• KSBB Journal
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• v.10 no.4
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• pp.455-460
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• 1995

Specific growth rate was controlled for the repression of acetic acid formation in the fed-batch fermentation of recombinant Escherichia coli. With controlled specific growth rate, we studied the effect of the specific growth rate on cell growth, glucose consumption, acetic acid formation, and the expression of recombinant protein (${\beta}$-lactamase). High specific growth rate caused the accumulation of glucose and acetic acid, and lowered the production of recombinant protein. However, the addition of methionine recovered the gene expression by alleviating the negative effect of acetic acid at high specific growth rate.

• Food Science and Preservation
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• v.18 no.6
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• pp.980-985
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• 2011

This study was conducted to determine the acetic-acid fermentation properties of apple juice (initial alcohol content, apple juice concentration, acetic-acid content, and inoculum size) in flask scale. At the acetic-acid fermentation of apple juice with 3, 5, 7, and 9% initial alcohol content, the maximum acidity after 10-day fermentation was 5.88% when the initial alcohol content was 5%. The acetic-acid fermentation did not proceed normally when the initial alcohol content was 9%. When the initial Brix was $1^{\circ}$, the acidity gradually increased, and the acidity after 12-day acetic-acid fermentation was 4.48%. Above 4% acidity was attained faster when the apple juice concentration was 5 and 10 $^{\circ}Brix$ than when it was 1 and 14 $^{\circ}Brix$. When the initial acidity was 1% or above (0.3, 0.5, 1.0, and 2.0%), the acetic-acid fermentation proceeded normally. The acetic-acid fermentation also proceeded normally when the inoculum sizes were 10 and 15%, and the acidity after eight-day acetic-acid fermentation was 5.60 and 6.05%, respectively. Therefore, the following were considered the optimal acetic-acid fermentation conditions for apple cider vinegar: 5% initial alcohol content, 5 $^{\circ}Brix$ or above apple juice concentration, 1.0% or above initial acidity, and 10% or above inoculum size. Apple cider vinegar with above 5% acidity can be produced within 48 h under the following acetic-acid fermentation conditions: 7% initial alcohol content, about 1% initial acidity, and 10% inoculum volume at $30^{\circ}C$, 30 rpm, and 1.0 vvm, using 14 $^{\circ}Brix$ apple juice in a mini-jar fermentor as a pre-step for industrial-scale adaptation.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.8 no.3
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• pp.431-434
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• 1998

Layered basic copper acetate, $Cu(OH)(CH_3COO){cdot}H_2O$ was synthesized. Intercalation compounds of alkyl sulfonates into layered basic copper acetate have been synthesized via anionic exchange. From the X-ray diffraction data and the alkyl sulfonate size, the orientation of the intercalated alkyl sulfonate into layered basic copper acetate was determined.

• KSBB Journal
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• v.9 no.5
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• pp.492-498
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• 1994

A hollow fiber device was utilized to perform a dialysis culture for E. coli. Acetic acid inhibition on the growth of E. coli was relieved by dialyzing the acid from broth into a dialysate reservoir. The rate of acetic acid formation was very sensitive to the concentration of glucose and dissolved oxygen. Therefore it was found that the glucose permeation rate should be balanced with the oxygen supply rate. Specific growth rate of E. coli was determined by the glucose permeation rate through membrane. Under a low permeation rate, acetic acid formation was depressed in accordance with high dissolved oxygen concentration as well as low glucose concentration.

• Culinary science and hospitality research
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• v.21 no.6
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• pp.255-263
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• 2015

This study was conducted to test the fermenting of high quality vinegar using Wasabi japonica Matsum leaves. Alcohol fermentation with Wasabi japonica Matsum leaves resulted in the reduction of sugar and sugar alcohol content during fermentation, which decreased sharply over 3 days. The alcohol content was maximized (15.4%) after 8-days of alcohol fermentation at $27^{\circ}C$ by adjusting the initial sugar concentration to $27^{\circ}Brix$, and vinegar with an acidity of 5.1% was obtained after 21-days of acetic acid fermentation at $30^{\circ}C$. The pH was shown to be 3.5 after 21-days of acetic acid fermentation at $30^{\circ}C$. Regarding the color of Wasabi japonica Matsum leaves vinegar, the L and b values increased according to fermentation time, whereas a color values decreased. In conclusion, based on the above results, it is determined that the use of Wasabi japonica Matsum leaves allows for the production of high-quality vinegar.

• Microbiology and Biotechnology Letters
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• v.48 no.1
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• pp.90-97
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• 2020

Vinegar was prepared from corn produced in Gangwon province and changes to the major aroma components were investigated for acetic acid fermentation and ripening. The most prevalent volatile component in corn alcohol was determined to be 2-phenylethanol (accounting for 27% of total aroma components); the levels of 2-phenylethanol decreased to 15% after acetic acid fermentation. Principal component analysis of volatile compounds revealed that corn vinegar was distinguishable from corn alcohol. The highest content of total volatile components (50%) was acetic acid, followed by 2-phenylethanol and diethyl succinate. Ethyl phenylacetate and diethyl succinate had the highest odor activity value, and might contribute most profoundly to the aroma of corn vinegar.

• Food Science and Preservation
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• v.6 no.2
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• pp.228-232
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• 1999

Total acidities were incereased gradually during fermentation. Total acidities of vinegars which fermented from sweet and astringent persimmon were 5.95 and 5.81% at 8th day of acetic acid fermentation, respectively. Hunter's color values were not significant difference during alcohol fermentation and acetic acid fermentation. Browning incereased continuously during alcohol fermentation whereas browning and turbidity decreased continuously during acetic acid fermentation. The browning and turbidity of vinegar which fermented from sweet persimmon was higher than those of vinegar which fermented from astringent persimmon. The contents of total tannin were 2.40 and 6.44mg/ml at the initial fermentation of sweet and astringent persimmon respectively. But in contents decreased continuously during fermentation. Reducing and total sugar contents decreased continuously during fermentation. At 5th day of acetic acid fermentation, contents of reducing and total sugar were 5.0 and 8.5mg/ml in sweet persimmon and 2.8 and 2.9mg/ml in astringent persimmon respectively.

• Resources Recycling
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• v.13 no.6
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• pp.43-48
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• 2004

For the separation of neodymium from NdFeB permanent magnet scrap, the scrap was roasted for oxidizing, and leached with acetic acid followed by fractional crystallization for selective separation. From the analysis results of the leached solution, the optimum condition for the recovery of neodymium was found that leaching temperature, leaching time and pulp density are 80$^{\circ}C$, 3 hours, and 35%, respectively. At this optimum condition, more than 90% of neodymium could be recovered. Concentration of neodymium acetate in acetic acid. The optimum condition for the recovery of neodymium acetate crystal from the leached solution was that the initial leaching solution was evaporated until the remaining volume was about 1/5 of the initial volume. At this condition, 67.5% of neodymium was recovered from the leached solution. The neodymium remaining in the concentrated solution was recovered by reacting it with oxalic acid.

• Food Science and Preservation
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• v.13 no.3
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• pp.357-362
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• 2006

In other to produce vinegar min citron (Citrusu junos), acetic acid bacteria were selected from several conventional vinegars, and total 25 acetic acid producing bacterial strains were isolated. Among the isolated strains, a strain was selected from the medium which showed the highest productivity of acetic acid. The strain was identified as Acetobacter sp V-16 and it cultural characteristics were also investigated in the medium with citron juice. Optimum temperature for the growth of Acetobacter sp. V-16 was $30^{\circ}\C$. The medium containing 2% acetic acid, 5% ethanol, and 30% citron juice was suitable for acetic acid production with Acetobacter sp. V-16. The acidity of culture medium was reached to 6.8% after 10 days shaking cultivation at $30^{\circ}\C$.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.7
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• pp.1048-1052
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• 2011

This study examined the flow properties, paste clarity, freeze-thaw stability and gel strength of acetylated sweet potato starch (ASPS) pastes and gels as a function of degree of substitution (DS). ASPS showed high shear-thinning flow behaviors with high Casson yield stress ($\sigma_{oc}$). Consistency index (K), apparent viscosity ($\eta_{a,100}$) and $\sigma_{oc}$ values of ASPS increased with an increase in DS. In the temperature range of $25{\sim}70^{\circ}C$, ASPS followed an Arrhenius temperature relationship. The activation energies (Ea=13.2~14.3 kJ/mol) of the ASPS samples were much lower than that (18.1 kJ/mol) of the native sweet potato starch (SPS). ASPS gels showed better freeze-thaw stability with a significant decrease in syneresis (%) compared to SPS gel. The gel strength values of ASPS were much lower than that of SPS, and significantly decreased with an increase in DS. The clarity of native SPS paste increased after acetylation.