• Journal of the Korean Society of Food Science and Nutrition
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• v.17 no.3
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• pp.226-232
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• 1988

Non-enzymatic browning is a carbohydrate dehydration reaction, accelerated thorough the interaction of amino compounds. Reaction depends on several factors including temperature, reactant concentration, pH, water activity and specific ion concentrations, and result in progressive development of brown pigments in the affected food systems. The present study was designed to utilize a kinetic approach to analyze the effect of temperature and water activity on the browning development in green ten. The green tea was controlled at aw of 0.33, 0.44, 0.52 and 0.65 using saturated salt solutions and then stored at 35,45 and $55^{\circ}C$. Author portion of the sample of which the water activities were controlled in the same manner was stored at 35 and $55^{\circ}C$ alternately with 7 days interval. Simplified kinetic models were used to obtain the various kinetic parameters for browning development in green tea subjected to accelerated shelf-life tests(ASLT). The reaction of browning development was zero order. The activation energies calculated from Arrhenius plot ranged $1.5{\sim}2.4kcal/mole$ and $Q_{10}$ values were between 1.07 and 1.12. These kinetic parameters were then used to predict browning development under the nonsteady storage. Assessed from the parameters the shelf-lives at $25^{\circ}C$, the time to reach 1.02 O.D./g solid at which severe brown color change could be detectable, ranged 57 to 113 days and showed decrease with increase in aw. The predicted shelf-lives at different water activities were a little higher than actual values.

• YAKHAK HOEJI
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• v.46 no.2
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• pp.129-136
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• 2002

The pathogenesis of cholestatic liver injury as well as the modulation of hepatic fibrogenesis is causally associated with involvement of reactive oxygen species (ROS) and free radical reactions. In this study, we investigated whether dried extracts of oriental medicine (LH) have antioxidant and antifibrotic effect under the biliary liver fibrosis (cirrhosis) c ondition. The female Sprague-Dawley rats were divided in six groups (Normal, N-LH, op-2, op-4, opLH-2, opLH-4) and were observed in 2 weeks or 4 weeks. For this purpose the rats were operated by bile duct ligation/scission (BDL/S), which induced to liver fibrosis and cirrhosis. After surgery, the prepared LH was administered p.o. 2 mι/day/rat in 2 weeks or 4 weeks for opLH groups. During the observation period, jaundices appeared in eyes, ears and tail of all BDL/S operated rats. And at the time of sacrifice, cholestasis was observed in proximal bile duct, especially the color of bile juice and urine in opLH-4 group showed more clear than op-2, op-4 and opLH-2 group. The value of clinical parameters and product of lipid peroxidation (MDA) in sera and the hydroxyproline (hyp) content in liver tissue were significantly increased in all liver fibrosis (cirrhosis) developed rats (p＜0.001~0.05). Among the clinical parameters of sera, value of BUN, ALP in opLH-4 group showed significantly lower than in op-4 group (p＜0.05, p＜0.001). The content of hyp in opLH-2, opLH-4 group (478.0 $\pm$ 134.3 $\mu\textrm{g}$/g 897.5 $\pm$ 118.2 $\mu\textrm{g}$/g) showed lower than in op-2, op-4 group (528.9 $\pm$ 220.7 $\mu\textrm{g}$/g, 1023.8 $\pm$ 277.1 $\mu\textrm{g}$/g) and then the value of MDA in opLH-4 was also significantly reduced to 59.4% of that in op-4 group (p＜0.001). The histological change (bile duct proliferation, fibrosis, collagen bundle) was similarly observed in op-2 group and in opLH-2 group, but the weak fibrosis and bile duct proliferation were observed in opLH-4 group compared with in op-4 group. Our data indicate that the 4 weeks treatment with LH extract suppressed lipid peroxidation and inhibited fibrotic (cirrhosis) process, and experimental cholestatic liver disease is associated with increased lipid peroxidation in BDL/S operated rats. Hence we concluded that the measurement of MDA and hyp can be useful monitor for the screening of antioxidant and antifibrotic effect in experimental liver fibrosis (cirrhosis), and LH has been shown to have hepatoprotective effect, antifibrotic effect and antioxidant effect.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.22 no.2
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• pp.73-77
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• 2012

Co-(0.8 wt%) and Ce-(0.4 wt%) doped cubic zirconia ($ZrO_2$ : $Y_2O_3$ = 80 : 20, 70 : 30, 60 : 40, 50 : 50 wt%) single crystals grown by a skull melting method were heat-treated in $N_2$ at $1000^{\circ}C$ for 5 hrs. The orange, yellowish brown and brown colored as-grown single crystals were changed into either brownish red, yellow and green color after the heat treatment. Before and after the heat treatment, the YSZ (yttria-stabilized zirconia) single crystals were cut for wafer form (${\phi}6.5mm{\times}t2mm$). The optical and structural properties were examined by UV-VIS spectrophotometer and X-ray diffraction. Absorption by $Ce^{3+}(^2F_{5/2,7/2}(4f){\rightarrow}^2T_g(5d^1))$, $Co^{2+}(^4A_2(^4F){\rightarrow}^4T_1(^4F)$ or $^4T_1(^4P))$ and $Co^{3+}$, change of ionization energy and lattice parameter were confirmed.

• Journal of the Korean Association of Geographic Information Studies
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• v.16 no.4
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• pp.153-170
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• 2013

This study was conducted to analyze the thermal comfort in the urban neighborhood park and to obtain a plan for improvement of the thermal environment. First, in the result of the analysis of the distribution characteristics of the park's main thermal environment factors and differences among types of space, temperature, relative humidity, and wind speed did not show a clear difference spatially. However, the median radiant temperature showed great differences according to the openness of the space and the covering material. According to the evaluation of thermal comfort by types of space based on derived thermal environmental factors, the PMV value of the square was the highest at 4.39, the paths showed 2.58, greenery 1.90, and resting spaces 0.42. In the result of the PMV regression model established for the evaluation of the significance of these thermal environment factors that decide thermal comfort, it showed that the relative significance to the PMV was as follows in decreasing order: median radiant temperature(1.084), wind speed(-0.280), temperature(0.013), and relative humidity(-0.009). When conducting a scenario analysis on the areas with need for improvement in thermal environment, it was found that through reflectivity, color and the change in the physical properties of packing materials the thermal comfort felt by the body could be improved, and it is believed that through this the improvement plan can be established.

• Food Science and Preservation
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• v.14 no.5
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• pp.439-444
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• 2007

This study was carried out to analyze the quality change of salted mackeral treated with extracts of edible plan(Diospyros kaki, Teucerium veronicoides and Zanthoxylum schinifolium) during storage for develope of preparation methods and high quality of mackerel. The Hunter's color values of salted mackerel was not changed during strange. L, a and b value of salted mackerel teated with Korean herbal extracts was lower changed than those of control(mackerel not treated extracts of edible plants). Adhesiveness, and viscosity of salted mackerel was higher at $4^{\circ}C$ during storage than those at $25^{\circ}C$, and was higher in groups treated extects of edible plants at early storage than those in control group. Hardness was low in the salted mackerel treated extracts of edible plane and control group during storage. The salted mackerel treated Z. schinifolium extracts was the highest scores in sensory evaluation among groups.

• Korean journal of food and cookery science
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• v.27 no.5
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• pp.589-597
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• 2011

This study was performed to evaluate the physiological and sensory properties of breads with different ratios of persimmon peel. Moisture activation of the bread loaf decreased as storage period increased with a smaller range of decrease in the persimmon peel added group. The amount of weight increased, and volume fell to some degree. Adding persimmon peel increased the RVA temperature, whereas maximum decreased. The color change during storage was due to the addition of control and 4% in group a values except there was no significant difference. As the result of measurements using a texture analyzer, hardness, springiness, cohesiveness, gumminess, and chewiness properties decreased. The sensory test results revealed that the 4% and 6% added persimmon peel bread was the best.

• Journal of Korean Academy of Nursing
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• v.23 no.3
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• pp.431-452
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• 1993

This study was done to determine the effect of music therapy on stress and quality of life in patients undergoing hemodialysis. The research design was a nonequivalent control group pre -post test design. The subjects consisted of 21 patients who received hemodialysis in two hospitals located in Kwang Ju. The fourteen receiving treatment in one hospital were assigned to the experimental group and the seven in the other hospital to the control group. Data were gathered from December 14, 1992 to January 16, 1993 through questionnaires and physiological measurement. Data were analyzed by the SAS package using frequency, t-test, paired t-test and Pearson Prod uct - Moment Correlation Coefficient. The results of this study are summarized as follows ; 1. There were no significant differences between the two groups on stress scores and quality of life scores before the treatment. 2. The mean score on the psychological stress scale for the patients undergoing hemodialysis was 2.48 out of a maximum mean score of four, the items with high stress scores were “feeling of weakness and annoyed by everything”, “limitation of food”, “limitation of fluid”, “change in skin color” in that order. The psychological category showed the highest stress score followed by developmental, scoioeconomic and physiological stress categories in that order. 3. In the experimental group, post - test diastolic blood pressure decerased significantly(t=3.24, p=0.0064), but in the control group pre and post - test diastolic blood pressure were not different. 4. There was no difference between the two groups on the pre and post -test psychological stress scores or the depression scores. 5. The mean score of quality of life for patients undergoing hemodialysis was 2.75 out of a maxi-mum mean score of five. The category of ‘emtional state’ showed the highest score followed by ‘self - esteem’, ‘physical state and function’, ‘economic life’, ‘relationship with neighbors’ and ‘family relationship’ categories in that order. There was no significant difference in the pre and post - test quality of life scores between the two groups. 6. Hypothesis 1 that patients undergoing hemodialysis who received music therapy would have less stress than patients undergoing hemodialysis who did not receive music therapy is divided into two sub - hypotheses. 1) The first sub-hypothesis that patients undergoing hemodialysis who received music therapy would have less physiological stress than patients undergoing hemodialysis who did not receive music therapy was partly supported. Among three physiological stress indices (pulse, systolic blood pressure, diastolic blood pressure), only diastolic blood pressure decreased significantly after the treatment in the experimental group. 2) The second sub-hypothesis that patients undergoing hemodialysis who received music therapy would have less psychological stress than patients undergoing hemodialysis who did not receive music therapy was not supported. Psychological stress score and depression score were not significantly different before and after the treatment. 7. Hypothesis 2 that patients undergoing hemodialysis who received music therapy would have a higher quality of life score than patients undergoing. hemodialysis who did not received music therapy was not supported. There were no significant changes in the quality of life scores before and after the treatment.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.10
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• pp.1178-1185
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• 2017

Two types of kimchi with a different total acidity (TA, 0.75% or 1.19%) were heated at $100^{\circ}C$ for up to 60 min to develop a gratin added with heated-kimchi. Their browning index and color intensity increased with increasing heating time, which was more apparent for the kimchi with the higher TA. This was attributed to the Maillard reaction facilitated at a higher heat intensity and by the smaller fermentation products. The same tendency was also observed for the antioxidant activities determined by the total reducing capacity, metal-chelating activity, and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity. In particular, heating kimchi at $100^{\circ}C$ only for 10 min increased the activities significantly. Therefore, the heated-kimchi was added to gratin at 20%. With the addition, the dietary fiber, ${\gamma}-aminobutyric$ acid (GABA) and ornithine contents in the gratin were increased appreciably (P<0.01). Nevertheless, there was little change in its salinity. The antioxidant activities of the gratin were significantly (P<0.001) higher than the control gratin without kimchi, with DPPH radical scavenging activity being 3.6 times higher. The results suggest that the functionality of kimchi could be effectually added to gratin even after heat treatment.

• Journal of the Korean Society of Food Science and Nutrition
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• v.25 no.5
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• pp.779-785
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• 1996

The qualities of bread and change of phytic acid during breadmaking with whole wheat flour were investigated. The ratios of ash contents in wheat flour and whole wheat flour were 0.41% and 1.57%, respectively. The ratios of fiber contents in wheat flour and whole wheat flour were 0.14% and 1.83%, respectively. In amino acid analysis, glutamic acid was determined to be 32~36g/100g protein, which was the highest. Lysine, glycine, arginine and aspartic acid were higher in whole wheat flour than those of wheat flour. Proline, glutamic acid, and phenylalanine were higher in wheat flour than those of whole wheat flour. The ratio of phytic acid content in wheat flour and whole wheat flour was 0.312% and 0.734%, respectively. The content of phytic acid during beadmaking was decreased approximately 65% after proofing, while this was almost constant in the process of oven baking. The content of phytic acid in bread with 3% yeast had less hydrolysis than that in bread with 5% yeast during breadmaking. The phytic acid content in the 0.1% yeast food was decreased more than the 0, 0.3, and 0.5% yeast food groups. As the amount of whole wheat flour increased, the volume of bread was decreased, and color became dark. The sensory evaluation was showed the quality of bread to be the highest when the amounts of coarse whole wheat flour and fine whole wheat flour was 20% and 30%, respectively. Though the amount of coarse whole wheat flour and fine whole wheat flour were increased up to 30% and 50%, respectively, external characteristics of bread was remained in normal.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.10
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• pp.1461-1466
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• 2006

The objective of this research was to investigate the potential use of Prunus mume liqueur byproduct (PLB) as an ingredient in noddle processing. After boiling, the weight and volume of PLB added noodles and turbidity of the noodle soup decreased significantly, compared with those of the control. In sensory evaluation, appearance and color scores of the noodle with PLB were lower than those of the control. However, scores for texture, flavor, taste and overall acceptability were higher in the noodle with PLB than in the control. The pH value of the noodle decreased with increase of PLB concentration and did not change during storage for 30 days at $10^{\circ}C$. Changes of titratable acidity in the noodle with PLB showed the same trend as pH. The surface of the noddle was covered with mold in the control and 10% PLB added noodle after 15 days storage at $10^{\circ}C$. However, the noodle with 20% and 30% PLB did not how significant increase in total bacteria up to 30 days at $10^{\circ}C$.