• Korean Journal of Food Science and Technology
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• v.30 no.5
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• pp.1163-1168
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• 1998

Fish tissues were spiked with organophosphorus pesticides (OPPs), mixed with a celite as a drying agent, and dynamically extracted with pure $CO_2$ or modified $CO_2$ for 10 min at different extraction temperatures, pressures and $CO_2$ flow rates. Recoveries of OPPs spiked in jacopever increased with the decrease of extraction temperature and pressure, and decreased with the increase of $CO_2$ flow rates. Modified $CO_2$ extractions with 10% methylene chloride showed a slight increase in the recoveries over pure $CO_2$ extraction. Quantity of fish tissues had great effect on their extraction efficiencies. Recoveries of OPPs were $66.7{\sim}86.3%$ for jacopever, $56.2{\sim}79.2%$ for yellow tail, $57.6{\sim}77.8%$ for blanquillo, $84.2{\sim}96.3%$ for sardine, $74.6{\sim}83.6%$ for mackerel. Application of supercritical carbon dioxide extraction offers an attractive alternative to the use of organic solvents for extraction of pesticide residues from fish tissues.

• Korean Chemical Engineering Research
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• v.43 no.1
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• pp.110-117
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• 2005

In this work, solid-state inclusion complex powders of itraconazole and $2-hydroxypropyl-{\beta}-cyclodextrin(HP-{\beta}-CD)$ were produced by a supercritical anti-solvent (SAS) process. In order to evaluate the degree of complexation, the thermal behavior of the microparticulate complexes was investigated using differential scanning calorimetry. The experimental results obtained for the solubility and dissolution rate of the microparticulate inclusion complexes in a buffer solution of pH 1.2 showed that the complexation of itraconazole with $HP-{\beta}-CD$ results in a significant increase in the solubility and dissolution rate of itraconazole. The particle size of the SAS-produced inclusion complexes was dramatically reduced ($<0.1-0.5{\mu}m$) compared with untreated itraconazole ($30-50{\mu}m$) and $HP-{\beta}-CD$ ($50-100{\mu}m$). The solubility of itraconazole was increased with the increase of pressure at a constant temperature to ca. $758.6{\mu}g/mL$ in an aqueous medium of pH 1.2. The dissolution rate of itraconazole was observed to be significantly improved and about 90% of itraconazole was found to be dissolved within 5-10 min.

• Clean Technology
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• v.18 no.2
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• pp.191-199
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• 2012

In order to reduce or remove off-flavor and volatile organic compounds (VOCs) from Laminaria japonica effectively, continuous treatment process by supercritical carbon dioxide (SC-$CO_2$) was applied. After freeze-drying, Laminaria japonica powdered with $710{\mu}m$ was used. Experiments were carried out at temperature range from 35 to $55^{\circ}C$, and pressure range from 10 to 25 MPa for evaluation of SC-$CO_2$ treatment effect. Flow rate of carbon dioxide used in this reseach was constantly fixed at 26.81 g/min. Before and after treatment of SC-$CO_2$, off-flavor and VOCs from Laminaria japonica were analyzed by gas chromatography-mass spectrometry detector (GC-MSD). Total 47 VOCs emitted from Laminaria japonica were identified before treatment of SC-$CO_2$, major components of seaweed smell (ordor) in Laminaria japonica were identified as alcohols, aldehydes, ester and acids, ketone, halogenated compounds and hydrocarbon. Off-flavor and VOCs in all experimental conditions was reduced or removed after SC-$CO_2$ treatment. Among the experimental conditions, the highest removal yield was at 25 MPa and $55^{\circ}C$.

• Clean Technology
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• v.17 no.3
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• pp.266-272
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• 2011

Anchovy oil was extracted using supercritical carbon dioxide ($SCO_2$) and organic solvents. Extraction was carried out at temperature range from 40 to $60^{\circ}C$, and pressure range from 15 to 25 MPa. The flow rate of $CO_2$ (22 $gmin^{-1}$) was constant entire the extraction period of 1.5 h. The fatty acid composition of anchovy oil was analyzed by gas chromatography (GC). The main fatty acids of anchovy oil were myristic acid, palmitic acid, stearic acid, palmitoleic acid, EPA (eicosapentaenoic acid), and DHA (docosahexaenoic acid). In addition, the oil obtained by $SCO_2$ extraction contained a higher percentage of polyunsaturated fatty acids especially EPA and DHA comparing to the organic solvent extracted oil. The oxidative stability of oils extracted from Anchovy by $SCO_2$ extraction was compared to those extracted by organic solvents. Results showed that the storage periods of oils obtained by $SCO_2$ extraction were longer than those of organic solvents extraction.

• Journal of the Korean Recycled Construction Resources Institute
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• v.9 no.1
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• pp.33-40
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• 2021

The objective of this work is to prove a possibility of void f illing through a carbonation f or the purpose of improving the quality of recycled aggregate. Carbonation can permanently immobilize CO2, which is a greenhouse gas, and thus provides additional benefit on environment. In this work, recycled fine aggregate was reacted using gaseous CO2 and supercritical CO2(scCO2) in a closed chamber, and the changes in physical properties of the recycled f ine aggregate bef ore and af ter carbonation were analyzed using the apparent density, skeletal density, pH, and FE-SEM measurements. Thereafter, a mortar specimen was prepared and a compressive strength was measured. According to the experimental results, it was found that the increase in the apparent density and the true density was higher by the reaction with scCO2, which was conducted at high temperature and high pressure compared to the reaction with gaseous CO2. In addition, the pH of the eluted water was found to have a larger initial decrease than that observed with samples from reaction by gaseous CO2. The shape and amount of calcium carbonate crystals were also found to be larger than that from gaseous CO2. The increase in compressive strength was the largest when using recycled fine aggregate reacted with scCO2. It was clear that quality improvement of recycled fine aggregate was higher with scCO2 than with gaseous CO2.

• Textile Coloration and Finishing
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• v.34 no.2
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• pp.93-101
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• 2022

In this study, the dyeing properties of supercritical fluid dyed cotton fabrics were investigated which use two types of dyes, such as C.I. Disperse orange and C.I. Disperse red 167. Dyeing temperature, pressure and leveling time were equally applied at 130 ℃, 250 bar, and 60 minutes with reference to the related literature, and experiments were performed at concentrations of 0.04, 0.1, 0.4 and 0.8 % o.w.f with different concentrations. Dyeability was confirmed through measurement of washing fastness and color coordinate, and a calibration curve of each dye was drawn up and the absorbance of the residual dye was measured to confirm the amount of residual dye and the dye exhaustion rate at the corresponding concentration. As a result of color difference measurement, as the concentration increased, the L^* value decreased and the K/S value increased. However, as the concentration increased, the increase in K/S value decreased compared to the input amount, and this tendency was more obvious in C.I. Disperse red 167 than in C.I. Disperse orange 155. The dye exhaustion rate which was calculated by using the amount of residual dye in the pot was also C.I. Disperse orange 155 was 96.16 % and C.I. Disperse red 167 was 94.57 %. However, as the dyeing concentration increased, the dye exhaustion rate decreased, that C.I. Disperse orange was 95.33 % and C.I. Disperse red 167 was 90.63 %. As a result of the washing fastness test for both dyes, dyed samples of which concentrations were 0.4 and 0.8 % o.w.f decreased by 0.5 ~ 1.0 grade. This is predicted because the dye did not completely adhere to the amorphous region of the cotton fiber and the dye simply adsorbed. The fastness to rubbing also maintained at least grade 3-4 up to the 0.1 % o.w.f concentration, but at the concentration of 0.4 % o.w.f or higher, it fell to grade 1 or lower, showing a very poor friction fastness.

• Clean Technology
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• v.16 no.3
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• pp.191-197
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• 2010

Repair reaction of plasma damaged porous methyl doped SiOCH films was carried out with silylation agents dissolved in supercritical carbon dioxide ($scCO_2$) at various reaction time, pressure, and temperature. While a decrease in the characteristic bands at $3150{\sim}3560cm^{-1}$ was detectable, the difference of methyl peaks was not identified apparently in the FT-IR spectra. The surface hydrophobicity was rapidly recovered by the silylation. In order to induce effective repair in bulk phase, the wafer was heat treated before reaction under vacuum or ambient condition. The contact angle was slightly increased after the treatment and completely recovered after the subsequent silylation. Methyl groups were decreased after the plasma damage, but their recovery was not identified apparently from the FT-IR, spectroscopic ellipsometry, and secondary ion mass spectroscopy analyses. Furthermore, Ti evaporator was performed in a vacuum chamber to evaluate the pore sealing effect. The GDS analysis revealed that the open pores in the plasma damaged films were efficiently sealed with the silylation in $scCO_2$.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.12
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• pp.1847-1855
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• 2015

Supercritical carbon dioxide ($SC-CO_2$) treatment has been becoming an important method for substituting the use of organic solvents for samples extraction prior to analysis due to its low toxicity, ease of handling, low cost of disposal etc. Freeze-dried bovine liver was treated with $SC-CO_2$ under different pressures (200, 300, and 450 bar) in order to investigate effects on physicochemical properties and reduction of microbial load. The yield of lipid extraction from bovine liver by $SC-CO_2$ treatment increased with increasing pressure, with values of 84, 86, and 90% in response to 200, 300, and 450 bar, respectively. Results of high performance liquid chromatography analysis showed that vitamin A and coenzyme $Q_{10}$ ($CoQ_{10}$), which is soluble in lipid, were almost removed from bovine liver by $SC-CO_2$ treatment. Saturated fatty acids ratio of bovine liver decreased with increasing pressure, whereas polyunsaturated fatty acids increased with increasing pressure. Total content of amino acids in bovine liver treated by $SC-CO_2$ was less than that of the control sample without treatment. The number of aerobic bacteria in bovine liver, which was stored at $5^{\circ}C$ for 5 days and freeze-dried, decreased from 6.2 to 4.2 log CFU/g by $SC-CO_2$ treatment at 100 bar for 3 h. Interestingly, coliform bacteria were not found in the bovine liver sample by $SC-CO_2$ at 100 bar for 3 h under all storage conditions. This indicates that $SC-CO_2$ treatment can effectively reduce coliform bacteria in the food matrix even at low moisture. In conclusion, freeze-dried bovine liver by proper $SC-CO_2$ treatment may be used as a potential high protein source, with increasing microbial safety and stability of lipid oxidation.

• Food Science of Animal Resources
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• v.32 no.5
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• pp.644-651
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• 2012

We have investigated the effect of lard fraction extracted with supercritical carbon dioxide (SC-$CO_2$) on the flavor enhancement of maillard reaction product (MRP) based meat flavors. MRP based meat flavors were prepared with low glutamic acid (Glu) hydrolyzed wheat gluten (NaCl concentration: 7.61%(w/v)), ribose, cysteine, garlic juice powder, protease-digested Lentinus edodes powder and lard fractions extracted with SC-$CO_2$. Lard was extracted with SC-$CO_2$ at each of three temperatures (40, 60, and $80^{\circ}C$) and at each of four pressures (30, 40, 50, and 60 MPa). Obtained lard SC-$CO_2$ fractions and MRP based meat flavors with those fractions were analyzed for their total yield, aroma pattern by SMart nose system, and sensorial properties. The extraction yield had no difference as temperature increased from $40^{\circ}C$ to $60^{\circ}C$ and even decreased at $80^{\circ}C$. However, increase in pressure level at $40^{\circ}C$ drastically increased the extraction yield. The aroma patterns of raw lard and lard SC-$CO_2$ fractions with 30 MPa were significantly discriminated from those of SC-$CO_2$ lard fractions extracted with higher pressure by SMart nose system. Aroma pattern of MRP based meat flavors with higher pressure extracted lard fractions also showed significant difference through pattern analysis by the SMart nose system. The MRP based meat flavor with lard SC-$CO_2$ fractions at 50 and 60 MPa were described as less sulfuric, less pungent, and more balanced in roasted meat and sweet attributes from sensory evaluation.

• Korean Journal of Food Science and Technology
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• v.28 no.3
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• pp.411-416
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• 1996

Supercritical fluid extraction of ${\beta}$-carotene from carrot was optimized to maximize ${\beta}$-carotene (Y) extraction yield. A central composite design involving extraction pressure ($X_1$ 200-,100 bar), temperature ($X_2,\;35-51^{\circ}C$) and time ($X_1$$ 60-200min) was used. Three independent factors ($X_1,\;X_2,\;X_3$) were chosen to determine their effects on the various responses and the function was expressed in terms of a quadratic polynomial equation,$Y={\beta}_0+{\beta}_1X_1+{\beta}_2X_2+{\beta}_3X_3+{\beta}_11X_12+{\beta}_22X_3^2+{\beta}_-12X_1X_2+{\beta}_12X_1X_2+{\beta}_13X_1X_3+{\beta}_23X_2X_3,$ which measures the linear, quadratic and interaction effects. Extraction yields of ${\beta}$-carotene were affected by pressure, time and temperature in the decreasing order, and linear effect of tenter point (${\beta}_11$) and pressure (${\beta}_1$) were significant at a level of 0.001(${\alpha}$). Based on the analysis of variance, the model fitted for ${\beta}_11$-carotene (Y) was significant at 5% confidence level and the coefficient of determination was 0.938. According to the response surface of ${\beta}$-carotene by cannoical analysis, the stationary point for quantitatively dependent variable (Y) was found to be the maximum point for extraction yield. Response area for ${\beta}$-carotene (Y) in terms of interesting region was estimated over $10,611{\mu}g$ Per 100 g raw carrot under extraction.