• Korean Journal of Food Science and Technology
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• v.50 no.3
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• pp.267-273
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• 2018

Horse fat was extracted from fatty horse meat at $70^{\circ}C$ under vacuum conditions. The oxidative stability of horse fat was investigated by the addition of 0, 30, 60, and 150 mg/kg of ${\alpha}$-, ${\gamma}$-, or ${\delta}$-tocopherol during storage of 14 days at $65^{\circ}C$ in the dark. Changes of tocopherol concentration and fatty acid composition, peroxide value, and 2-thiobarbituric acid (TBA) value were analyzed during storage. The levels of the added tocopherols were found to decrease during storage. Unsaturated fatty acids contents of horse fat without tocopherol decreased from 60.87% to 57.22% after 14 days. The peroxide value and TBA value increased as storage time increased. The peroxide values of horse fat after addition of 0, 30, 60, and 150 mg/kg of ${\gamma}$-tocopherol were 43.75, 25.17, 20.87, and 15.41 meq/kg, respectively, and the TBA values were 7.87, 5.64, 4.43, and 4.23 mg malonaldehyde (MA)/kg, respectively, after 14 days. At the concentration of 150 mg/kg, both ${\gamma}$- and ${\delta}$-tocopherol impeded the oxidation of horse fat during storage.

• Korean Journal of Food Science and Technology
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• v.34 no.4
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• pp.617-624
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• 2002

Health drinks were prepared with freeze dried powder of 60% ethanol extract (60% EFDP), 60% ethanol extract after hydrolysis with amyloglucosidase (60% AEFDP) and 80% ethanol extract (80% EFDP) from roasted safflower seed. Quality characteristics and antioxidative properties were investigated. Yield of freeze dried powders were ranged in $4.67%{\sim}5.62%$. Brix, pH and titratable acidity of safflower drinks were ranged in $11.4{\sim}14.2%$, $2.83{\sim}3.34$ and $0.09{\sim}0.91%$, respectively. Content of total phenolic compounds was much more in 80% EFDP (117 mg/g) and safflower drink-I (SD-I, 440 ppm) than others. Content of total flavonoid was observed in higher level in 60% EFDP (49 mg/g) and safflower drink-V (SD-V, 138 ppm) than others. Antioxidant compounds such as N-[2-(5-hydroxy-1H-indol-3-yl)ethyl]ferulamide(serotonin-I) and N-[2-(5-hydroxy-1H-indol-3yl)ethyl]-p-coumaramide(serotonin-II) exhibited higher contents of 21.09 ppm, 33.56 ppm in 60% EFDP and of 3.83 ppm, 5.81 ppm in safflower drink-II (SD-II) than others. Content of acacetin was much more in 80% EFDP (13.53 ppm) and safflower drink-IV (SD-IV, 1.14 ppm) than others. From the DPPH test to measure antioxidant activity, it was shown that 80% EFDP and SD-I have stronger scavenging activities of 94.58% and 94.88%, respectively, while BHA standard solution does 93.88%. Among drinks, SD-II was revealed to have highest level on overall acceptance, color and flavor through sensory evaluation. These results induced that safflower seed can be used as natural antioxidant and functional food material.

• Korean Journal of Food Science and Technology
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• v.12 no.2
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• pp.115-121
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• 1980

The oils extracted with n-hexane from 6 samples of rapeseed (5 Korean samples and 1 Canadian sample) and samples of rapeseed salad oil at the market in Korea were examined. The physical and chemical characteristics of the oils were determined, and the lipid components of the oils were determined by column, thin layer-and gas liquid chromatography. The results obtained were as follows 1. The average crude fat contents in rapeseed was 43.3 % and the content of Korean was higher than that of Canadian by about 3 %. 2. The average values of specific gravity-, refractive-index, saponification value, iodine value, acid value and nonsaponifiable content of the crude oils extracted from Korean rapeseed were 0.9133, 1.4726, 103.6, 0.51 and 1.17%, respectively. 3. The average content of polar and nonpolar in total lipids were 2.7 % and 97.3 % respectively. Triglyceride was the predominant in nonpolar fraction, averaging 92.7 % of total lipids while sterol esters and diglycerides constituted 1.5 % and 1.2 % of the total. Monoglycerides, free fatty acids and free sterols were minor components of the nonpolar fraction. The polar lipids were primarily phospholipids(1.8%), but a significant amount of glycolipid (0.7%) was also found in each oil. 4. The fatty acid compositions in the total lipids showed the Korean rapeseeds averaged 46.7 % erucic, 15 % oleic, 13.4 % linoleic, 9.3 % eicosenoic and 4.3 % palmitic acids. The Canadian rapeseed, however, contained only 0.7 % of erucic acid. 5. The fatty acid compositions in nonpolar lipid fractions was similar to the pattern in those of the total lipids. But phospholipid and glycolipid fractions were lower in erucic acid content than nonpolar lipid fractions.

• Food Science and Preservation
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• v.25 no.1
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• pp.79-89
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• 2018

In this study, the anti-oxidant, whitening, and anti-wrinkle effects of Castanea crenata inner shell extracts processed by enzyme treatment and pressurized extraction were investigated. The Castanea crenata inner shell was first hydrolyzed using celluclast, viscozyme, or hemicellulase. Then, it was subjected to pressure extraction for different durations (30, 60, and 120 min). The yields of the Castanea crenata inner shell extracts processed by different enzyme treatments followed by pressurized extraction for different times are in the range of 12.42-29.80%. The total polyphenol, flavonoid, and tannin contents of the C30m (celluclast enzyme and autoclave extracts at 30 min) extract were 15.48, 10.82, and 15.82 g/100 g, respectively. The total sugar content of the H120m(hemicellulase enzyme and autoclave extracts at 120 min) extract is 61.07 g/100 g. The 1,1-diphenyl-2-pycrylhydrazyl (DPPH) and 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging activities of the C30m extract at $1,000{\mu}g/mL$ are 89.20, and 81.96%, respectively. The superoxide radical scavenging and ferric-reducing antioxidant power of the C30m extract at $1,000{\mu}g/mL$ are 67.63% and $1,324.79{\mu}M$, respectively. Further, the tyrosinase and elastase inhibition activity of the C30m extract at $1,000{\mu}g/mL$ are 61.32, and 61.06%, respectively. Our results indicate that the Castanea crenata inner shell extracts processed by enzyme treatment followed by pressurized extraction could have beneficial effects on facial skin and they should be considered for use in new functional cosmetics.

• Korean Journal of Plant Resources
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• v.28 no.2
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• pp.263-270
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• 2015

To reduce the injury by continuous cropping system of tomato cultivation, green manure crops (GMCs) such as hairy vetch and rye were applied, Nutrient contributions of N, P₂O₅, K₂O, CaO, and MgO in hairy vetch were 26.2, 5.8, 10.2, 6.6, and 1.5 ㎏/10a, respectively. Nutrient contributions of N, P₂O₅, K₂O, CaO, and MgO in rye were 9.1, 4.2, 11.8, 3.8, and 3.1 ㎏/10a, respectively. After incorporation of GMCs into soil, bulk density in soil with GMCs was lower than that in soil without GMCs (control). In soil after incorporation of GMCs, pH was not different in all treatment conditions, and ranged from 6.37~6.52. EC in soil after incorporation of GMCs was lower than that in soil without GMCs. The OM, T-N, and avail. P₂O₅ contents in soil with GMCs were higher than those in soil without GMCs. The tomato growths were increased in the rotational cropping system (RCS) as compared to continuous cropping system (control and without NPK). Also the density of Pseudomonas corrugata in soil with GMCs was lower than that in soil without GMCs (control). This study suggest that the RCS using GMCs showed lower disease outbreak density in soil for tomato cultivation as compared to RCS without GMCs. Especially, the GMCs was good effect for reduction of continuous cropping injury of tomato.

• 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 Food Hygiene and Safety
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• v.33 no.6
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• pp.466-473
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• 2018

An analytical method of sodium polyacrylate in processed food products was developed and monitored by using size-exclusion chromatography. GF-7M HQ column and UV/VIS detector were selected based on peak shape and linearity. Flow rate, column oven temperature, and mobile phase were selected as 0.6 mL/min, $45^{\circ}C$, and 50 mM sodium phosphate buffer of pH 9.0, respectively. Samples for analysis of sodium polyacrylate were extracted with 50 mM sodium phosphate buffer of pH 7.0 for 3 hr at $20^{\circ}C$ and 150 rpm. Analytical method validation revealed proper selectivity and calibration curve was selected in the range of 50-500 mg/L, and correlation coefficient of calibration curve was more than 0.9985. Limit of detection of sodium polyacrylate was 10.95 mg/kg and limit of quantification was 33.19 mg/kg. Accuracy and coefficient of variation for sodium polyacrylate analysis was 99.6-127.6%, 3.0-8.3% for intra-day and 94.3-121.9%, 1.3-2.6% for inter-day, respectively. Sodium polyacrylate was detected in 40 samples among monitored 125 processed food products. Detected contents were less than 0.2%, limited by the Food Additives Code. Results suggest the established size-exclusion chromatography method could be used to analyze sodium polyacrylate in processed food products.

• Clean Technology
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• v.27 no.1
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• pp.9-16
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• 2021

Since the active matrix organic light-emitting diode (AMOLED) encapsulation process is very vulnerable to moisture and oxygen, high-purity nitrogen with minimal moisture and oxygen must be used. In this study, a copper-based catalyst used to remove oxygen from nitrogen in the AMOLED encapsulation process was optimized. Two-component and three-component catalysts composed of CuO, Al2O3, or ZnO were prepared through a co-precipitation method. The prepared catalysts were characterized by using BET, XRD, TPR, and XRF analysis. In order to verify the oxygen removal performance of the catalyst, several catalytic reactions were conducted in a fixed bed reactor, and the corresponding oxygen contents were measured through an oxygen analyzer. In addition, reusability of the catalysts was proven through repetitive regeneration. The properties and oxygen removal capacity of the catalysts prepared with CuO and Al2O3 ratios of 6 : 4, 7 : 3, and 8 : 2 were compared. The number of active sites of the catalyst with a ratio of CuO and Al2O3 of 8 : 2 was the highest among the 2-component catalysts. Moreover, the reducibility of the catalyst with a ratio of CuO and Al2O3 of 8 : 2 was the best as it had the highest CuO dispersion. As a result, the oxygen removal ability of the catalyst with a ratio of CuO and Al2O3 of 8 : 2 was the best among the 2-component catalysts. The best oxygen removal capacity was obtained when 2wt% of ZnO was added to the sub-optimized catalyst (i.e., CuO : Al2O3 = 8 : 2) probably due to its outstanding reducibility. Furthermore, the optimized catalyst kept its performance during a couple of regeneration tests.

• Korean Journal of Mineralogy and Petrology
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• v.35 no.2
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• pp.153-168
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• 2022

Petrological and mineralogical analyses were conducted to identify minerals containing radioactive elements (uranium) in the Chiaksan gneiss complex and to confirm their association with the surrounding groundwater. Fourteen minerals were identified through the microscopic and electron microscopy (SEMEDS) investigation. The principal minerals included plagioclase, biotite, quartz, alkali feldspar, chlorite, and calcite. Minor minerals were sphene, allanite, apatite, zircon, thorite, titanite, pyrite, and galena. A small amount of thorite was observed in the size of ~1 mm within macrocrystalline allanite. Allanite, which includes a large amount of rare earth elements, appeared in three distinctive patterns. The results of the EPMA analyses indicated that macrocrystalline allanite had higher elemental contents of TiO₂~1.70 wt.%, Ce₂O₃~11.86 wt.%, FeO ~13.31 wt.%, MgO ~0.90 wt.% and ThO₂ ~1.06 wt.% with the lowest average content of Al₂O₃ 17.35 ± 2.15 wt.% (n = 7), CaO 12.13 ± 1.81 wt.% (n = 7). An allanite existing at the edge of the sphenes encompassing titanites had a higher element content of Al₂O₃ ~24.00 wt.%, Nd₂O₃ ~5.10 wt.%, Sm₂O₃~0.66 wt.%, Dy₂O₃~0.86 wt.% and Y₂O₃~1.38 wt.% with the lowest average content of TiO₂ 0.35 ± 0.21 wt.% (n = 11), Ce₂O₃ 5.25 ± 1.03 wt.% (n = 11), FeO 9.84 ± 0.26 wt.% (n = 11), MgO 0.12 ± 0.05 wt.% (n = 11), and La₂O₃ 1.49 ± 0.29 wt.% (n = 11). Allanites in a matrix of parental rocks exhibited intermediate values between the two elemental compositions mentioned above. None of the uranium-rich minerals were observed in the migmatitic gneiss within the study area. Consequently, the origin of uranium in the groundwater was not associated with the geology of the surrounding environment, but our investigation proved the existence of abundant allanites containing significant amounts of radioactive thorium and rare earth elements.

• Food Science and Preservation
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• v.19 no.1
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• pp.12-18
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• 2012

In this study, 0, 20, 40, 60, 80, and 100% $Ulmus$ $pumila$ L. nonglutinous and glutinous sikhe were added to $Ulmus$ $pumila$ L. extracts for 15 days at $4^{\circ}C$, and for seven days at $25^{\circ}C$, to examine the extracts' storage properties and sensory characteristics. The results are as follows: (1) On the changes of pH and acidity during storage of $Ulmus$ $pumila$ L. nonglutinous and glutinous sikhe, both of them showed lower pH values with lower additive $Ulmus$ $pumila$ L. extract contents. The pH value continuously decreased with a longer storage period, and the acidity was higher with a lower concentration of $Ulmus$ $pumila$ L. extract. (2) The total microbial cell count during storage of $Ulmus$ $pumila$ L. nonglutinous and glutinous sikhe at $4^{\circ}C$ was 4.6-5.0 log CFU/g at 0 day. The sikhe to which $Ulmus$ $pumila$ L. extract was not added increased to 8.8-9.0 log CFU/g on the seventh storage day, while the sikhye to which 80 and 100% $Ulmus$ $pumila$ L. extracts were added were 7.8 and 6.9 logCFU/g, respectively. Thus, the total cell count was lower with a higher additive content of $Ulmus$ $pumila$ L. extract. The total cell count of the sikhe to which 0-60% $Ulmus$ $pumila$ L. extracts reached the maximum value on the seventh storage day and did not show any change thereafter. The total cell count of the sikhe to which 80 and 100% $Ulmus$ $pumila$ L. extracts were added, however, reached the maximum value on the 10th to 13th storage days, thus showing that the storage period was increased by $Ulmus$ $pumila$ L. At $25^{\circ}C$, the total cell count was 4.6-5.0 log CFU/g on 0 day and continuously increased during the storage period. It had increased to 8.9-9.5 log CFU/g on the seventh storage day, and no differences were shown according to the additive content of $Ulmus$ $pumila$ L. extract. (3) On the sensory characteristics of $Ulmus$ $pumila$ L. nonglutinous and glutinous sikhe, the $Ulmus$ $pumila$ L. nonglutinous sikhe to which 20% $Ulmus$ $pumila$ L. extract was added showed the highest overall-acceptability value ($4.23{\pm}0.95$), whereas the $Ulmus$ $pumila$ L. glutinous sikhe to which 40% $Ulmus$ $pumila$ L. extract was added showed the highest overall-acceptability value ($3.95{\pm}0.95$). The sikhe to which 20 and 40% $Ulmus$ $pumila$ L. extracts were added showed significantly high taste, flavor, sweetness, and overall-preference values (p<0.05).