• Korean Journal of Food Science and Technology
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• v.37 no.3
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• pp.438-442
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• 2005

Granule swelling is essential phenomenon of starch gelatinization in excess water, and characteristic of heated starch dispersion depends largely on size and distribution of swelled starch granule. Although swelling characteristic of starch granules depends on type of starch, heating rate, and moisture content, influence of heating rate on swelling phenomenon of starch granule has not been fully discussed, because constant heating rate of starch dispersion cannot be obtained by conventional heating method. Ohmic heating, electric-resistant heat generation method, applies alternative current to food materials, through which heating rate can be easily controlled precisely and conveniently at wide range of constant heating rates. Starch dispersion heated at low heating rates below $7.5^{\circ}C/min$ showed Newtonian fluid behavior, whereas showed pseudoplastic behavior at heating rates above $16.4^{\circ}C/min$. Apparent viscosity of starch dispersion increased linearly with increasing heating rate, and yield stress was dramatically increased at heating rates above $16.4^{\circ}C/min$. Average diameter of corn starch granules during ohmic heating was dramatically increased from $30.97\;to\;37.88\;{\mu}m$ by increasing heating rate from $0.6\;to\;16.4^{\circ}C/min$ (raw corn starch: $13.7\;{\mu}m$). Hardness of starch gel prepared with 15% corn starch dispersion after heating to $90^{\circ}C$ at different heating rates decreased gradually with increasing heating rate, then showed nearly constant value from $9.4\;to\;23.2^{\circ}C/min$. Hardness increased with increase of heating rate higher than $23.2^{\circ}C/min$.

• Food Science and Preservation
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• v.17 no.1
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• pp.42-49
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• 2010

This study was developed a multi-step process of functional jungkwa preparation from jujube fruits to prepare a new processed food, and investigated on the quality of jujube jungkwa. The weight of jujube fruits notably increased during the second processing, compared with jungkwa prepared from dried jujube fruits using an osmosis drying treatment. The weight of jungkwa produced in the second processing step was less than those in the first step. The Hunter values (L, a, b) of dried jujube fruits after the first processing were less than those of control jujube fruits. The L value did not change after the second processing of jujube jungkwa, but the a and b values were markedly decreased. However, the Hunter values did not change during the third processing step. The moisture content of dried jujube fruit, and dried fruit treated by supplementary drying (DDJF) was 37.74 and 35.93%, respectively, and that of dried fruit treated by osmosis drying was 40.42%. The moisture content of dried jujube fruit after the second processing decreased by 2-10%, and by 4-10% after the third processing. The reabsorption ratio of jujube jungkwa after the second processing was 16.93%, and that of jungkwa produced from osmosis-dried fruit 24.81%. The strength and hardness of dried jujube fruit treated with supplementary drying (DDJF) were higher, at 3 and 2, respectively, compared to the values of dried jujube fruit. The rheology of jujube fruit and jungkwa did not change during the second processing. The color, glossiness, acceptability of appearance, flavor, and overall acceptability of dried jujube fruit treated by osmosis drying as the second processing step were somewhat higher than those of fruit processed by other methods. The scores for appearance, flavor, chewiness, after taste, and overall acceptability of dried fruits treated with supplementary drying as the third processing step were somewhat greater than those of fruit prepared by other means. Accordingly, we have developed a process for preparation of jungkwa from dried jujube fruit treated by supplementary drying and osmosis drying as the second and third processing steps.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.4
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• pp.626-632
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• 2004

Of hot- water extracts prepared from 30 kinds of herbal medicines, Acanthopanax senticosus (75.6% inhibition of control), Atractylodes macrocephale (71.3%), Panax ginseng (70.0%), Glycyrrhiza uralensis (66.3%) and Angelica acutiloba (63.1%) showed the potent tumor metastasis inhibition activity against colon 26-M3.1 lung carcinoma at 2.5 mg/kg body weight, whereas the other extracts had a little activity, except for Pueraria thunbergiana (58.6%) and C. leticulata (54.9%) having the intermediate activity. We also found that Citrus leticulata (1.80-fold of control), A. macrocephale (1.73-fold), A. senticosus and G. uralensis (1.64-fold) enhanced on Peyer's patch cells mediated-hematopoietic response at 100 $\mu\textrm{g}$/mL. In addition, these active herbal medicines were prepared into steam distillates to improve the food rheology as beverage, and to remove the inactive components. Among these steam distillates, A. macrocephale, G. uralensis and A. senticosus showed the significant tumor metastasis inhibition activity at 2.5 mg/kg body weight (58.7%, 50.3% and 41.9%, respectively), and A. macrocephale had the potent activity even at 0,25 mg/kg body weight (49.7%). In treatments of steam distillates with Peyer's patch cells, A. macrocephale and A. senticosus significantly increased the bone marrow cell proliferation even at 10 $\mu\textrm{g}$/mL (1.49- and 1.28-fold of control). Although steam distillates had lower activity than hot-water extracts, herbal medicines, such as A. macrocephale and A. senticosus, showed the high immunostimulating activity in hot-water extracts as well as steam distillates. Therefore, these results assumed the possibility that steam distillates from herbal medicines might be utilized to food industry for beverage.

• Korean journal of food and cookery science
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• v.15 no.3
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• pp.203-209
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• 1999

The effect of several hydrocolloids on the rheological behavior of wheat flour was investigated. The influence of the selected hydrocolloids (alginate, carrageenan, CMC, guar, locustbean and xanthan) on wheat flour was tested by using two different techniques; amylograph and texture analyzer. In order to have a general overview of their effects hydrocolloids were chosen from different sources implying a broad diversity of chemical structures. The hydrocolloid addition decreased the brightness(L) but increased yellowness(b). The interaction between hydrocolloid and flour produces a slight modification of the amylogram parameters, being the most clearly affected parameter breakdown, which is increased by carrageenan, guar and xanthan. Hardness and cutting force were augmented by hydrocolloid addition, while springeness was decreased except guar and locustbean. In summary, when looking for the improvement of the noodle texture, guar, locustbean are the best candidate additives due to their effects on pasting and texture properties. These hydrocolloids increase the hardness, cutting force, gumness, chew-ness, so were thought to increase the eating quality. So, each tested hydrocolloid affected in a different way the rheological properties of wheat flour, the results obtained are important for the appropriate use of these hydrocolloid as ingredients in the noodle making process.

• Journal of the East Asian Society of Dietary Life
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• v.18 no.6
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• pp.1022-1031
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• 2008

Pound cakes were prepared with Citrus mandarin powder(CMP) cultivated in JeJu Island, Korea. The impact of CMP amount level, which was incorporated into wheat flour by the ration of 0, 5, 10, 15, and 20% based on a flour weight, on the rheology and sensory profile of the pound cakes was measured. Moisture content of 13.70%, crude protein 5.12%, crude lipid 1.30%, crud ash 1.92%, respectively. Also evaluation was performed on the changes in physicochemical properties of the pound cakes during storage at 4 and $30^{\circ}C$. According to the amylogram, gelatinization temperature of the control dough was $63.35^{\circ}C$ and those of the dough with CMP were $63.85{\sim}66.55^{\circ}C$. Maximum viscosity of the dough was 686 B.U in the control, those were 575 B.U, 553 B.U, 504 B.U and 401 B.U in the dough with 5, 10, 15, and 20% CMP, respectively. The retrogradation degree(setback value) of CMP dough was $31{\sim}57%$ lower than that of the control dough under the same conditions. Water holding capacity of pound cake was increased gradually in proportion to the amount of CMP. The CMP addition decreased the brightuess(L) of pound cakes but increased redness(a) and yellowness(b). Hardness of pound cakes was significantly increased by CMP addition, while springiness, adhesiveness and cohesiveness were decreased. Based on sensory evaluation, pound cakes added with CMP were not significantly different in color and texture, while that of 10% CMP was significantly high in taste, flavor, and overall preferences, compared to the control. pH of pound cake with CMP was decreased during storage, showing that pH of CMP samples was lower than the control. Titrated acidity of pound cake with CMP was increased rapidly from storage for 10 days, which the changes in degree was fast in accordance with CMP amount. The Hunter's color value of pound cake with CMP was decreased, as the storage time proceeded. In the samples prepared with CMP, the firmness, adhesiveness, gumminess and chewiness was increased as the storage time proceeded, while springiness and cohesiveness was decreased.

• Journal of the Korea Concrete Institute
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• v.27 no.2
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• pp.127-136
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• 2015

To evaluate the effects of limestone powder and silica fume on the properties of high-strength high-volume ground granulated blast-furnace slag (GGBFS) blended cement concrete, this study investigated the rheology, strength development, hydration and pozzolanic reaction characteristics, porosity and pore size distribution of high-strength mortars with the water-to-binder ratio of 20, 50 to 80% GGBFS, up to 20% limestone powder, and up to 10% silica fume. According to test results, compared with the Portland cement mixture, the high-volume GGBFS mixture had much higher flow due to the low surface friction of GGBFS particles and higher strength in the early age due to the accelerated cement hydration by increase of free water; however, because of too low water-to-binder ratio and cement content, and lack of calcium hydroxide content, the pozzolanic reactio cannot be activated and the long-term strength development was limited. Limestone powder did not affect the flowability, and also accelerate the early cement hydration. However, because its effect on the acceleration of cement hydration is not greater than that of GGBFS, and it does not have hydraulic reactivity unlikely to GGBFS, compressive strength was reduced proportional to the replacement ratio of limestone powder. Also, silica fume and very fine GGBFS lowered flow and strength by absorbing more free water required for cement hydration. Capillary porosities of GGBFS blended mortars were smaller than that of OPC mortar, but the effect of limestone powder on porosity was not noticeable, and silica fume increased porosity due to low degree of hydration. Nevertheless, it is confirmed that the addition of GGBFS and silica fume increases fine pores.

• Journal of Life Science
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• v.22 no.10
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• pp.1407-1414
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• 2012

Hormone replacement therapy (HRT) is an effective regimen that has been found to prevent these diseases in postmenopausal women. However, HRT is accompanied by an increased risk of unfavorable outcomes. This study was conducted to evaluate the effects of Eisenia Bicyclis extract on lipids in ovariectomized rats. Fifty 7-week-old female Sprague-Dawley rats were randomly assigned to four groups: sham-operated rats (SHAM), ovariectomized rats (OVX-CON), and ovariectomized rats that were treated with Eisenia bicyclis extracts. The extract-treated diets were fed to the rats for 6 weeks after operation. Antioxidant effects were measured by DPPH free radical scavenging activity. Antioxidant activity of the ethanol extract increased in a dose-dependent manner and was about 55.9% in a concentration of 100 ${\mu}g/ml$. We measured the total cholesterol content, triglyceride content, HDL-cholesterol content, LDL-cholesterol content, atherosclerotic index, cardiac risk factor in serum, and anti-platelet aggregation and blood rheology. The total cholesterol and triglyceride concentration in serum increased for the OVX-control group, but supplementation with the E. bicyclis extract caused these factors to decrease. Notably, the serum LDL-cholesterol concentration in the OVX-EB200 group was significantly lower than the OVX-CON group. In addition, the blood passage times in rats that received the E. bicyclis extract were more rapid than the times in the untreated group (OVX-CON). Microscopic evaluation revealed that whole blood passed more smoothly through the microchannels in rats in the E. bicyclis extract supplement groups. Our results clarified the effects of E. bicyclis extract on serum lipid content in ovariectomized rats, and consequently we expect positive effects from providing E. bicyclis extract to postmenopausal women with cardiovascular disease.

• Journal of Food Hygiene and Safety
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• v.34 no.5
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• pp.463-472
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• 2019

This study investigated the quality characteristics and antioxidant activities of morning bread containing various amounts of aronia sourdough starter. Morning breads were prepared with different volumes (0% (AS0), 15% (AS1), 25% (AS2), and 35% (AS3)) of aronia sourdough starter based on wheat flour. In AS3 group (35% added group), the specific volume and baking loss rate were the highest but the bread height was the lowest. When the aronia sourdough starter was added up to 25%, the expansion power, specific volume, and bread height were significantly increased (P<0.05). According to the added amount of sourdough starters, the lightness and yellowness of the morning bread were decreased, however, redness was increased (P<0.05). In the rheology analysis, hardness, gumminess, and chewiness were significantly decreased with increasing amounts of aronia sourdough starters (P<0.05). However, cohesiveness was the highest in the AS2 group (25% added group). In consumer preference, the highest scores were shown in AS2 group (25% added group) in color, texture, and appearance. The total polyphenol and DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging ability were both significantly increased along with aronia sourdough content (P<0.05). In conclusion, morning bread with 25% aronia sourdough starter showed the best quality characteristics and antioxidant activities.