• Food Science of Animal Resources
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• v.38 no.5
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• pp.995-1007
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• 2018

Changes in the physicochemical properties of ready-to-feed liquid infant formula (LIF) stored at different temperatures (10, 20, 30, and $40^{\circ}C$) for 6 mon, focusing on 5-hydroxymethylfurfural (HMF) content, color, pH, fat globule size distribution, and rheological properties were determined. The HMF content increased with storage time, and LIF stored at $40^{\circ}C$ had a higher HMF content than that of LIF stored at $10^{\circ}C$. The lightness ($L^*$) decreased while redness ($a^*$) and yellowness ($b^*$) increased with increasing HMF content. The fat globule size and pH of LIF stored at $10^{\circ}C$ did not change. However, in the case of LIF stored at $30^{\circ}C$ and $40^{\circ}C$, the fat globule size increased and the pH decreased during storage for 6 mon. LIF stored at $40^{\circ}C$ had a higher apparent viscosity (${\eta}_{a,10}$) than that of LIF stored at $10^{\circ}C$, and the shear-thinning behavior of LIF stored at higher temperature was stronger than that of LIF stored at low temperature. The physicochemical changes of LIF during storage were accelerated by Maillard reaction (MR) at higher storage temperatures. Therefore, even if LIF is aseptically manufactured, we recommend that sterilized LIF should be stored at low temperature in order to minimize quality changes during storage.

• Korean Journal of Food Science and Technology
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• v.40 no.6
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• pp.721-725
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• 2008

Changes in the physicochemical and sensory characteristics of the uncooked food, Codonopsis lanceolata saengsik, were investigated to determine an efficient drying method, one of the most important manufacturing processes in the preparation of C. lanceolata saengsik. No changes in the proximate compositions of all samples were observed during hot-air drying at 50 and $60^{\circ}C$ and freeze-drying. The L value in the freeze-dried sample was higher than that in the hot-air dried samples, whereas the b value in the freeze-dried sample was reduced. Dietary fiber content in the hotair dried samples were higher than that in the freeze-dried sample, whereas the total phenolic compounds and crude saponin contents were lower than those in the freeze-dried sample. The highest overall acceptability values in the sensory test for color, flavor, taste, and overall acceptability were 5.63, 5.45, 5.75, and 5.85, respectively. In conclusion, the freezedrying method was the most favorable of the tested method for the manufacture of C. lanceolata saengsik.

• Food Science and Preservation
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• v.9 no.2
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• pp.148-153
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• 2002

Effect of the thickness of low density polyethylene(LDPE) Film as packaging material on changes in physicochemical characteristics of mature-green mume (Prunus mume Sieb. et Zucc) fruits during storage at different temperatures(0, 10 and 25$\^{C}$) were investigated. Fruit samples stored in pouches with 30㎛ thickness of LDPE film maintained well not only external qualities such as Shape and firmness, but also internal chemical properties such as pH, acidity, the content of soluble solid and chlorophyll, and color, comparing with samples stored without packaging material or in other pouches with different film thickness(20 and 40㎛). From the results, it was found that the maintenance of quality of mature-green mume fruits during storage at 0, 10 and 25$\^{C}$ closely related to the changes in respiratory conditions for fruits affected by the film thickness of the packaging material.

• Journal of the Korean Society of Food Science and Nutrition
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• v.27 no.2
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• pp.214-219
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• 1998

This study was carried out to investigate the changes of physicochemical and sensory characteristics according to cold storage period of the vacuum-time beef loin. The pH was decreased for 10 days, and then was increased gradually during storage time. The lactic acid content during the initial storage was 483mg/100g, after storage for 10 days it was increased significantly (p<0.05) to 625mg/100g, and then was decreased with storage time. Regarding of color difference, the L values were 41.0~42.5, but after storage for 40 days they were increased significantly(p<0.05) to 46.2, the a and b values wee 17.3~14.3 and 7.2~5.8, respectively, they were no significant differences depending n storage time. The shear force values showed 584 and 560g for 0 and 10 days, respectively but after storage for 20 days it was decreased significntly(p<0.05) to 299g. The myofibrillar protein extractability was no significant difference for 20 days, howener, it was increased remarkably at 30 days(p<0.05). The myofibrillar fragmentation index was increased significantly (p<0.05) on 20 and 40 days, and the Mg-ATPase activity of myofibrils was increasd to 30 days. The free amino acid was increased during storage periods. The composition of amino acid was composed of glutamic acid, alanine, valine and lysine, which were predominant amino acids as 45%. The total free amino acid was increased 182.18mg/100g to 40 days. The raw meat aroma showed no significant changes during storage time, but the tenderness was increased until 30 days(p<0.05). The color was superior from 20 to 30 days. The taste of cooked meat indicated significant changer to 30 days, but was significantly inferior(p<0.05) at 40 days, the aroma was superior until 30 days(p<0.05). The palatability was superior between 20 and 30 days.

• Korean Journal of Soil Science and Fertilizer
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• v.46 no.3
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• pp.173-181
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• 2013

Livestock wastes are considered as major environmental pollutants because they contain high concentration of organic materials. In 2001, The Environmental Department reported that stock farmers were increasing as 5.1%/year, which resulted in a gradual increase in livestock wastes generation. The direct disposal of livestock wastes create several environmental problems. Thus, several countries banned the disposal of livestock wastes in environment including aquatic systems. Recently, aeration-based liquid fertilization was considered as potential way for the disposal of livestock wastes. In this study, next generation sequencing (NGS) analysis was used to understand the microbial community changes during liquid fertilization of livestock wastes. Microbial community was compared with liquid fertilizer physicochemical analysis such as $BOD_5$, $COD_{Mn}$ pH, N (Nitrogen), P (Phosphorus), K (Potassium) etc. The physicochemical parameters and bacterial community results pave the way for producing effective livestock-based fertilizer. By comparing the physical characteristics of the manure with microbial community changes, it is possible to optimize the conditions for producing effective fertilizer.

• Journal of Ginseng Research
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• v.38 no.2
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• pp.146-153
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• 2014

A systematic comparison of the physicochemical properties of white ginseng (WG), extruded white ginseng (EWG), red ginseng (RG), and extruded red ginseng (ERG) was performed. The aim of the present study was to identify the effects of the physicochemical properties of ginseng by extrusion cooking. The highest value of the water absorption index (WAI) was 3.64 g/g obtained from EWG, and the highest value of the water solubility index (WSI) was 45.27% obtained from ERG. The ERG had a better dispersibility compared with other samples. Extrusion cooking led to a significant increase in acidic polysaccharide and total sugar content but resulted in a decrease in crude fat and reducing sugar contents. Enzyme treatment led to a sharp increase in acidic polysaccharide content, especially the cellulose enzyme. Extrusion cooking led to a significant increase in 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity and reducing power, and the increases in WG and RG were 13.56% (0.038) and 3.56% (0.026), respectively. The data of this study provide valuable information about the effects of extrusion on quality changes of EWG and ERG.

• The Korean Journal of Community Living Science
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• v.25 no.4
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• pp.601-608
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• 2014

This study evaluates changes in yogurt with Ulmus davidiana var. japonica (U. davidiana) in terms of its physicochemical, microbial, and sensory properties during storage. The pH value and mean microbial counts of this yogurt with 0.2 to 0.8% of U. davidiana added ranged from 4.1 to 4.3 and from $1.4{\times}10^8$ to $2.3{\times}10^8cfu/mL$, respectively, during storage at $7^{\circ}C$ for 16 d. In terms of its color, the L value was significantly higher in the control and U. davidiana yogurt 0.2 to 0.4% up to 4 d, than other yogurt samples, and the b value was influenced by the addition of U. davidiana over 0.6% throughout the storage. According to a sensory test, there was a significant difference in the yellowness score between U. davidiana yogurt and the control, but earthy, and bitterness, and viscosity scores were similar. Overall acceptability was not significantly influenced after 8 d of storage in all yogurt samples, including the control. According to these results, concentrations (0.2 and 0.4%) of U. davidiana yogurt had no significantly adverse effects on its physicochemical, microbial, and sensory properties.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2001.04a
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• pp.172-181
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• 2001

Upflow anaerobic sludge blanket (UASB) system employs granular sludge to treat various wastewaters including landfill leachate. CH$_4$ production of the granules determines overall performance of a UASB reactor. Sludge granules are developed by self-granulation of microorganisms and dynamic balance between granule growth and decay results in coexistence of granules with different sizes in the reactor. In this study, granules taken from a laboratory-scale UASB reactor were classified into 4 groups based on their diameters and their Physicochemical characteristics we were investigated. Each group was analyzed for settling ability, specific methanogenic activity (SMA), and elemental content. Settling ability was proportional to granule diameter. suggesting effective detainment of larger granules in the reactor. When acetate or glucose was used as a substrate, all groups showed relatively slight difference in SMA. However SMA with a volatile fatty acid mixture showed significant increase with granule diameter, suggesting better establishment of syntrophic relationship in larger granules. Larger granules showed higher value of SMA upon environmental changes (i.e., PH, temperature, or toxicant concentration). Comparative analysis of elemental contents showed that content (dry weight %) of most tested elements (iron, calcium, phosphorus, zinc, nickel. and manganese) deceased with granule diameter, suggesting importance of these elements for initial granulation. Taken together, this study verified experimentally that Physicochemical Properties of granules are related to granule size distributions. Overall results of physicochemical characterization supports that larger.

• Journal of Ecology and Environment
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• v.31 no.1
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• pp.23-29
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• 2008

The effectiveness of rehabilitation programs for coal mining spoils in Samcheok, Jeongsun, and Mungyung were evaluated based on the physicochemical properties of soil in the rehabilitated areas. These spoils were reclaimed by introducing plants such as black locust (Robinia pseudoacacia), pitch pine (Pinus rigida), birch (Betula platyphylla var. japonica), alder (Alnus hirsuta), bush clover (Lespedeza cyrtobotrya), and grass (Lolium perenne) in planting beds covered with forest soil. In the surface soil, the pH, organic matter, total N, available P, and exchangeable Ca showed significant changes over the years after reclamation. The pH and exchangeable Ca content decreased exponentially over time, whereas organic matter increased linearly and total N and available P increased exponentially. Changes in the physicochemical properties of subsurface soils displayed a different pattern. There were significant changes over time in the organic matter, available P, and exchangeable Ca and Mg contents of the soil. Organic matter increased logarithmically with years since rehabilitation and available P increased exponentially. Meanwhile, exchangeable Ca decreased exponentially, and Mg decreased logarithmically. The changes in the subsurface soil were not as dramatic as those in the surface soil. This result suggests that the ameliorating effects of the establishment and growth of plants more pronounced on the surface soil layer. Stand ordination data showed different relationships with time since rehabilitation in the early and later stages of the rehabilitation process. In the early stages of rehabilitation, stands tended to be arranged in the order of reclamation age. However, in the later stages, there was not a clear relationship between reclamation age and vegetation characteristics. This result suggests that soil amelioration is required for the early stages, after which an autogenic effect becomes more prominent as the vegetation becomes better established.

• Korean Journal of Food Science and Technology
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• v.32 no.3
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• pp.634-639
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• 2000

This study was done to determine the changes in physicochemical components focused on the general compositions, pH, titratable acidity, organic acids, color and sugars during the microwave roasting of cocoa mass and to compare the changes with those during a conventional roasting. The cocoa mass was microwave-roasted at 110 to $150^{circ}C$ and for 10 to 40 min or conventionally roasted at $140^{circ}C$ for 30 min. General compositions of microwave-roasted cocoa mass were not different from those of raw cocoa mass or conventionally-roasted one. The pH changes did not affect the changes in titratable acidity or organic acids. Titratable acidity was different among the three samples. Microwave-roasted cocoa mass showed less sufficient effects on removing organic acids and less changes in color. Fructose, glucose and maltose decreased during a roasting but sucrose showed little changes.