• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.8
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• pp.1189-1194
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• 2011

This study was conducted to compare the quality characteristics of Korean traditional wine fermented from different rice cultivars. Two kinds of rice cultivars, Seolgaengbyeo and Chucheongbyeo, were used. The hardness values of Seolgaengbyeo and Chucheongbyeo were 2126.6 g/sec and 4056.1 g/sec. The alkali digestion value (ADV) and amylose contents of Seolgaengbyeo and Chucheongbyeo were 6.6 and 6.4, 19.8 and 19.3%, respectively. Amylogram results were not significantly different between Seolgaengbyeo and Chucheongbyeo using a rapid visco analyzer (RVA). After fermentation for 7 days, the alcohol contents of the fermented wines ranged from 17.34 to 17.53%. The pH, total acidity, and glucose contents of the wines fermented with Seolgaengbyeo and Chucheongbyeo were 3.63 and 3.64, 0.17 and 0.17 mg/mL, 3.22 and 3.65 mg/mL, respectively. Finally, sensory evaluation of wine fermented with Seolgaengbyeo showed better taste than that of wine made with Chucheongbyeo.

• Journal of the East Asian Society of Dietary Life
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• v.18 no.5
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• pp.760-765
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• 2008

This study was performed to analyze the properties of the endosperm components of two pigmented rice varieties, glutinous and non-glutinous rice. Apparent amylose contents (AAC) of starch endosperm were 13.72% and 12.05% in pigmented non-glutinous rice and pigmented glutinous rice, respectively. Both initial temperatures for gelatinization of the two pigmented rice varieties were lower than that of milled rice. The enthalpy for gelatinization of pigmented non-glutinous rice was similar to that of milled rice, but higher than that of pigmented glutinous rice. Pigmented glutinous rice showed the highest Mg/K ratio, which affected the glutinosity in cooked rice. No difference was found in amino acid content among the various groups; however, the lysine contents were higher in the two pigmented rice varieties compared to milled rice. There was no difference in the fatty acid composition among the groups tested. Moreover, the major components of fatty acids were palmitic acid, oleic acid, and linoleic acid in the two pigmented rice varieties and milled rice. The breakdown value of gelatinization property by RVA (Rapid Visco Analyzer) was lowest in pigmented non-glutinous rice.

• Korean Journal of Food Science and Technology
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• v.50 no.6
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• pp.587-593
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• 2018

This study was carried out to investigate the effect of roasted rice bran (RRB) on the rheological properties of bread dough. According to farinograph analysis, the consistency of the control sample was greatest. There were no significant differences in water absorption (p<0.05). Lower values of development time, stability, and time to breakdown, which were affected, by the addition of RRB, were observed for RRB-containing dough samples, compared to the control dough sample. Addition of RRB significantly increased the mixing tolerance index (MTI). According to rheofermentometer analysis, the values of H'm, $T^{\prime}_1$, and retention volume decreased with increase in the amount of RRB added. According to the rapid visco analyzer (RVA) analysis, peak viscosity, holding strength, and setback values were greater in the control than in the RRB-containing samples. The addition of RRB to the flour influenced rheological properties like fermentation volume and acidity. The total acidity increased with the increase in the amount of RRB added. The present study has indicated that there was no significant difference between the rheological properties of the control and 5% RRB-containing dough samples. Therefore, the addition of 5% RRB could be an effective way to produce functional flour bread without affecting its desirable physical properties.

• The Korean Journal of Food And Nutrition
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• v.25 no.3
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• pp.656-663
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• 2012

Two sorghum(Sorghum bicolor L. Moench cv. Hwanggeumchal-susu and Miryang 3) samples were milled using different milling methods, and their physicochemical properties were tested. Particle size was classified into five groups such as pin mill and low temperature-microparticulation(LTM; 10,000, 20,000, 30,000, and 40,000 rpm). The water absorption index (WAI), water solubility index(WSI), and a rapid Visco analyzer(RVA) were used to examine particle size distribution and color differences. Particle size of sorghum flour prepared using LTM was lower than that prepared using a pin mill. Particle size was further reduced by successive dry milling of the LTM flour. Lightness of colored pigments increased when particle size decreased. The WAI of Miryang 3 pin milling(M1) flour was the lowest after LTM, and WSI was higher in the order of M2, M3, M4, and M5. LTM sorghum flour had significantly higher pasting viscosity, as determined using a rapid Visco analyzer. LTM Miryang 3 sorghum flour(M2~M5) flour showed lower breakdown viscosity and higher final viscosity compared to those of M1 flour, resulting in an increased setback value.

• Food Engineering Progress
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• v.15 no.1
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• pp.56-63
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• 2011

Durum wheat semolina was added into wet-milled rice flour in order to improve chewy texture, firm bite ("al dente"), and resistance to overcooking of the ordinary rice noodles. Wet noodles were prepared by mixing 0 (control), 5, 10, 15, and 20% (w/w) of semolina per semolina and rice flour mixtures. Vital gluten (4%, w/w) and salt (2%, w/w) were added to form the pliable strands of wet noodles and final moisture contents of the raw mixtures were equalized at 45%. Pasting properties of the suspended flour mixtures as measured by the Rapid Visco Analyser (RVA) showed slight increases (up to $1.2^{\circ}C)$ in pasting temperatures along with the considerable decreases in peak viscosities as semolina increased at over 15%. Reduced shear thinning and retrogradation of the starch solution that leads to hardening of the cooked noodles were indicated by lowered breakdown viscosities and gaps between finaland setback viscosities from the RVA viscogram as semolina increased at over 10%. Reduced water uptake and turbidity increases of the cooking water as caused by the soluble starches from the noodle were also noted as the content of semolina increased. More or less significant (p<0.05) decreases in colorimetric L (lightness) value of the raw- and cooked noodles were observed as semolina increased while a- (redness) and b (yellowness) values were rather increased at the same moment. Textural properties of the cooked noodles such as hardness, springiness, cohesiveness, gumminess, and chewiness from TPA tests were significantly (p<0.05) influenced by added semolina, even at 5%-levels or more. It can be concluded that addition of semolina into rice flour could provide easy handling of the wet noodles without distortion during transportation, integrity and firm bite of the cooked noodles, and less loss of starch to the cooking water in comparison with the ordinary rice noodle. It was finally suggested that optimum level of the semolina in the product was approximately 10% for the quality wet rice noodle products.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.12
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• pp.1797-1801
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• 2011

Two brown rice samples differing in amylose content, 20.1 (normal) and 7.3% (low amylose) were milled by different milling methods, and their physicochemical properties were tested. Particle size of brown rice flour prepared by dry milling using a pin mill (DM) was lower than that prepared by wet milling using a roll mill (WM). Particle size was further reduced by successive dry milling of the flour after wet milling and drying (WM/DM). Damaged starch contents in the wet milled brown rice flour were 14.6 and 15.6% for the normal and low amylose samples, respectively, whereas they were only 4.2 and 4.8% for the dry milled samples. WM/DM method resulted in a lower damaged starch (%) than DM, despite a reduced flour particle size. Water absorption index (WAI) of the brown rice flour was the lowest after WM/DM, and the water solubility index (WAI) was higher in the order of DM, WM/DM, and WM. Brown rice flour with normal amylose content appeared to have significantly higher pasting viscosities, as determined using a Rapid Visco Analyzer (RVA). Compared to dry milled brown rice flour, wet milled brown rice flour showed lower peak viscosity and higher final viscosity, resulting in increased setback value.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.9
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• pp.1407-1413
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• 2015

The objective of this study was to investigate the rheological and pasting properties of potato flour dispersions at different concentrations (3, 4, 5, 6, and 7%, w/w). A potato cultivar 'Goun', used in this study, was developed by Highland Agriculture Research Center, RDA. Potato flour dispersions showed shear-thinning behaviors (n=0.44~0.51) at $25^{\circ}C$. Apparent viscosity (${\eta}_{a,100}$), consistency index (K), and yield stress (${\sigma}_{oc}$) significantly increased with an increase in potato flour concentration. Storage modulus (G') and loss modulus (G") significantly increased, whereas complex viscosity (${\eta}^*$) was significantly reduced with increasing frequency (${\omega}$) from 0.63 to 63.8 rad/s. Magnitudes of G' and G" were significantly increased with elevation of potato flour concentration. G' values were considerably greater than G" over the entire range of frequency (${\omega}$) with a high dependence on ${\omega}$. Cox-Merz rule was not applicable to potato flour dispersions. Rapid Visco Analyzer data showed that peak viscosity, trough viscosity, breakdown viscosity, final viscosity, and set back viscosity of samples significantly increased with an increase in potato flour concentration.

• Food Science and Preservation
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• v.23 no.2
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• pp.194-203
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• 2016

The purpose of this study was to investigate the properties of tteok prepared from white (Samkwang) and brown rice (Heugseol, Heugjinju). The moisture and crude protein contents of rice were 14.89~17.15% and 4.79~6.81%, respectively. The crude lipid and crude ash contents of rice were 0.48~2.66% and 0.39~1.60%, respectively. The water binding capacity of Heugjinju (141.97%) was higher than those of other rice flours. As the soaking time increased, water absorption ability was in the order of Samkwang > Heugseol > Heugjinju. Using a rapid visco analyser (RVA), the initial pasting temperature of Heugseol was the highest, and the peak viscosities of Heugseol were higher than those of other rice flours. The quality characteristics of Tteokbokki tteok were assessed after its preparation by adding different amounts of Heugseol and Heugjinju (0, 5, 10, and 20%, w/w) content. The textural properties (hardness), of Heugseol and Heugseol measured using a texture analyzer, were greater than those of the control. Sensory preference tests revealed that 10% Heugseol and, 10% Heugjinju had the highest scores in appearance, color, and overall acceptability. The sensory test results revealed that Tteokbokki tteok prepared by addition of 10% added brown rice was the best.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.329-329
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• 2017

The study was conducted to investigate the effects of different harvesting time on pasting properties of starch in three colored rices. Seven major parameters of starch pasting properties, peak viscosity (PKV), hot pasting viscosity (HPV), cool pasting viscosity (CPV), setback (CPV minus PKV), breakdown (PKV minus HPV), peak time, and pasting time were determined by Rapid Visco Analyzer. The peak viscosity, hot viscosity, cool viscosity and peak time were influenced by different harvesting times. Pasting time was delayed slightly with prolonged harvesting time in all rice cultivars. Pasting temperature in each rice cultivar differed from each harvesting time, and pasting temperature of the two rice cultivars, Hongjinju and Joseongheugchal, showed the highest at the 40 days after heading and then it decreased at the final harvesting time. With the delay of the harvesting time, peak viscosity, hot viscosity, cool viscosity, setback value and pasting temperature did not exhibit a regular trend depending on their genetic characteristics. Branch chain length distribution of amylopectin was demonstrated a distinct difference among these colored rices. In changes of amylopectin branch chain-length distribution, the amylopectin structure of Hongjinju rice cultivar as affected by different harvesting time, the shortest chain length of amylopectin in rice starch harvested at 20 days after heading was characterized by the significant increase in A chains with $DP{\geq}12$ and remarked decrease in long chains $37{\leq}DP$ compared to that of 30, 40, and 50 days after heading. In particular, when harvesting time is delayed the distribution percentage of short chain (A chains with $DP{\geq}12$) was increased except for the rice which harvested 20 days after heading. The similar results were also observed in Sintoheugmi rice cultivar like that of Hongjinju rice cultivar. Otherwise, distribution percentage of the shortest chain length of amylopectin in rice starch harvested at 20 days after heading was characterized by the significant decrease in A chains with $DP{\geq}12$ and remarked increase in B chains $13{\leq}DP{\geq}24$ compared to that of 30, 40, and 50 days after heading.

• Korean Journal of Food Science and Technology
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• v.31 no.3
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• pp.644-650
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• 1999

A normal and a waxy hull-less barley with similar ${\beta}-glucan$ contents were selected, and the effects of ${\beta}-glucans$ on rheological and pasting properties were investigated by using their flour extracts and isolated ${\beta}-glucan$ gum materials. ${\beta}-Glucans$ in the barley cultivars were extracted in a crude form with alkaline extraction, and the waxy hull-less barley produced more ${\beta}-glucan$ gum yield. The waxy barley also showed higher viscosities of water and alkaline flour extracts, compared to the normal barley. Both normal and waxy barley ${\beta}-glucan$ gums exhibited pseudoplastic flow behavior, and increasing ${\beta}-glucan$ concentration increased viscosity in a similar manner. The normal barley flour had a higher amylograph peak viscosity than did waxy barley flour. On the other hand, waxy barley flour with treatment of $HgCl_2$ demonstrated considerably higher increase in peak viscosity. Pasting characteristics of normal and waxy barley starches in the presence of ${\beta}-glucan$ gum solutions were tested using a rapid visco-analyzer (RVA). ${\beta}-Glucan$ gums increased the pasting viscosities of the barley starches, and the synergistic increase in viscosity appeared to be higher in the normal barley starch.