• Korean Journal of Food Science and Technology
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• v.28 no.3
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• pp.528-537
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• 1996

Qualify changes of microwave-reheated cooked rice aseptic-packaged with different lid materials and oxygen absorbers were determined during storage at $20^{\circ}C,\;30^{\circ}C$ and $40^{\circ}C$. Springiness cohesiveness and adhesiveness increased as storage temperature increased, while gumminess and hardness decreased. Lid materials oxygen absorbers, and storage temperatures showed no significant effect on the textural properties of cooked rice after microwave reheating. Degree of gelatinization was increased as storage temperature increased and was restored after microwave reheating. Scanning electron micrograph showed that the surface of cooked rice became rough and hollowed after microwave reheating for 1.5 min, indicating starch was regelatinized, while there was no difference with respect to lid materials. Photomicrographs of the cross-section of aseptic-Packaged cooked rice showed that a compact and solid structure increased and retrogradation occured in starch as storage temperature decreased, while a compact and solid structure was decreased and starch was regelatinized after microwave reheating.

• Applied Biological Chemistry
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• v.35 no.2
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• pp.92-98
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• 1992

Some physicochemical properties and molecular structure of cow pea, mung bean and acorn starches(mook-forming starches) and red bean, wheat and sweat potato starches(mook-unforming starches) were investigated. Amylose contents of cow pea, mung bean and acorn starch were higher than the others. Cow pea starch was similiar to mung bean starch in gelatinization characteristics by Brabender amylogram but cold viscosity of red bean starch and peak viscosity of sweet potato starch were especially high. Whereas viscosity of wheat starch was low in whole temperature range. Amylose molecules of larger molecular size$(above\;5{\times}10^5\;molecular\;weight)$ of three mook-forming starches were more than shoes of red bean and wheat starch. Chain distribution ratios$(DP\;35{\sim}55\;to\;DP\;10{\sim}20)$ of cow pea, mung bean and acorn amylopectin were higher than thoes of red bean, sweet potato and wheat amylopectin.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.2
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• pp.175-180
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• 2003

Effect of the addition of maltitol to Korean rice cake (Karedduk) on its retrogradation was examined. Degree of retrogradation was also examined in terms of recrystallinity of starch and color change with a differential scanning calorimeter. As a result, retrogradation was suppressed by the increasing addition of maltitol. In particular, enthalpy showed a tendency to decrease at $25^{\circ}C$ rather than at 4$^{\circ}C$ during 4 days. In the gelatinization properties using DSC, onset temperature (To) was shown to increase slightly according to storage time. Maximum peak temperature (Tp) was shown to decrease by the addition of maltitol during 4 days. Melting enthalpy was decreased at $25^{\circ}C$ and 4$^{\circ}C$ by the addition of maltitol. The analysis X-ray diffraction also revealed that retrogradation of the Korean rice cake was suppressed by the addition of maltitol because crystalline region did not appear. The addition of maltitol into the Korean rice cake was found to result in an increase of its qualify or color stability.

• Food Science and Preservation
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• v.7 no.4
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• pp.380-383
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• 2000

This study attempted to examine the sensory quality, the degree of gelatinization, color, texture and moisture content of Paeksulgis prepared with different level of Gardenia jasminoides. The moisture contents were about 39∼43% in the Paeksulgies prepared with different level of Gardenia jasminoides. L-value on the control group was high, 93.24. and G$_2$was 90.49, high, but another group were about 82∼86, it was not siginificantly. As the amount of Gardenia jasminoides was increased, a-value on the Paeksulgies was decreased, showed green color. In case of Gardenia jasminoides, b-value of the control group was very low, 10.08. As the amount of Gardenia jasminoides was increased, b-value on Paeksulgies was increased. In sensory quality, Paeksulgies by the amount of 2∼3% water extracted Gardenia jasminoides showed the most favorable sensory evaluation.

• Korean Journal of Food Science and Technology
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• v.38 no.2
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• pp.222-231
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• 2006

Deoxynivalenol (DON)-contaminated barley was treated with 0.1 M $Na_2CO_3$ solution to reduce DON content. DON content of barley was reduced from 2.08 to 0.67 ppm. Bread was made with 10, 20, and 30% DON-reduced barley flour added to white wheat flour. Farinogram showed water absorption and arrival time increased, while stability and mechanical tolerance index decreased when DON-reduced barley flour was added to white wheat flour. Gelatinization temperature, temperature at maximum viscosity, and maximum viscosity increased in amylogram with increasing addition of DON-reduced barley flour. Loaf volume of bread decreased with increasing amount of DON-reduced barley flour, while loaf weight increased. Barley flour pH increased by treatment with$Na_2CO_3$, and pH reduction decreased fermentation rate of yeast. Volume and size of gluten matrix decreased and crumb hardened in bread made with DON-reduced barley flour. Acceptabilities for color and texture were low in bread made with DON-reduced barley flour. Addition of DON-reduced barley flour at 30% reduced overall acceptability, whereas no significant difference in overall acceptability was observed when DON-reduced barley flour was added at 10 and 20%.

• Korean Journal of Food Science and Technology
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• v.19 no.1
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• pp.18-22
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• 1987

Starch granules of cow pea were oval with their sizes of $6-22{\mu}$m. X-ray diffraction pattern of starch granules showed some crystallinity at $2{\theta}$ $15^{\circ}$, $17.1^{\circ}$, $18.1^{\circ}$, $22.9^{\circ}$. The blue value of starch was 0.370, amylose contents 28.1% and water binding capacity 70.6%. Swelling power of the starch increased rapidly from $65^{\circ}C$ to $75^{\circ}C$ thereafter increased less rapidly. Solubility showed the same pattern as the swelling power. Optical transmittance of 0.2% starch suspension was increased rapidly from $70^{\circ}C$ and the gelatinization between $70^{\circ}C$ and $90^{\circ}C$ was single stage. Amylogram of 4% starch solution showed no peak viscosity but 6% starch solution showed peak viscosity.

• Journal of the Korean Society of Food Culture
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• v.31 no.6
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• pp.616-623
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• 2016

This study evaluated the quality characteristics of dried noodles prepared with doenjang powder (0, 3, 6, 9%) in order to determine the most preferred noodle recipe. The proximate composition of the composite doenjang powder-wheat flours was as follows: calories 365 kcal, carbohydrates 79 g, saccharides 3 g, protein 10 g, fat 0.8 g, and sodium 65 mg. As the level of doenjang powder increased, the content of total amino acids increased; aspartic acid, glutamic acid, tyrosine, and lysine contents increased, in particular. Water-binding capacity decreased as the level of doenjang powder increased. When viscosity of composite doenjang powder-wheat flours was measured by amylography, gelatinization point increased as the level of doenjang powder increased. As the level of doenjang powder increased, L value decreased, whereas a and b values increased. Weight, water absorption, and volume of cooked noodles decreased, whereas turbidity of soup increased. For textural properties, hardness decreased, whereas springiness increased as the level of doenjang powder increased. For overall preference according to the results of sensory evaluation, noodles added with 3% doenjang powder were the most preferred. According to the results, addition of doenjang powder positively affects the overall sensory evaluation of dried noodle, and 3% is the optimal level for addition.

• Korean Journal of Food Science and Technology
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• v.30 no.4
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• pp.803-810
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• 1998

The mechanical and thermal properties of solutions of acorn starch were investigated, to determine the effect of sucrose on the retrogradation. The contents of moisture and amylose of purified acorn starch was 9.35, 27% respectively. From the moecular weight distribution, Mw and Mn of acorn starch were 1,220,432 and 137,201 relatively and the polydispersity of acorn starch was 8.8952. The creep compliance of acorn starch with and without sucrose were decreased with increasing sucrose concentration in the short term. The temperatures of DSC curve of 15% acorn starch solution containg sucrose shifted slightly to higher temperatures with increasing sucrose content. The enthalpy change associated with the gelatinization was increased with increasing sucrose content. After 7 days storage, the creep compliance of acorn starch gel with sucrose were shown higher than acorn starch gel. Regelatinization enthalpy of acorn starch/sucrose/water system was decreased with increasing sucrose content and increased with storage time. In addition, the characteristic temperatures such as onset temperature, peak temperature and conclusion temperature was increased by sucrose addition. Retrogradation ratio decreased with increasing sucrose content, thus sucrose inhibit retrogradation in the long term. Sucrose acts as an antistaling reagents and retatards the retrogradation.

• Korean Journal of Food Science and Technology
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• v.32 no.2
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• pp.258-264
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• 2000

Starches from the eight varieties of rice were analyzed using scanning electron microscope(SEM), differential scanning calorimetry(DSC) and X-ray diffractometry, and tested on the starch-granule susceptibility to 15% $H_2SO_4$ and glucoamylase. The shape of starch granules from normal rice varieties and low-amylose mutants were polygonal while shrunken and floury mutants were globular. According to DSC, starches from Nampung CB243 showed higher onset temperature$(T_o)$, completion temperature$(T_c)$ and Punchilmi, Nampung EM90 showed higher enthalpy$({\triangle}H)$ of gelatinization than others. shr showed the highest hydrolysis rate to 15% $H_2SO_4$ while Nampung CB243 showed the lowest one. Eight varieties of rice starch granules showed A-type pattern on X-ray diffractograms. The lower amylose content rice varieties showed the higher hydrolysis rate treated with glucoamylase.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.5
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• pp.765-769
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• 2001

Starches of flavored glutinous rice were analyzed by using scanning electron microscope (SEM) and differential scanning calorimetry (DSC) and tested on the starch granule susceptibility to 15% H$_2$SO$_4$, glucoamylase and $\alpha$-amylase. The shape of starch granules form flavored glutinous rice varieties was polygonal and the size was 4~6 $\mu$m in diameter. According to DSC, glutinous rice starch showed onset temperature (T$_{o}$) range 59.8~62.5$^{\circ}C$ and KR92021-B-B-42-3-B and KR92021-B-B-165-1-B showed higher enthalpy ($\Delta$H) on gelatinization than others. The starches from KR92021-B-B-5-2-B and KR92021-B-B-42-3-B showed lower hydrolysis rate using 15% H$_2$SO$_4$ than KR92021-B-B-165-1-B. KR92021-B-B-5-2-B showed higher degree of hydrolysis of glucoamylase and $\alpha$-amylase than the others.