• Korean Journal of Food Science and Technology
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• v.49 no.6
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• pp.625-631
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• 2017

This study was performed to examine the quality characteristics and antioxidant activity of curd yogurt with varying content (0.5-2% (w/w)) of lemon grass hot-water extract (LGHWE). The pH decreased with higher LGHWE content until 8 h, with the treated groups showing higher pH values than the control group after 12 h. The viscosity and the viable cell counts of the yogurt with 2% LGHWE were significantly lower than those of the control group during fermentation. Color values of LGHWE yogurt were lower in terms of brightness, whereas redness and yellowness values were higher compared to the control. The DPPH radical scavenging activity and soluble content significantly increased with higher LGHWE content. Consumer acceptability score of yogurt with 0.5% LGHWE was ranked higher than that of other yogurts. Yogurt containing 0.5% LGHWE showed no differences in pH and titratable acidity compared to control after storage at $4^{\circ}C$ for 14 days.

• Journal of Conservation Science
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• v.35 no.6
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• pp.664-669
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• 2019

Yeonpyo-beob is a method of manufacturing pigments using bamboo trunk and glue solution. Glue solutions of concentrations 1, 5, and 10% were employed to manufacture pigments, and the characteristics of pigment manufacturing were analyzed according to these concentrations. The pigment manufacturing process can be divided into holding and drying phases. The holding phase involves the sedimentation of relatively large particles, whereas the drying phase involves the sedimentation of small particles. The layers formed during the drying phase have almost similar forms regardless of the concentration of the glue solution. If the concentration of the glue solution is low in the holding phase, the particles are mixed and the formation of a layer is difficult. In contrast, when the concentration of the glue solution is higher, the layer of the pigment is more distinct. These results confirmed that the differences in viscosity due to the variation in the concentration of the glue solution affect the sedimentation velocity of the pigment particles, thereby affecting the formation of the layer of the pigment and the pigment manufacture. Consequently, applying 10% glue solution to reduce the sediment velocity is deemed suitable for the stratification of the pigment particles and the manufacture of pigments.

• Journal of the Mineralogical Society of Korea
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• v.28 no.1
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• pp.61-69
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• 2015

While the macroscopic properties and eruption style of basaltic and phonolitic melts are different, the microscopic origins including atomic structures are not well understood. Here we report the atomic structure differences of glass in diopside-anorthite eutectic composition (basaltic glass) and phonolitic glass using high-resolution 1D and 2D solid-state Nuclear Magnetic Resonance (NMR). The $^{27}Al$ MAS NMR spectra for basaltic glass and phonolitic glass show that the full width at half maximum (FWHM) of Al for basaltic glass is about twice than phonolitic glass, suggesting the topological disorder of basaltic magma is larger than that of phonolitic magma. The $^{27}Al$ 3QMAS NMR spectra for basaltic glass and phonolite glass show much improved resolution than the 1D MAS NMR, resolving Al and Al. Approximately 3.3% of Al is observed for basaltic glass, demonstrating the configurational disorder of basaltic magma is larger than phonolitic magma. This result confirms that the topological disorder of Al in basaltic glass is larger than that of phonolitic glass. The observed structural differences between basaltic glass and phonolitic glass can provide an atomistic origin for change of the macroscopic properties with composition including viscosity.

• Korean Journal of Food Science and Technology
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• v.34 no.2
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• pp.213-219
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• 2002

This study was investigated cooking conditions of cooked milled rice added 5%, 7%, 9% and 11% ratios of waxy black and glutinous rices. The L value (lightness) of cooked milled rice added waxy black and glutionus rices were decreased according to increase added ratios, the a value (redness) of waxy black rice was decreased and b value (yellowness) of glutinous rice was increased while waxy black rice was decreased. In case of cooked milled rice added 9% glutinous rice, it was showed the highest values for springiness, cohesiveness, chewiness, adhesiveness and adhesiveness/hardness ratio except gumminess and hardness and all parameters of waxy black rice in texture analyser was showed the highest values at 9%, but the other parameters except cohesiveness were no significant difference at p<0.05 level. In sensory evaluation, the cooked milled rice added 9% glutinous rice was showed the highest values for flavor, clumpiness and taste and 11% glutinous rice was showed the highest values for color, glossiness, cohesiveness, hardness, adhesiveness and acceptability. Also the cooked milled rice added 9% waxy black rice was showed the highest values for cohesiveness, taste and acceptability and 11% waxy black rice was showed the highest values for flavor, color, glossiness, clumpiness, hardness and adhesiveness. Correlations between sensory parameters of cooked milled rice added waxy black rice and glutinous rice were found a significant relationship between taste and acceptability and the correlation coefficients of cooked milled rice added waxy black rice and glutinous rice were r=0.7153 and r=0.5760, respectively.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.55 no.2
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• pp.177-186
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• 2010

This study was carried out to compare the physicochemical characteristics and preference as a sensory quality of Sogokju (Korean traditional rice wine) from waxy rice varieties. The protein and moisture contents of milled waxy rice varieties were ranged 6.9~7.2% and 12.1~ 12.6%, respectively. Nunbora had the largest grain size. In pasting properties, Hangangchalbyeo had the highest peak, trough and final viscosities, and Dongjinchalbyeo had the lowest viscosity curve. These differences suppose to be caused by the amylopectin(AP) structure: Dongjinchalbyeo has the largest short AP chains (degree of polymerization (DP) 6-12) and the smallest middle AP chains (DP 13-24) in 9 waxy rice varieties, while Hangangchalbyeo has the smallest short AP chains and the largest middle AP chains. The alcohol contents of Sogokju brewed from 9 waxy rice varieties were 17.6～19.9%. The brix degree were ranged $20.5{\sim}23.9^{\circ}Bx$. The organic acid of Sogokju consisted mainly of succinic acid, and the free sugar of it consisted mostly of glucose. The sensory evaluation showed the highest palatability at the Sogokju from Baegseolchalbyeo. The palatability was positively correlated with the brix degree, the glucose content, and the turbidity, and negatively correlated with the production yield of Sogokju.

• Applied Biological Chemistry
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• v.19 no.1
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• pp.36-40
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• 1976

The mucilage of the root of Abelmoschus manihot, MEDIC is important for production of Korean traditional hand-made paper. This study was proceeded to detect the variation of the amount of free reducing sugars and of the viscosity in the mucilage. The results as follow. 1. The mucilage of the root of Abelmoschus manihot, MEDIC has contained some of free reducing sugars, 2. The viscosity of the mucilage isolated from the root decreases with time at the constant temperature, but the amount of reducing sugars show a little change. 3. The amount of the reducing sugars is not changed on the agitation. 4. When $1{\sim}2%$ ammonium sulfate solution is added, the viscosity of the mucilage decreases very gradually, and the amount of the free reducing sugars in the mucilage shows a little change.

• Food Science of Animal Resources
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• v.25 no.3
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• pp.285-294
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• 2005

The objective of this study was to evaluate the physico-chemical properties and flavor compounds of sausages with various levels and molecular weight (MWs) of chitosans, during storage at $4^{\circ}C$. Various MWs (Low: 1.5 kDa; Medium: $30{\sim}50$ kDa; High: 200 kDa) and two levels (0.3 and $0.6\%$) of chiosans were dissolved and measured the viscosity at $4^{\circ}C$, pH values were not affected (p>0.05) by either MWs or levels of chitosans. The addition or high MWs or chitosan into the pork salt soluble protein (SSP) increased the viscosity, whereas no differences were observed in low and medium MWs of chitosan. Textural profile analysis (TPA) was affected by the addition of medium or high MWs of chitosan. As a result, the addition of medium of chitosan increased the hardness, gumminess, chewiness, cohesiveness and springiness values, whereas increased level of chitosan didn't affect TPA values, except few cases. Approximately twenty-nine flavor compounds were identified in the low-fat and regular-fat sausages, however the addition of chitosans didn't impair the flavor composition of the sausages, These results indicated that the addition of chitosans didn't affect the flavor profiles, but affected the textural properties in the sausages, especially MWs higher than 30 kDa.

• Journal of the Korean GEO-environmental Society
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• v.15 no.5
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• pp.31-37
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• 2014

In situ investigations and laboratory tests using elastic wave have become popular in geotechnical and geoenvironmental engineering. Propagation velocity of elastic wave is the key index to evaluate the ground characteristics. To evaluate this, various methods were used in both time domain and frequency domain. In time domain, the travel time can be found from the two points that have the same phase such as peaks or first rises. Cross-correlation can also be used in time domain by evaluating the time shift amount that makes the product of signals of input and received waveforms maximum. In frequency domain, wave propagation velocity can be evaluated by computing the phase differences between the source and received waves. In this study, wave propagation velocity evaluated by the methods listed above were compared. Bender element tests were conducted on the specimens cut from the undisturbed hand-cut block samples obtained from Block 37 excavation site in Chicago, IL, US. The evaluation methods in time domain provides relatively wide range of wave propagation velocities due to the noise in signals and the sampling frequency of data logger. Frequency domain approach provides relatively accurate wave propagation velocities and is irrelevant to the sampling frequency of data logger.

• Food Science and Preservation
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• v.18 no.6
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• pp.830-835
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• 2011

This study was conducted to evaluate the effects of the substitution of flour with young-barley-leaf powder on the quality characteristics of yellow layer cake. The physical properties of the cakes (i.e., viscosity, specific gravity, specific volume, cake index, and color) were measured, and the changes in hardness during the three-day storage at $22^{\circ}C$ were measured. Sensory evaluation was done with five-scale acceptance test. Both the viscosity and specific gravity of the batter were significantly influenced by the substitution. Nonetheless, no significant difference was shown in the specific volumes of the cakes. The volume indices of the cakes containing young-barley-leaf powder were higher than those of the control. The lightness, redness, and yellowness values of the crusts decreased with the addition of young-barley-leaf powder. While the lightness values of the crumbs decreased, the redness and yellowness values increased. The substitution of more than 6% flour with young-barley-leaf powder kept the hardness of the cakes lower than that of the control during the three-day storage. The cakes containing 2, 4, and 6% young-barely-leaf powder showed no significant differences from the control in the acceptance test, except in the crumb color.

• Journal of Dairy Science and Biotechnology
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• v.14 no.2
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• pp.157-164
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• 1996

This study aimed increase the quality during ripening of Cheddar cheese made with proteinase-negative mutant of Streptococcus lactis KCTC 1913 selected by curing. The degradation of protein during cheese ripening were investigated by electrophoresis and chromatography. The results were summarized as follow ; 1. The number of lactic acid bacteria decreased with the ripening stage, and that of the control cheese decreased faster than that of the cheese made with mutant. 2. Polyacrylamide gel electrophoretic analysis of cheese caseins revealed no difference between the cheese made with mutant and the control cheese, but differences along with the ripening stage were evident. 3. On Sephadex G-25 column chromatography, the extracts of bitter components from the green cheese and 3 month ripended cheese were fractionated into 3 fractions. With the progress of ripening, bitter peptides were degraded to rather small peptides or free amino acids. 4. Sensory evaluation of the 3 month ripended Cheddar cheese found no significant differences in color but the cheese made with mutant evidenced higher palatability in flavor and better texture than the control cheese. 5. The yields of the cheddar cheese made with mutant was 0.14% higher than that of the control cheese.