• The Korean Journal of Food And Nutrition
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• v.14 no.6
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• pp.596-604
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• 2001

Twelve varieties of Korean rice and ten varieties of Japanese rice were selected. After being milled. they were analyzed about various physicochemical properties such as moisture, protein and amylose, a -amylase activity, gelatinization properties. And after being cooked with proper amount of water texture and other physical properties were measured by Texturometer, Tensipresser and Rheolograph-micro. Finally the sensory evaluation test was carried out. The results were as follows. 1. In case of protein contents, amylose contents and $\alpha$-amylase activity, Korean rice had a slightly higher value than Japanese As a consequence. Korean rice showed a little stronger hardness and a little weaker stickiness compared with Japanese rice. 2. Amylose contents showed very high correlation with other physicochemical properties and peak viscosity and gelatinization temperature of RVA, the ratio of stickiness to hardness( -Hl/Hl ) of Texturometer and the tan $\delta$(the ratio of dynamic loss to dynamic viscoelasticity) of Rheolograph-micro showed high correlation with other analyzed properties. 3. The ( -/+)work balance of low compression test(25% ) of Tensipresser analysis(texture analysis on the surface of cooked rice) and tan f of Rheolograph-micro showed very high correlation with sensory evaluation results. By using this parameters as major independent variables, some trials to derive high confidence multiple regression equations were accomplished. By the equations it would be possible to make an approximate pre-estimate of eating quality for unknown japonica rice.

• Journal of the East Asian Society of Dietary Life
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• v.24 no.3
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• pp.368-374
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• 2014

We investigated the physical and cooking properties of commercial noodles supplemented with functional ingredients. RVA (rapid visco analyzer), color, water activity, texture and cooking properties were tested. Noodles containing kudzu showed the highest initial gelatinization temperatures, whereas noodle containing kelp displayed the highest peak viscosity and set back. Holding strength and final viscosity were highest in noodles containing mugwort. The L value ($94.89{\pm}0.02$) of wheat flour noodle was the highest. Among functional noodles, L value ($88.65{\pm}0.01$) and a value ($7.42{\pm}0.02$) of cactus noodle were the highest, whereas b value of pumpkin noodle was $40.81{\pm}0.03$, which was higher value than in other noodles. Water activity of cactus noodle was highest (0.455), but the difference was not significant. Cooking properties (including weight, volume, and water absorption) and turbidity of pumpkin noodles showed the highest growth rate. In terms of texture, hardness was highest ($12836.8{\pm}7.1g/cm^2$) in green tea noodles, and cohesiveness and gumminess were highest in kelp and mugwort noodles. Considerig the quality characteristics of noodles supplemented with mulberry leaves, cactus, mugwort, green tea, pumpkin, kelp or kudzu, pumpkin noodles were most stable in terms of gelatinization and cooking properties.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.1
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• pp.87-92
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• 2005

This study was investigated to examine gelatinization properties of waxy black rice starches. X-ray diffraction patterns in raw starches showed traditional A type of cereals. The crystalline regions of both black rice and Shinsunchalbyeo starches disappeared when temperature increased to $65^{\circ}C$ where the crystalline regions of two starches changed to amorphous ones. Scanning Electron Microscope showed that granule type of Shinsunchalbyeo starch was more collapsed compared to that of black rice starch heated at 6$0^{\circ}C$. Gelatinization in both samples completed when samples were heated at 63$^{\circ}C$. The results by Differential Scanning Calorimetry (DSC) revealed that gelatinization patterns were similar in both samples. In Rapid Visco Analyzer examination, there was no difference in peak viscosity, breakdown, final viscosity and setback between Shinsunchalbyeo and waxy black rice starches.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.9
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• pp.1405-1409
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• 2010

The compositions of fatty acid and amino acid of specialty rice which includes colored rice (Heugjinju, Jeugjinju, Josangheugchalbyeo), flavored rice (Heughyangmi, Hyangmi1), and giant embryo rice (Keunnun) were determined and compared to those of regular rice (Ilpumbyeo, Whaseonchalbyeo). Major fatty acids were linoleic acid (C18:2) and oleic acid (C18:1), which were composed of 75~80% of total fatty acids. Major amino acids were glutamic acid and aspartic acid in most cultivars but Jeugjinju in which cysteine (169.61 nmol) and GABA (129.32 nmol) were the most abundant amino acids. Thermal properties measured by differential scanning calorimeter (DSC) revealed that the enthalpy (${\Delta}H$) for starch gelatinization was the highest in Josangheugchalbyeo and Whaseonchalbyeo. It suggests that the starch structure of waxy rice could be more crystallized compared to non-waxy rice, and also that amylopectin could have more impact on starch gelatinization than amylose. The on-set and complete temperature for starch gelatinization were higher in colored rice of Heugjinju and Jeugjinju, and regular rice of Whateonchalbyeo.

• Korean journal of food and cookery science
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• v.18 no.2
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• pp.157-163
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• 2002

The gelatinization and retrogradation properties of rice starch added with dietary fibers from sikhe were investigated. The pasting temperature and setback of starch measured by using a rapid visco analyzer were increased by the addition of the fiber, whereas the peak viscosity, trough viscosity, end viscosity, breakdown and consistency were lowered. The onset temperature of starch measured by a DSC was increased, but the enthalpy of gelatinization of the starch was decreased as the addition of fiber increased. The melting peak temperature of the retrograded starch gels was 41∼46$\^{C}$ as measured by a DSC. The melting enthalpy of the control retrograded starch gel was increased while storing for 1, 3 and 7 days at 4$\^{C}$, but that of containing sikhe fiber showed no differences.

• The Korean Journal of Food And Nutrition
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• v.25 no.4
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• pp.762-769
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• 2012

In order to study the cooking characteristics of four rice cultivars of Seolhyangchal, Baegjinju, Ilpum and Haiami, we investigated the relationship between the textures of cooked rice and their physicochemical properties. Different levels in grain weight. length/width ratio and amylose content were observed among the four rice cultivars. There was no significant difference in the amylopectin chain length distribution among the cultivars. Water absorptions of rice grains during soaking were completed between 30 and 40 min, with Haiami showing the slowest absorption. Significant differences in the viscosity properties of rice flour were found by a Rapid Visco Analyser. Baegjinju with low amylose content had the highest viscosity in paste breakdown. According to the DSC results of rice starches, there were significant differences in the onset, peak and conclusion temperatures of the endothermic peak. Gelatinization enthalpy showed energy content changes between 4.20 and 6.97 J/g, with the lowest change in Haiami. Texture properties of cooked rice were assessed using a Texture Analyzer, which showed that the hardness of cooked rice was decreased with soaking than without soaking. However, this finding was not applicable for Haiami rice.

• Korean journal of food and cookery science
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• v.24 no.1
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• pp.31-38
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• 2008

Sulgidduk samples made with additions of 1, 2, 3, 4, and 5% Ulmus cortex powder, and a control, were examined for quality characteristics such as moisture content, color, gelatinization properties, textural characteristics, and consumer acceptance, in order to determine the optimal ratio of Ulmus cortex powder in the formulation. The moisture contents among the samples were not significantly different, ranging from 40.57 to 42.37%, and increased as the Ulmus cortex powder content increased. For the color values, lightness decreased and yellowness and redness increased with increasing Ulmus cortex powder content. With regard to the gelatinization properties, peak viscosity (P), trough viscosity (T), final viscosity (F), breakdown, and consistency increased with increasing amounts of Ulmus cortex powder. Pasting temperature, time to peak viscosity, and setback presented decreasing tendencies with the additions of Ulmus cortex powder. For the textural characteristics, increasing Ulmus cortex powder content presented decreases in hardness, springiness, and chewiness however, adhesiveness, cohesiveness, and gumminess were not significantly different among samples. In the consumer acceptance test, the scores of all evaluated characteristics decreased as the ratio of Ulmus cortex powder increased. However, the intensity ratings for the 1 and 2% Ulmus cortex powder samples showed the opposite effect, obtaining fairly good scores. In conclusion, the results indicate that adding $1{\sim}2%$ Ulmus cortex powder to Sulgidduk is optimal, providing good physiological properties and reasonably high consumer acceptability.

• Korean journal of food and cookery science
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• v.24 no.1
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• pp.23-30
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• 2008

Sulgidduk samples made with additions of 2, 4, 6, 8, and 10% Houttuynia cordata Thunb. powder, and a control were examined for quality characteristics such as moisture content, water activity, color, gelatinization properties, textural characteristics, and sensory qualities in order to determine the optimal ratio of Houttuynia cordata Thunb. powder in the formulation. The moisture contents among the samples ranged from 41.98% to 44.97%, and increased as the content of Houttuynia cordata Thunb. powder increased. The water activities of the samples were not significantly different. As the Houttuynia cordata Thunb. powder content increased, the redness and yellowness of the samples also increased, but lightness decreased. For the gelatinization properties, the additions of Houttuynia cordata Thunb. powder caused decreases in peak viscosity (P) and holding strength viscosity (H). Furthermore, final viscosity (F), setback, and time to peak viscosity decreased with increasing Houttuynia cordata Thunb. powder content; however, breakdown and temperature to peak viscosity were not significantly different among the samples. Hardness and gumminess decreased with increasing Houttuynia cordata Thunb. powder content, and adhesiveness, cohesiveness, chewiness, and resilience also tended to decrease; however, springiness was not significantly different among the samples. In the consumer acceptance test, as the content of Houttuynia cordata Thunb. powder increased, the scores of all evaluated characteristics decreased; while the characteristic intensity ratings showed the reverse effect, and the 2 and 4% Houttuynia cordata Thunb. powder samples obtained fairly good scores. In conclusion, the results indicate that adding $2{\sim}4%$ Houttuynia cordata Thunb. powder to Sulgidduk is optimal, providing good physiological properties and reasonably high overall consumer acceptability.

• Korean journal of food and cookery science
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• v.6 no.4 s.13
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• pp.33-39
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• 1990

Rice and waxy rice starches were adjusted to 27% of moisture and heated at $100^{\circ}C$ for 16hours, respectively. After the treatment, their gelatinization properties were investigated. The initial gelatinization temperature, obtained by transmittance and amylogram, of Akkibare and Taebaek starches were $60{\sim}65^{\circ}C$ but those of waxy rice and the U.S.A. rice starches were $55{\sim}60^{\circ}C$ and $70{\sim}75^{\circ}C$, respectively. The gelatinization temperatures of heat-moisture treated starches were higher than those of the untreated starches. Viscosities at each temperature and the highest viscosity reduced by some degrees after the treatment. DSC thermograms of all starches showed single endotherm and the gelatinization enthalpies were $2.26{\sim}2.63\;cal/g$. The gelatinization enthalpy tended to decrease after the treatment. Transmittance and viscosity by alkali showed in this order; Akkibare and Taebaek starches>waxy starch>the U.S.A. rice starch. The heat-moisture treated starches increased viscosities in every starch. Transmittance in alkali solution of Akkibare, Taebaek and waxy rice starches decreased. but that of the U.S.A. rice search increased.

• Korean Journal of Food Science and Technology
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• v.17 no.1
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• pp.33-36
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• 1985

Some properties of starches from three naked barley cultivars(Songhak, Youngsan and Jinan 56) were compared. No significant differences in water-binding capacity, amylose content, relative crystallinity, swelling power and gelatinization degree at various pasting temperatures among cultivars were observed. However, starches showed characteristic viscograph indices and viscosity development patterns in aqueous sodium hydroxide solution. Songhak starch exhibited the lowest pasting temperature and was the most resist to alkali gelatinization.