results of 100% wheat flour with 1% wheat flour substituted with gluten, there was a small difference in the mechanical dough properties. However, in the case of 1% wheat flour substituted with gluten peptides, the dough development time increased, dough stability decreased, and weakness increased. On the other hand, when gluten or gluten peptides were added, starch gelatinization did not change significantly. At the steaming stage, substitution with gluten peptides or soybean peptides markedly changed the molecular weight distributions of extractable polypeptides. Especially in the case of wheat flour substituted with 1% gluten peptides, the relative portion of low Mw extractable polypeptides (2.5-50 kDa) decreased more compared to a control. Also, the hardness and chewiness decreased in cooked cup-type instant fried noodles containing gluten peptides. This suggests that the addition of gluten peptides can reduce the rehydration time of cup-type instant fried noodles.

• Korean journal of food and cookery science
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• v.12 no.4
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• pp.557-561
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• 1996

Physicochemical properties of nonwaxy (Dongjin byeo) and waxy (Sin-seunchal byeo) brown rice flour were investigated. The proximate composition of nonwaxy brown rice flour was 7.02% of protein, 1.14％ of ash, 3.2% of lipid and that of wfny brown rice was 7.74% of protein, 1.48% of ash,4.83% of lipid. X-ray dif- fraction patterns were A types, and relatives crystallinity of nonwaxy brown rice flour was higher than that of waxy brown rice flour. Swelling power and solubility increased with the increase of temperature, waxy brown rice flour showed higher than nonwaxy rice flour until 70$^{\circ}C$, but lower after 80$^{\circ}C$. The gelatinization temperature, breakdown and consistency of nonwaxy brown rice flour by amylogram were higher than those of the waxy brown rice flour but setback was same. The initial gelatinization temperature and the enthalpy of nonwaxy brown rice flour by DSC were higher than those of the waxy brown rice flour.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.44 no.2
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• pp.35-41
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• 2012

In this study, wheat starch adhesive was investigated the shape and structure of starch, the difference in characteristics such as chemical composition according to the fermenting period of 2 years or less. The fermenting period of wheat starch adhesive is 1 month, 2months, 4 months,6 months, 1 year, 2years old. The wheat starch adhesives were investigated total sugar contents, protein contents, properties of gelatinization, pH, the bonding strength and also observed the surface of starch,. As a result, the longer the fermenting period, the increasing in total sugar contents and decreasing in protein contents. The particle shape and surface were similar regardless of the period. In addition, properties of gelatinization according to the fermenting period also could not see the difference. In pH of the adhesive, the longer the fermenting period, the near to neutral. The adhesive was high bonding strength in 4 months, but appeared a tendency to decrease from 6 months. The damage assessment through the UV degradation in regard to the papers applied the adhesive was accomplished. Color difference was no change except 1 month. The 4 months and 6 months' pH was each 5.0, 5.2. But it was near to neutral that the 12 months and 24 months' pH was each 5.7, 5.9.

• Korean Journal of Food Science and Technology
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• v.31 no.4
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• pp.999-1004
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• 1999

Physicochemical properties of the native chestnut starch(NCS) and hydroxypropylated chestnut starch(HCS) with propylene oxide were investigated. The water binding capacity and blue value of chestnut starch were increased by hydroxypropylation. With increasing temperature, the swelling power and solubility were increased and those of HCS were higher. The light transmittance of HCS was higher than it of NCS. Endotherm characteristics were studied with DSC showed that temperatures of initial gelatinization of NCS and HCS were $64.44^{\circ}C$ and $62.80^{\circ}C$, respectively. The temperature of initial gelatinization and enthalpies gelatinization in chestnut starch were decreased by hydroxypropylation. And the viscosity of HCS was higher than that of NCS.

• Korean journal of food and cookery science
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• v.25 no.5
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• pp.586-592
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• 2009

Sulgidduk samples containing 2, 4, and 8% red ginseng powder and a control[ED highlight - consider specifying what the control was, if 0%, then change to Sulgidduk samples containing 0(control), 2, 4 and 8%] were examined for moisture content, color, gelatinization properties, textural characteristics, and sensory qualities to determine the optimal ratio of red ginseng powder in the formulation. The moisture contents among the samples did not differ significantly. Specifically, they ranged from 39.64 to 40.69%, and increased as the red ginseng powder content increased. Additionally, the lightness decreased and the yellowness and redness increased as the red ginseng powder content increased. Evaluation of the gelatinization properties revealed that the, peak viscosity(P), hold viscosity(H), final viscosity(F), setback, and time to peak viscosity decreased with increasing red ginseng powder content, but the breakdown and temperature to peak viscosity did not differ significantly among samples[ED highlight - please ensure my changes are correct]. The hardness and adhesiveness decreased with increasing red ginseng powder content, as did the cohesiveness, gumminess, and chewiness; however, the springiness did not differ significantly among samples. Sulgidduk containing 4% red ginseng received the highest scores for flavor, taste, texture and overallquality. Based on the above results of the sensory and texture analyses, Sulgidduk containing 4% red ginseng had the highest quality[ED highlight - please ensure my changes are correct].