• KOREAN JOURNAL OF CROP SCIENCE
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• v.68 no.2
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• pp.35-46
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• 2023

The transplanting period limit considering the rice yield in the Dague region, the inland plains of Gyeongsangbuk-do, was estimated to be July 15^th for early and mid-maturing rice and July 5^th for mid-late maturing rice. However, as the transplanting time was delayed, the characteristics of rice starch changed significantly. In the case of early and mid-maturing rice varieties, the starch granule size increased as the transplanting time was delayed; the opposite tendency was observed for mid-late maturing varieties. In all mature rice types, the late transplanting resulted in a longer pasting time and a higher pasting temperature. In addition, the peak viscosity, breakdown, and gelatinization temperature were significantly lowered, the relative crystallinity degree decreased, and the setback was significantly increased. In the case of Ilpum, a mid-late maturing rice variety, the distribution of amylopectin short chains tended to increase when rice was transplanted on June 30^th.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.3
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• pp.366-372
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• 2006

This study is to investigate the physicochemical properties of differently pretreated chestnut starches during starch isolation and to examine their gelatinization properties by both heat and alkali treatments. One kind is starch A made by alkali method from peeled chestnut. The other is starch B made from chestnut with the outer layer. The results are as follows. Starch A has higher water binding capacity of 86.9% than starch B with 80.66%. Swelling powers of both starch A and B increased rapidly from $60^{\circ}C\;to\;80^{\circ}C$ in both, and since then it has changed a bit. Both began to show their solubility at $60^{\circ}C$ and increased continuously as the temperature went up. Starch A has higher swelling power and solubility than starch B. In iodine reaction, starch A has higher ${\lambda}max$ and absorbance at ${\lambda}max$ than starch B. X-ray diffraction patterns showed that starch A is type $C_b$ and that starch B is type B. Starch B has higher relative crystallinity of 37.0% than starch A with 36.2%. The results by differential scanning calorimetry revealed that starch A gelatinized from $66.95^{\circ}C$ to $77.5^{\circ}C$ and its enthalpy is 2.04 cal/g. And starch B gelatinized from $67.09^{\circ}C\;to\;77.5^{\circ}C$, and its enthalpy is 2.29 cal/g. Amylograms of chestnut starch at 6.5% concentration indicated that starch B needs higher onset temperature when beginning to gelatinize than starch A does. But starch A shows much higher peak viscosity, breakdown and setback than starch B does. Starch A shows higher viscosity, gel volume, and optical transmittance in gelatinization properties by alkali than starch B does.

• Journal of the Korean Society of Food Science and Nutrition
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• v.27 no.6
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• pp.1125-1131
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• 1998

The rheological properties of wheat flour dough were investigated in the dough added with 0, 10, 15, 20, 25 and 30% of wheat bran. The ratios of ash contents in wheat flour and wheat bran were 0.43% and 5.28%, respectively. The ratios of fiber contents in wheat flour and wheat bran were 0.18% and 11.86%, respectively. The farinograph water absorption was increased as the amount of wheat bran was increased. Both arrival time and development time of the dough added with wheat bran were longer than those of wheat flour. As the amount of wheat bran was increased, the weakness was increased. The extensograph showed that extensibility and resistance to extension of dough were decreased, while the ratio of resistance to extensibility(R/E) was increased with increasing the amo unt of wheat bran. The maximum viscosity by amylograph was decreased gradually with the adding amount of wheat bran, while the gelatinization temperature was slightly increased with wheat bran.

• Korean journal of food and cookery science
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• v.27 no.2
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• pp.9-17
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• 2011

In this study, the physicochemical properties of polished rice flour, brown rice flour, and Jeung-pyun dough were studied. The protein, lipid, dietary fiber, pH of brown rice flour were higher than those of polished rice flour. The total polyphenol contents and electron donating ability (EDA) of brown rice flour (83.60 mg%, 2.44%, respectively) were higher than those of polished rice flour (56.91 mg%, 1.43%, respectively). The temperature gelatinization of brown rice flour higher than that of polished rice flour. The counts in Jeung-pyun dough were not significantly decreased brown-rice flour. The addition of brown rice flour decreased the amount of carbon dioxide gas evoluted from Jeung-pyun dough. The pH values of brown rice Jeung-pyun dough generally decreased fermentation time.

• Journal of Food Hygiene and Safety
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• v.14 no.1
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• pp.84-89
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• 1999

Octenylscuccinated corn starches prepared by reaction of corn starch with 1-octenylsuccinic anhydride(OSAn) and their degree of substitution (DS), reaction efficiency(RE), residual octenylsuccinic acid (OSA), and physicochemical properties were compared with those of the native corn starch. DS increased with increase of OSAn and RE was much nearly the same regardless of increased of OSAn. The content of residual of residual OSA was significantly lower than that of regulation of food additives. And as washing frequency of dispersion of the reactant was increased, the content of residual OSA of octenylsuccinated starch was decreased. Raid Visco-Analyzer initial pasting temperature and setback of octenylsuccinated starches decreased whereas peak viscosity and breakdown increased. When DS of octenylsuccinated starches increased, temperature of initial gelatinization of octenylscuccinated starches drastically decreased. The octenylsuccinated starches also formed clearer pastes. The solubility was much nearly the same regardless of increase of DS at 7$0^{\circ}C$ but the swelling power increased 1.2~1.7 times higher than that of native corn starch at 7$0^{\circ}C$. The water binding capacity of octenylsuccinated starches also decreased.

• Korean Journal of Human Ecology
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• v.7 no.1
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• pp.11-19
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• 2004

Three rice varieties of Nampyong, Dongjin I, Ilmi produced In Naju were examined for cooking properties. The lipid content of Dongjin I and the protein content of Ilmi were higher than those of others. Total amylose contents of three varieties were in range of 16.1$\sim$-18.6% and that of Ilmi were higher than the others. The initial gelatinization temperature by RVA were ranged from 69.8$^\circ$C to 73. 3$^\circ$C. Peak viscosity and breakdown were the highest in Dongjin I but setback was the lowest. Nampyong had the highest value(p

• Applied Biological Chemistry
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• v.36 no.3
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• pp.146-153
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• 1993

The changes in water uptake rate, cooking property, color of rice grain, gelatinization property of milled rice during storage were studied. The water uptake rate constant of milled rice during storage at $4{\sim}30^{\circ}C$ for 3 months decreased, which was more pronounced at elevated storage temperatures. The activation energy of water uptake was different below and above $25^{\circ}C$ of storage temperature. The activation energy after storage for 3 months below and above $25^{\circ}C$ was 608 and 1269 cal/mole, respectively. The rice grain became harder and the cooking time was prolonged by $3{\sim}8$ minutes upon storage. The cooking rate constant was linearly decreased as a function of storage time. The activation energy of cooking after 1 month of storage was 235 cal/mole, which was increased by 1.7 times after storage of 1.5 months and thereafter by 1.2 times with the increase of 0.5 month. There were no significant changes in color of milled rice grains during storage at $4^{\circ}C$, but the increase of b value was observed at higher temperatures. The Initial pasting temperature of rice flour remained essentially unchanged during storage, but the peak viscosity consistently increased with the increase of storage time and temperature. The gelatinization temperature of rice flour by differential scanning calorimetry was not changed but enthalpy of gelatinization was decreased during storage.

• Korean Journal of Food Science and Technology
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• v.23 no.3
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• pp.341-348
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• 1991

Physicochemical properties and gelatinization patterns of defatted and lipid-reintroduced moist (Hwangmi) and dry (Suwon 147) type sweet potato starches were investigated. Starch granules of sweet potato were polygonal and round, and the sizes of starch granules ranged $5{\sim}13\;{\mu}m$. All starches showed Ca type in X-ray diffraction but relative crystallinity was decreased by defatting and reintroduction. The amylose content of defatted starches increased, but that of lipid-reintroduced starches decreased. The swelling power and solubility at each temperature increased by defatting, but decreased by reintroduction. Transmittance of Hwangmi and Suwon 147 showed a rapid increase at $60,\;65^{\circ}C$, respectively. The initial pasting temperature by amylograph of Hwangmi and Suwon 147 were $67.5^{\circ}C\;and\;72.7^{\circ}C$, respectively. The peak viscosity and the height at $50^{\circ}C$ on amylogram of Hwangmi were lower than those of Suwon 147. Hot paste viscosity and setback decreased by defatting but setbak and consistency drastically increased by reintroduction. The peak temperature for gelatinization by the DSC was $65.7^{\circ}C$ for Hwangmi and $68.5^{\circ}C$ for Suwon 147. The gelatinization temperature and enthalpy of the DSC decreased and amylose-lipid melting peak was lost by defatting. The gelatinization temperature and enthalpy decreased by reintroduction.

• Korean Journal of Food Science and Technology
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• v.18 no.6
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• pp.437-442
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• 1986

Physicochemical properties of chestnut starch, which was adjusted at 14, 18, 21 and 24% moisture and heated for 16 hr at $100^{\circ}C$, were investigated. The cystallinity, swelling power and solubility of the starch were decreased upon heat-moisture treatments. The swelling power of the heat-moisture treated starch showed an inverse relation with moisture levels, while the solubility showed opposite trend. The swelling power and the solubility of both raw and heat-moisture treated starches held a liner relationship. The. water binding capacity of the starch was drastically increased upon heat-moisture treatments. Amylograms revealed that the heat-moisture treated starches had higher initial pasting temperature and lower viscosity than untreated starch. No peak viscosity was observed for the heat treated starches above 21% moisture. The minimum moisture contents for gelatinization of raw and heat-moisture (18%) treated starches were 45 and 40%, respectively. The gelatinization temperature of raw and heat-moisture (18%) treated starches was $65^{\circ}C$.

• Korean journal of food and cookery science
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• v.13 no.5
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• pp.585-591
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• 1997

The proximate composition and physicochemical properties of three cultivars of Korean kidney bean sediments, Pink (PKB), Red (RKD) and White (WKB) were compared. No significant differences in the proximate composition and calorie were noticed among three samples. Sediment granule was oval/round and rough in all samples. The amylograms showed no peak and continuous increase of viscosity during heating. The water-binding capacities of the sediments were 322.4∼355.0%. The swelling power and solubility were 5.93∼6.68% and 3.76∼5.28%, respectively. The percent transmittances of the sediment suspension decreased linearly from 50$^{\circ}$∼75$^{\circ}C$. The gelatinization temperature and gelatinization enthalpy determined by DSC (Differential Scanning Caloriemeter) were much lower than those of starches.