• Food Science and Biotechnology
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• v.17 no.3
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• pp.637-641
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• 2008

This study investigated the heat stability of L-ascorbic acid (AA) in acetic acid solution. To analyze the degradation of AA using high performance liquid chromatography (HPLC), AA was measured at a wavelength of 244 nm in acetic acid and 265 nm in distilled water. During the storage of AA in acetic acid or distilled water at $37^{\circ}C$, degradation of AA was slower in acetic acid than in distilled water. On examining various ratios of AA to acetic acid, the stability of AA at $100^{\circ}C$ for 30 min was the highest when the concentration of acetic acid was 10 times higher than the concentration of AA. After acetic acid was added into AA degraded by heating, the AA is stabilized by reheating. Ultimately, these results indicate that degraded AA is reduced by hydrogen ions dissociated from acetic acid, and the rate of reduction of degraded AA in acetic acid solution is improved with heat processing.

• Korean Journal of Food Science and Technology
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• v.28 no.4
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• pp.756-761
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• 1996

Influence of acetic acid on xylitol production from xylose using Candida parapsilosis KFCC 10875 was investigated at the different concentrations of acetic acid. Acetic acid was totally consumed below 1.0 g/l of its concentration, whereas partially consumed above 3.0 g/l and remained in the medium during xylitol fermentation. Cell growth, xylose consumption, and xylitol production decreased when acetic acid concentration was increased. Specific growth rate of cell and specific consumption rate of xylose also decreased with increasing the concentration of acetic acid. However, the xylitol yield from xylose and specific production rate of xylitol were maximum at 1.0 g/l of acetic acid. The inhibitory effect of acetic acid on xylitol fermentation increased when pH was decreased.

• KSBB Journal
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• v.10 no.4
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• pp.370-373
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• 1995

The major by-products in ethanol fermentation by Saccharomyces cerevisiae were glycerol, acetaldehyde, acetic acid, lactic acid, and formic acid. The effects of these by-products on the cell growth and ethanol production were studied. By adding acetaldehyde or acetic acid in the fermentation broth, the cell growth decreased while the ethanol production increased. But glycerol and lactic acid had nearly no effects on the cell growth and the ethanol production. Acetic acid and acetaldehyde inhibited the cell growth by diminishing the growth rate as well as by prolonging the lag phase. The ethanol yield increased with the elevation of concentrations of acetic acid and acetaldehyde in the fermentation broth. The maximum ethanol yield was obtained for $3g/\ell$ acetic acid and $2g/\ell$ acetaldehyde, respectively.

• Food Science and Preservation
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• v.3 no.2
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• pp.171-178
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• 1996

This study was carried out for the purpose of improving the persimmon vinegar. The acetic acid bacteria strain JST-3, using acetic acid fermentation was isolated from the traditional persimmon vinegar. The optimum conditions for high yield of acetic acid were studied in the shaking bath. Acetic acid bacteria was cultured at 3$0^{\circ}C$ for 4 days and transferred to persimmon alcoholic juice for acetic acid fermentation. The optimum initial acidity for acetic acrid fermentation was 1%(w/v) and the addition of glucose or yeast extract was observed to produce relatively low yield of acetic acid. Succinic and acetic acid were major organic acid in the persimmon vinegar, The contents of lactic acid which was known to increase off-flavor were very low. Sensory evaluation revealed that the persimmon vinegar prepared in this study was superior to two commercial ones in the aroma and taste.

• Food Science of Animal Resources
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• v.24 no.3
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• pp.266-272
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• 2004

The objective of this study was to investigate the physicochemical characteristics of gelatin extracted from pork skin under soaking in various acid solutions (lactic acid, acetic acid, and citric acid). Gelatin sol was extracted at 8$0^{\circ}C$, frozen at -2$0^{\circ}C$ and lyophilized it for 3 days to be completely dried in freeze drying unit. In the evaluation of gelatin quality, gelatin soaked in citric acid showed higher L- and a-values than those of any other gelatin (p<0.05). Gelatin treated by acetic acid showed the highest gel strength, cohesiveness, and brittleness. The content of hydroxyproline amino acid in gelatin treated by acetic acid was larger than one of gelatin treated in lactic and citric acid in order. From the experimental results, the highest quality of gelatin in all of period, which was soaked in acetic acid and lactic acid, has a more good quality than gelatin soaked in citric acid.

• Journal of Microbiology and Biotechnology
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• v.29 no.9
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• pp.1341-1348
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• 2019

Acetic acid is indirectly involved in cell center metabolism, and acetic acid metabolism is the core of central metabolism, affecting and regulating the production of bacteriocin. Bacteriocin is a natural food preservative that has been used in the meat and dairy industries and winemaking. In this paper, the effects of acetic acid on bacteriocin produced by Gram-positive bacteria were reviewed. It was found that acetic acid in the undissociated state can diffuse freely through the hydrophobic layer of the membrane and dissociate, affecting the production, yield, and activity of bacteriocin. In particular, the effect of acetic acid on cell membranes is summarized. The link between acetic acid metabolism, quorum sensing, and bacteriocin production mechanisms is also highlighted.

• Journal of the Korean Chemical Society
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• v.59 no.3
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• pp.209-214
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• 2015

The formation of complexes between SO₂ and acetic acid was studied theoretically. The ab initio and DFT calculations were performed with MP2 and B3LYP methods using 6-311++G(d,p), aug-cc-pVDZ and aug-cc-pVTZ basis sets. Six stable complexes were identified, and three stable bidentate complexes, C1, C2 and C3, were formed between SO₂ and syn-acetic acid, which is more stable form of acetic acid. Anti-acetic acid also form three complexes, C4, C5 and C6, with SO₂. C4 is bidentate and C5, C6 are monodentate complexes, which are less stable. The most stable complex, C1 has S⋯O=C and O⋯H-O interactions, and the S⋯O and O⋯H distances are less than the sum of van der Waals radii. The vibrational frequencies of complexes were calculated and were compared with those of monomers. The frequency shifts after formation of complex were found, and the overall pattern of frequency shifts relative to monomers is similar among the six complexes.

• Korean Chemical Engineering Research
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• v.53 no.6
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• pp.695-702
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• 2015

Liquid-liquid extraction (LLE) using various solvents was studied for recovery of acetic acid from a synthetic ethanol fermentation broth. The microbial fermentation of sugars presented in hydrolyzate gives rise to acetic acid as a byproduct. In order to obtain pure ethanol for use as a biofuel, fermentation broth should be subjected to acetic acid removal step and the recovered acetic acid can be put to industrial use. Herein, batch LLE experiments were carried out at $25^{\circ}C$ using a synthetic fermentation broth comprising $20.0g\;l^{-1}$ acetic acid and $5.0g\;l^{-1}$ ethanol. Ethyl acetate (EtOAc), tri-n-octylphosphine oxide (TOPO), tri-n-octylamine (TOA), and tri-n-alkylphosphine oxide (TAPO) were utilized as solvents, and the extraction potential of each solvent was evaluated by varying the organic phase-to-aqueous phase ratios as 0.2, 0.5, 1.0, 2.0, and 4.0. The highest acetic acid extraction yield was achieved with TAPO; however, the lowest ethanol-to-acetic acid extraction ratio was obtained using TOPO. In a single-stage batch extraction, 97.0 % and 92.4 % of acetic acid could be extracted using TAPO and TOPO when the ratio of organic-to-aqueous phases is 4:1 respectively. A higher solvent-to-feed ratio resulted in an increase in the ethanol-to-acetic acid ratio, which decreased both acetic acid purity and acetic acid extraction yield.

• Korean journal of food and cookery science
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• v.30 no.6
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• pp.792-799
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• 2014

This study was conducted to determine the optimal conditions of acetic acid fermentation of aronia using the response surface methodology (RSM). Alcohol content of aronia wine was 13.1% after alcohol fermentation of aronia fruits. The optimal conditions of acetic acid fermentation were determined by five levels of initial aronia alcohol content, initial acetic acid content, and acetic acid bacteria, using the central composite design. The acetic acid yields, residual alcohol contents, pH, and color values (L, a, b) of acetic acid fermentation products were very significantly different ($p{\leq}0.01$), and were 26.34~57.82 g/L, 0.80~1.53%, 3.19~3.43, 47.58~71.00, 31.77~51.15, and 18.45~48.57, respectively. For the results, the optimal conditions of acetic acid fermentation of aronia were 7.78% of the initial alcohol concentration, 1.58% of the initial acetic acid, and 19.39% of the acetic acid bacteria.

• KSBB Journal
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• v.11 no.2
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• pp.125-131
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• 1996

In this study, Bucillus amyloliquefaciens was adopted as bacterial source to investigate the concentration of carbon source by adding inhibitors in the batch culture. By adding acetic acid at $10g/\ell$ of initial glucose concentration, maximum dry cell density was obtained with the highest value of /$\3.9gell$ at $1.0g/\ell$ of initial acetic acid concentration. By adding acetic acid al 10g/$\ell$ of initial glucose concentration, maximum ${\alpha}$-amylase production was obtained with 331.55unit/m1 at $2.0g/\ell$ of initial acetic acid concentration. ${\alpha}$-Amylase production was decreased with the increase of initial acetic acrid concentration. By adding acetic acid to the medium, cell growth and ${\alpha}$-amylase production was higher in glucose than in maltose. By adding lactic acid to the medium, cell growth was decreased.