• Korean Journal of Food Science and Technology
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• v.23 no.1
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• pp.116-121
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• 1991

The effects of water contents and surfactants, sodium stearoyl-lactylate, sucrose ester and distilled monoglyceride(Dimodan) on wheat starch gelatinization and retrogradation were studied by differential scanning calorimetry. The endothermic peak patterns of starch varied with water content of starch. When water content was less than 30%, gelatinization did not occur. The onset temperature of gelatinization peak of native starch was $59{\sim}60^{\circ}C$ and that of endothermal peak of retrograded starch was $50{\sim}55^{\circ}C$. The enthalpy value of retrograded starch were greatest in the $40{\sim}50%$ water content. In the presence of surfactants, gelatinization temperatures shifted slightly to higher temperatures. DSC endothermal enthalpies of the amylose-lipid complex increased. The degree of retrogradation in starch was lower with surfactant than without surfactant, but enthalpy of amylose-lipid complex did not change during storage.

• Korean Journal of Food Science and Technology
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• v.17 no.1
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• pp.5-7
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• 1985

Effect of phosphate (sodium polyphosphate 85%, sodium hexametaphosphate 7% and potassium phosphate 7%) on gelatinization of nonwaxy and waxy rice starches was investigated with X-ray diffractometry. The minimum moisture content for the gelatinization of nonwaxy starches was lowered in the presence of phosphate. The minimum temperature for the gelatinization of 5% starch suspensions was not altered by phosphate. However, the degree of gelatinigation of rice starches at the same temperature was higher in the presence of phosphate, except waxy rice starch.

• Korean Journal of Agricultural Science
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• v.16 no.1
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• pp.102-110
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• 1989

Surface structure and X-ray diffractogram of gelatinized potato starch on heating temperature, time and additives were investigated by Scanning Electron Microscopy (SEM) and X-ray diffractometry. The results obtained are as follows; Potato starch had an amylose content of 23.5%, and blue value of 0.41. Raw potato starch granuls showed egg form. Destruction of starch granuls increased as gelatinizing time and temperature increased. The degree of gelatinization of potato starch showed to be 90% by X-ray diffractomertry at $70^{\circ}C$. There were no significant differences in degree of gelatinization of potato starch on gelatinizing time and phosphate concentration at $70^{\circ}C$. The degree of gelatinization of sample prepared was higher in presence of phosphate than in absence of phosphate.

• Korean Journal of Food Science and Technology
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• v.26 no.5
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• pp.638-643
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• 1994

Gelatinization and retrogradation properties of modified starches which were prepared by steeping sweet potato at $40^{\circ}C$ for 2, 4, 7 and 10 days were investigated. The peak temperature of gelatinization and enthalpy of untreated starch by DSC were $53.9^{\circ}C\;and\;1.32\;cal/g$, respectively, but those of modified starch were increased by steeping. In gelatinization by alkali, starches with 2, 4 and 7 day steeping showed higher viscosities than untreated starch, whereas the viscosities of starches with 10 day steeping decreased. The clarities in paste decreased during storage in all starches and decreased in starches with steeping. The degrees of retrogradation by ${\alpha}-amylase-iodine$ method were higher in starches with steeping than untreated starch. The enthalpy of retrograded starches by DSC increased by steeping except 4 day steeping starch. The sweet potato extract containing sugar inhibited the retrogradation of starch paste and the degree were higher in residual starches than in untreated starch.

• Korean journal of food and cookery science
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• v.12 no.1
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• pp.46-53
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• 1996

To investigate physicochemical and cooking properties of parboiled rice, choochung paddy processed to parboiled rice by three methods (PL, PT, PA) milled and examined hydration, cooking qualities and firming rate of cooked parboiled rice. The results were obtained as follows. The longer the steaming time during parboiling the larger EMC of soaked parboiled rice. Water uptake rate constants (k) of all the parboiled rice during soaking except for PT rice were generally increased than those of raw rice. The longer the steaming time during parboiling the greater volume increase rate constants ( $k_{v}$) of parboiled rice samples. The glelatinization temperature of parboiled rice flour by DSC was more increased than that of raw rice flour. Gelatinized entalpy was decreased and gelatinization content (%SG: degree of starch gelatinization) was increased by parboiling process. In cooking tests, parboiled rices were harder than raw rice and softness (reciprocal of hardness) was greater PT30, PA, PL30 in turns the cooking time of the parboiled rice took longer 3-10 min than that of raw rice, PL30 took longer time than anyother rices. Cooking water of parboiled rices could be observed lighter turbidities than that of raw rice. Firming rate constants of cooked rice during storage 24 hours were generally decreased by parboiling-processing. The time constants, reciprocal of firming constants of cooked PL30 rice were 2 times slower than those of cooked raw rice.e.

• The Korean Journal of Food And Nutrition
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• v.30 no.3
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• pp.464-472
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• 2017

The qualities of rice cooked on heat plate, induction heat and heat plate with pressure, were investigated. The weight, volume, water soluble index (WSI), hydration by SEM (Scanning Electron Microscope), and gelatinization by DSC (Differential Scanning Calorimetry), as well as the consumer acceptability of cooked rice were analyzed. The weight, volume and WSI of rice cooked on heat plate with pressure were higher than those of rice cooked on heat plate and induction heat. The rice cooked on heat plate with pressure also showed higher degree of hydration and gelatinization, and lower degree of enthalpy of gelatinization than the rice cooked on heat plate and induction heat for 5~15 min. The consumer acceptability revealed that the odor, appearance, taste, texture and overall acceptance of rice cooked on induction heat were better than those of rice cooked on heat plate and heat plate with pressure. During storage in a cooker for 0~12 h, there was a decrease in the consumer acceptability of cooked rice. Overall results indicate that the qualities of rice cooked on induction heat and heat plate with pressure were higher than those of rice cooked on heat plate.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.5
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• pp.770-776
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• 2000

Pasting gelatinization of acorn flours which were prepared with soaked nut and sediment at 7.8$^{\circ}C$ for 0, 1, 2, 3 and 4 days were investigated. The peak temperature of gelatinization of untreated acorn flour (0-0) by Rapid Visco Analyzer was 73.1$^{\circ}C$, respectively, but those of flours were decreased by soaking. Peak viscosity, setback and breakdown of acorn flours were increased by soaking. In addition, consistency was increased by soaking treatment. From the result of the pasting properties, gel formation ability of acorn flour was increased with increasing soaking days of acorn nut and soaking times of sediment. The gelatinization temperature examined by X-ray diffractometry was lowered with increasing of soaking days. The observation of microstructure through a scanning electron microscope revealed that gelatinized acorn flour showed loser their original shape and structure than that of with out soaking treatment (0-0). The degree of gelatinization under the fixed temperature increased with increasing soaking days. From these results, it might be concluded that the increase of soaking days and soaking times is the factor affecting the gelatinization of acorn flour.

• Korean Journal of Food Science and Technology
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• v.28 no.5
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• pp.959-964
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• 1996

The physicochemical and gelatinization properties of rice flours, which were prepared by polishing nonwaxy brown rice (Dongjin byeo), depending on polishing degrees were investigated. The contents of protein, ash, lipid and fiber decreased significantly as the degrees of polishing increased and water uptake of rice grains decreased during hydration. When the surface of the soaked rice grains was examined by the SEM, extensive crack formation was observed. The water binding capacities, swelling power and solubility of rice flour increased as the polishing degree increased. By the amylogram, the initial gelatinization temperatures of rice flour decreased as the polishing degree increased and the peak viscosities, the breakdown and consistency of rice flour increased as the polishing degree increased.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.5
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• pp.838-843
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• 1997

The effects of the addition of apricot juice on Haengbyung qualities were evaluated. The reducing sugar contents, degree of gelatinization, moisture contents, color L value and b value of Haengbyung were decreased but the color a value and hardness were increased during the storage. The reducing sugar contents and gelatinization of Haengbyung with the raw apricot juice was decreased less than those with the steamed apricot juice during the storage. the moisture contents of Haengbyung were decreased less than Baeksulgi. Color b value of Haengbyung with the raw apricot juice was decreased less than that with the steamed apricot juice. The consistence, moistness, texture and overall quality of Haengbyung were generally more favorable than Baeksulgi based upon the sensory evaluation during the storage. Throughout the storage, consistence, moistness and texture of Haengbyung with the rqw apricot juice were generally more favorable than those with the steamed apricot juice. With respect to overall quality, Haengbyung with the addition of 15% apricot juice of rice flour weight was generally the most favorable during the storage.

• Journal of the East Asian Society of Dietary Life
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• v.8 no.2
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• pp.173-180
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• 1998

This study was conducted to examine the sensory quality, the degree of gelatization, pH, color, texture and moisture content of paeksolgi with omija water extracts added. The results of the analysis were as follows : The moisture contents of Paeksolgi were about 36~39%. The L value of the control group was 83.04 The degree of the colour was (L value: 71.82~86.56), (a value: -1.33~+0.78), (b value : 7.84~9.78). As the amount of omija water extracts was increased. the L and a values increased, but the b value showed a similar value, It was found that the yellowness decreases by increasing the soaking time of each type. The gelatinization of Paeksolgi with omija water extracts added was decreased as the amount of omija was increased. The sensory quality of paeksolgi with 5~7% omija water extracts added showed the most favorable sensory evaluation. In view of color, after taste and overall quality, the D$_2$group of Paeksolgi was preferable to the other paeksolgi groups with omija water extracts added.