• Applied Biological Chemistry
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• v.51 no.1
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• pp.24-37
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• 2008

Yeast with excellent ferment ability was isolated and selected from wild grape to manufacture wild grape wine. Wild grape wine by SMR-3 isolated from wild grape was better than other strains in quality, such as high alcohol content and low acidity, residual sugar, organic acid and fusel oil content. Fermentation condition was optimized to manufacture wild grape wine with response surface methodology using isolated SMR-3 as an alcohol fermentation strain. As a result of culture conditions, 10.61% of alcohol content was expected under the conditions of $21.91^{\circ}C$ fermenting temperature, $21.48^{\circ}brix$ of initial sugar content, and 14.65 day of fermentation time. Residual sugar content showed the lowest value at $24.48^{\circ}C$ fermentation temperature, $12.78^{\circ}brix$ of initial sugar content, and 9.02 day fermentation time. The highest level of sensory evaluation was found at $20.23^{\circ}C$ fermentation temperature, $25.30^{\circ}brix$ of initial sugar content, and 5.94 day fermentation time. Ethyl alcohol was the main alcohol component in wild grape wine and fusel oil in wild grape wine was hardly detected; thus, the quality of wild grape wine was considered excellent. The optimal fermentation conditions of wild grape wine was superimposed by deriving a regression equation for alcohol content, fusel oil, ethyl alcohol content, and overall palatability for each variable of wild grape wine. Hence, the optimal fermentation conditions are estimated to be: fermentation temperature $24{\sim}28^{\circ}C$, initial sugar content $20{\sim}24^{\circ}brix$, and fermenting time $12{\sim}14$ days.

• Food Science and Preservation
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• v.30 no.1
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• pp.132-145
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• 2023

In this study, culture conditions were optimized to confirm the feasibility of Acetobacter pasteurianus as a starter for fermentation vinegar. Acetobacter pasteurianus strain can be used as a food ingredient. The optimal temperature and pH conditions of the selected Acetobacter pasteurianus SRCM101388 were 28℃ and pH 6.00, respectively. The response surface methodology (RSM) was used to optimize the composition of the medium, and Plackett-Burman design (PBD) was used to obtain the effective selection of culture medium, resulting in that glucose, sucrose, and yeast extract had the highest effect on increasing biomass. The optimal concentration, which was performed by central composite design (CCD), were determined to be 10.73 g/L of glucose, 3.98 g/L of sucrose, and 18.73 g/L of yeast extract, respectively. The optimal concentrations of trace elements for the production of biomass were found to be 1 g/L of ammonium sulfate, 0.5 g/L of magnesium sulfate, 2 g/L of sodium phosphate monobasic, 2 g/L of sodium phosphate dibasic, and the final optimized medium was pH 6.10. When incubated in a 5 L jar fermenter, the SRCM101388 strain showed a faster-dissolved oxygen (DO) reduction at a lower agitation rate (rpm), and it was able to grow even at reduced DO level when aeration was maintained. The amount of final biomass produced was 2.53±0.12×10⁹ CFU/mL (9.40±0.02 log CFU/mL) when incubated for 18 hours at 150 rpm, 0.5 vvm, pH 6.0, and 28℃.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.49 no.3
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• pp.301-309
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• 2016

To facilitate the effective use of butter clam shell as a natural calcium resource, we determined the optimal conditions for calcium lactate (BCCL) preparation with high solubility using response surface methodology (RSM). The polynomial models developed by RSM for pH, solubility and yield were highly effective in describing the relationships between factors (P<0.05). Increased molar ratios of calcined powder (BCCP) from butter clam shell led to reduced solubility, yield, color values and overall quality. The critical values of multiple response optimization to independent variables were 1.75 M and 0.94 M for lactic acid and BCCP, respectively. The actual values (pH 7.23, 97.42% for solubility and 423.22% for yield) under optimization conditions were similar to the predicted values. White indices of BCCLs were in the range of 86.70–90.86. Therefore, organic acid treatment improved color value. The buffering capacity of BCCLs was strong, at pH 2.82 to 3.80, upon the addition of less than 2 mL of 1 N HCl. The calcium content and solubility of BCCLs were 6.2–16.7 g/100 g and 93.6-98.5%, respectively. Fourier transform analysis of infrared spectroscopy data identified BCCL as calcium lactate pentahydrate, and the analysis of microstructure by field emission scanning electron microscopy revealed an irregular form.

• Food Science and Preservation
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• v.19 no.5
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• pp.703-711
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• 2012

This study was conducted to investigate the quality and organoleptic properties of dehydrated onions with steaming and heating. Sliced onions were treated as follows: steaming time ($X_1$, 5~25 min); drying temperature ($X_2$, $55{\sim}70^{\circ}C$) and drying time ($X_3$, 4~20 hr). All the variables were modelled and analyzed using a central composite design and response surface methodology (RSM). The coefficients ($R^2$) of the water content and water activity model induced from RSM were 0.9514 (p<0.01) and 0.9455 (p<0.01), respectively. The water content and water activity were affected by the drying temperature and time. The $R^2$ on the models of Hunter's L, a, b values were 0.9419 (p<0.05), 0.8818 (p<0.01) and 0.9360 (p<0.01), respectively. Hunter's L, a, b values were affected by the drying temperature and time, but Hunter's b value was not affected by the steaming time. In addition, the $R^2$ on the models of overall palatability was 0.8867 (p<0.05). The maximum palatability response was 5.92 when the steaming time was 13.14 min, the drying temperature was $63.11^{\circ}C$ and the drying time was 14.49 hr.

• Korean Journal of Food Science and Technology
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• v.30 no.3
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• pp.523-528
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• 1998

Response surface methodology (RSM) was used to monitor extraction characteristics of electron donating ability and organoleptic properties for ethanol extracts from Chrysanthemum petals, thereby determining optimum extraction conditions. A central composite design was applied to investigate effects of solvent per sample $(X_1)$, ethanol concentration $(X_2)$ and extraction time $(X_3)\;at\;60^{\circ}C$ on dependent variables such as electron donating ability $(Y_1)$, organoleptic color $(Y_2)$ and organoleptic aroma $(Y_3)$ of the extracts. Second-order models were employed to generate 4-dimensional response surfaces for qualitative and quantitative aspects of ethanol extracts. Coefficients of determination $(R_2)$ of the models for dependent variables were ranged from 0.8180 to 0.9696. Optimum extraction conditions for each variable were 50 mL/g, 61% and 16 hrs in electron donating ability, 88 mL/g, 21% and 16 hrs in organoleptic color, 55 mL/g, 73% and 19 hrs in organoleptic aroma, respectively. The optimum condition ranges for maximized characteristics of ethanol extracts were $65{\sim}78\;mL/g,\;90{\sim}100%\;and\;15{\sim}25\;hrs$. Predicted values at the optimum conditions were in good agreement with experimental values.

• Food Science and Preservation
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• v.16 no.4
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• pp.472-481
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• 2009

Response surface methodology (RSM) is frequently used for optimization studies. In the present work, RSM was used to determine the antimicrobial activitiesof grapefruit seed extract (GFSE) and a lactic acid mixture (LA) against Staphylococcus aureus, Bacillus cereus, Escherichia coli, Salmonella typhimurium, Pseudomonas fluorescens, and Vibrio parahaemolyticus. A central composite design was used to investigate the effects of independent variables on dependent parameters. One set of antimicrobial preparations included mixtures of 1% (w/w) GFSE and 10% (w/w) LA, in which the relative proportions of component antimicrobials varied between 0 and 100%. In further experiments, the relative proportions were between 20% and 100%. Antimicrobial effects against various microorganisms were mathematically encoded for analysis. The codes are given in parentheses after the bacterial names, and were S. aureus ($Y_1$), B. cereus ($Y_2$), E. coli ($Y_3$), S. typhimurium ($Y_4$), P. fluorescens ($Y_5$), and V. parahaemolyticus ($Y_6$). The optimum antimicrobial activity of the 1% (w/w) GFSE:10% (w/w) LA mixture against each microorganism was obtained by superimposing contour plots ofantimicrobial activities on measures of response obtained under various conditions. The optimum rangesfor maximum antimicrobial activity of a mixture with a ratio of 1:10 (by weight) GFSE and LA were 35.73:64.27 and 56.58:43.42 (v/v), and the optimum mixture ratio was 51.70-100%. Under the tested conditions (a ratio of 1% [w/w] GFSE to 10% [w/w] LA of 40:60, and a concentration of 1% [w/w] GFSE and 10% [w/w] LA, 70% of the highest value tested), and within optimum antimicrobial activity ranges, the antimicrobial activities of the 1% (w/w) GFSE:10% (w/w) LA mixture against S. aureus ($Y_1$), B. cereus ($Y_2$), E. coli ($Y_3$), S. typhimurium ($Y_4$), P. fluorescens ($Y_5$), and V. parahaemolyticus ($Y_6$) were 24.55, 25.22, 20.20, 22.49, 23.89, and 28.04 mm, respectively. The predicted values at optimum conditions were similar to experimental values.

• Food Science and Preservation
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• v.13 no.2
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• pp.252-258
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• 2006

To find the optimum extraction condition of dried omija, central composite experimental design having three independent variable (extraction temperature, extraction time and water ratio) with five levels was conducted for response surface analysis. The maximum of soluble solid was predicted to the extraction conditions of over 25 fold water ratio, $7{\sim}8hr$ and $75^{\circ}C$. Total acid, total phenol, reducing sugar and vitamin C were predicted to respectively 30 fold water ratio, 6 hr, $70^{\circ}C$, 30 fold water ratio, $6{\sim}7\;hrs,\;80^{\circ}C$ and 30 fold water ratio, $6{\sim}8\;hr,\;80^{\circ}C$, 25 fold water ratio, $5{\sim}6hr,\;80^{\circ}C$ extraction condition. Turbidity of extraction condition. Turbidity of extraction condition was 7 over 25 ford water ratio and over $60^{\circ}C$. From the superimposing results of response variables, the optimum extraction condition was predicted 25 folds water ratio, 6 hr and $65{\sim}70^{\circ}C$.

• Korean Journal of Food Science and Technology
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• v.35 no.5
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• pp.884-892
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• 2003

This study was conducted to optimize the water homogenization process of mandarin orange peel for colored rice. Four variables were used to determine the optimum conditions for homogenization speed, time, temperature, and water volume with a five level central composite design and response surface methodology. The process was optimized using the combination of EI and b values of rice coated with water extract of the mandarin orange peel. The effect of water volume was the most significant compared to the other variables on the quality of water homogenate. The regression polynomial model was a suitable (p>0.05) model by lack-of-fit analysis showing high significance. To optimize the process, based on surface response and contour plots, individual contour plots for the response variables were superimposed. The optimum conditions for manufacturing water extract from mandarin orange was with 8,500 rpm homogenization speed, 2.8 min time, $53^{\circ}C$ temperature, and 42 mL water volume with the maximum of restricted variables of EI above 400 and h value above 24.

• Industry Promotion Research
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• v.9 no.1
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• pp.21-29
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• 2024

In the rapidly advancing information society, electronic devices, including smartphones and tablets, are increasingly digitized and equipped with high-performance features such as flexible displays. This study focused on optimizing the manufacturing process for Transparent Conductive Films (TCF) by using the cost-effective conductive polymer PEDOT and transparent substrate PET as alternatives to expensive materials in flexible display technology. The variables considered are production speed (m/min), coating maximum temperature (℃), and PEDOT supply speed (rpm), with surface resistivity (Ω/□) as the response parameter, using Response Surface Methodology (RSM). Optimization results indicate the ideal conditions for production: a speed of 22.16 m/min, coating temperature of 125.28℃, and PEDOT supply at 522.79 rpm. Statistical analysis validates the reliability of the results (F value: 18.37, P-value: < 0.0001, R²: 0.9430). Under optimal conditions, the predicted surface resistivity is 145.75 Ω/□, closely aligned with the experimental value of 142.97 Ω/□. Applying these findings to mass production processes is expected to enhance production yields and decrease defect rates compared to current practices. This research provides valuable insights for the advancement of flexible display manufacturing.

• Journal of Microbiology and Biotechnology
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• v.17 no.12
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• pp.1930-1936
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• 2007

A sequential optimization strategy based on statistical experimental designs was employed to enhance the production of cyclosporin A (CyA) by Tolypocladium inflatum DSMZ 915 in a submerged culture. A 2-level Plackett-Burman design was used to screen the bioprocess parameters significantly influencing CyA production. Among the 11 variables tested, sucrose, ammonium sulfate, and soluble starch were selected, owing to their significant positive effect on CyA production. A response surface methodology (RSM) involving a 3-level Box-Behnken design was adopted to acquire the best process conditions. Thus, a polynomial model was created to correlate the relationship between the three variables and the CyA yield, and the optimal combination of the major media constituents for cyclosporin A production, evaluated using the nonlinear optimization algorithm of EXCEL-Solver, was as follows (g/l): sucrose, 20; starch, 20; and ammonium sulfate, 10. The predicted optimum CyA yield was 113 mg/l, which was 2-fold the amount obtained with the basal medium. Experimental verification of the predicted model resulted in a CyA yield of 110 mg/l, representing 97% of the theoretically calculated yield.