• Korean Journal of Food Science and Technology
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• v.31 no.3
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• pp.778-787
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• 1999

This study was conducted to standardize the quality of sigumjang. The characteristic of producing method for sigumjang had smoking step. The major component of the amino acids of sigumjang was proline followed by valine, glutamic acid and alanine. Among the organic acids, only acetic acid and propionic acid were detected. The sugar component of sigumjang was composed of glucose predominantly, followed by maltose and fructose. The relation between taste components and sensory scores was analyzed by method of multiple regression analysis. Correlation between contents of taste components and sensory scores were significantly low. Among components of sigumjang inositol and fructose had the higest correlation with sensory scores. The result of multiple regression analysis, taste of sigumjang was explained about 90% with 16 taste components in case of relative value transformed with logarithm and 17 taste components in case of absolute value.

• Transactions of the Korean hydrogen and new energy society
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• v.13 no.4
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• pp.321-329
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• 2002

Clostridium butyricum, Lactobacillus amylophillus, Lactobacillus amylovorus, Lactobacillus acidophillus, AI-9 produced hydrogen and /or organic acids using glucose, lactose and starch at the anaerobic culture conditions. Cl. butyricum NCIB 9576 evolved 1,700 ml H2/L-culture broth and accumulated butyric acid, acetic acid, propionic acid and ethanol in its culture broth when lactose was used as a carbon source during 24 hrs of fermentation. L. amylovorus ATCC 33620 accumulated lactic and acetic acids and some reducing sugars when starch was used as a carbon source without hydrogen production. Instead of starch as a carbon source, L. amylovorus ATCC 33620 produced lactic acid from algal biomass during fermentation and the acid-heat or freeze-thaw pretreatment of algal biomass accelerate the lactic acid fermentation.

• Applied Biological Chemistry
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• v.9
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• pp.9-27
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• 1968

Studies were carried out in order to elucidate chemical components and microflora in three types of soy-sauce, 12-year aged soy-sauce prepared by improved method. 7-year aged and 20-year aged soy-sauce prepared by ordinary method. They results are summarized as follows: 1. The followings are found to be the important factors affecting the quality of soy sauce. a. Organic acids, reducing sugars and free amino acids were increased in the course of storage. b. In the aged soy-sauces under study non-volatile organic acid increased while volatile organic acid decreased and the total acidity was dependent only upon tie latter. c. It was found that suit concentration decreased during the storage. 2. The results of investigation of microflora in the stored soy-sauce are shown as follows. Soy-sauce Improved Ordinary Microbe 12-Y. 20-Y. 7-Y. Aerobic bacteria colony/1ml. 6 123 2 Halophilic lactic acid bacteria colony/1ml. 4 6 10 Osmophilic yeast colony/1ml. $828{\times}10^4$ 248 - b. In the stored soy-sauces, aerobic bacteria are incapable of growing due to drop in pH value and the influence of salt concentration. c. Halophilic lactic acid bacteria are incapable of growing due to drop in pH value, even the salt concentrations decreased during the storage. d. Osmophilic yeast are still growing in low pH value and in the decreasing salt concentration during the strage. 3. The results of amino acid analysis by paper partition chromatographic and calorimetric methods are shown as follows. a. Fourteen kinds of amino acid and thirteen amino acids were detected in the soy-sauce of 12-year aged improved soy-sauce and 7-year aged and 20-year aged ordinary one, respectively. b. The contents of aspartic acid, glutamic acid, serine, valine, leucine, lysine, histidine and methionine increased in the 20-year aged ordinary soy-sauce compared to the 7-year aged one. On the other hand those of alanine, tyrosine, phenylalanine and cystine decreased. 4. The results of sugar analysis by paper chromatography are as follows. a. In the 12-year aged improved soy-sauce, galactose, glucose, arabinose, xylose, rhamnose, maltose and an unknown were detected, and their amounts were in the above order except maltose and an unknown. b. Both in the 7 and 12-year aged ordinary soy-sauces, galactose, arabinose, xylose, glucose and rhamnose were detected and the amounts of the sugars were in the above order. c. In the non-aged ordinary soy-sauce, glucose was not detected but detected from 7-year and 20-year aged ordinary soy-sauce. 5. The results of organic acid analysis by paper chromatography were as follows. a. As volatile acids, acetic, propionic and butyric acids were detected in the 7-year aged ordinary soy-sauce. On the other hand in both the 20-year aged ordinary soy-sauce and the 12-year aged improved ones, only acetic acid was abundant while propionic and butyric acids were round in trace. It was found that propionic and butyric acids, as the unpleasant flavor components, decreased during the storage. b. In the ordinary soy-sauce, citric acid were produced during the storage and lack, malic and tartaric acids increased in the course of aging while succinic, glycolic, fumaric and malonic acids were shown to decrease. Glutaric and oxalic acids disappeared. Citric acid was produced also in the improved soy-sauce, but lactic, tartaric, succinic, malic, and glycolic acids decreased, while both malonic and glutaric acids disappeared. From the above results the citric acid production was considered to be a favorable factor for the taste. c. In the aged soy-sauces, pyruvic, α-ketoglutaric and probably acetoacetic and oxaloacetic acids (both in trace) were present and their amounts were in the above order. All of the α-keto acid abruptly decreased during the storage.

• Applied Biological Chemistry
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• v.50 no.1
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• pp.6-11
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• 2007

This study was carried out to evaluate the growth characteristics of Propionbacterium freudenreichii KCCM 31227 and production of organic acids in whey broth. Bacterial growth and increase rate of TTA (Total Titratible Acidity) were analysed. Log numbers of Propionibacterium freudenreichii KCCM 31227 was at the highest peak at 7.5${\times}10^7$ cfu/ml in fementation of 72 hr in 12% whey broth treated with low temperature long time method (60$^{\circ}C$, 30min) containing 1% yeast extract. TTA value of 12% whey broth treated with low temperature long time method and containing 1% yeast extract showed the highest peak at 5.2 in fermentation of 72 hr. The increase rate of cells and TTA in whey broth revealed almost the same tendency. Production of propionic and acetic acids showed higher value in the whey broth treated with low temperature long time method.

• Korean Journal of Environmental Agriculture
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• v.7 no.1
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• pp.34-42
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• 1988

To investigate the effects of paper sludge on seasonal variations of volatile lower fatty acids in paddy soil, paper sludge was applied to pots at the rate of either 300, 600, 900 or 1,200 kg/l0a which was either preadjusted at a C/N ratio of 30 : 1 or not adjusted. The decomposition rate of paper sludge, the evolution of $CO_2$, and the fractions of volatile lower fatty acids in the soil were determined. The results are summarized as follows: 1. Paper sludge was decomposed to $35{\sim}44%$, and its C/N ratio was $55{\sim}82$, respectively, at 120 days after treatment. 2. The evolution of $CO_2$, in the soil was proportional to the amount of paper sludge added. Significant positive correlations were observed the $CO_2$ evolution was compared with the decomposition rate of paper sludge, and volatile fatty acid contents in soil. 3. Acetic, propionic, butyric, i-butyric, valeric and i-valeric acids were identified in all the soils investigated. The content of the total volatile fatty acids in the soil increased with as the application of paper sludge increased. The formation of the acids was the highest at 25 days after treatment, and thereafter the contents of the acids decreased as time elapsed. 4. The volatile fatty acids in the soil inhibited the growth of paddy rice in early stages. The contents of acetic, propionic and i-valeric acids in the soil negatively, correlated with the uptake of N, $P_2O_5$, $K_2O$, CaO, MgO and $SiO_2$ in the paddy rice at 25 days after transplantation. In addition, the uptake of $P_2O_5$ and CaO in the paddy rice negatively correlated with the content of butyric acid in the soil. 5. The content of total volatile fatty acids positively correlated with the content of $Fe^{++}$ and $Mn^{++}$ in the soil at 25 days after transplantation. A significantly positive correlation was observed between $Fe^{++}$ and acetic acid contents in the soil.

• KSBB Journal
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• v.18 no.2
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• pp.149-154
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• 2003

The hydrogen-producing bacterium was isolated from fresh water and identified as Enterobacter cloacae. The isolated was named Enterobacter cloacae YJ-1. In batch culture, The optimum cultivation temperature and pH of strain YJ-1 was 35℃ and 7.5, respectively. All of the added glucose was consumed completely during fermentation even though pH was not controlled. Amount of hydrogen produced on each condition of 2% glucose, 4% sucrose and 5% fructose was 950, 1000 and 948 mL/L, respectively and resulted in increasing hydrogen production approximately 2.5-times more than controlled condition. The maximum hydrogen production was obtained when 50 mM phosphate was added. In repeated-batch culture, hydrogen gas of 1920 mL/L was totally produced for 48. The maximum hydrogen was produced on the condition of 0.5% yeast extract, but the production amount was not changed on the condition of over 0.5%. Most of the organic acids produced during the fermentation were formic and acetic acid, and propionic acid was moiety also generated.

• Journal of The Korean Society of Grassland and Forage Science
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• v.37 no.1
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• pp.1-9
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• 2017

This research was conducted to investigate the effects of feeding high and low forage diets with different forage sources on rumen fermentation characteristics and blood parameters of Holstein cows during the dry period. Eight Holstein cows were completely randomized assigned to two groups and repeated measurement was utilized in the analysis. Cows in two treatments were fed with diets with high (F:C = 70:30, 70F; forage source: mixed-sowing whole crop barley and Italian ryegrass silage, BIRG) and low (F:C = 55:45, 55F; forage source: tall fescue hay, TF) forage level. Rumen fluid pH was higher in 70F group. Levels of acetic acid, propionic acid, and butyric acid showed a similar pattern: from the lowest value at 07:30 h to the highest at 10:30 h and then decreased in both groups. The ratio of acetic acid to propionic acid was significantly higher (p < 0.05) in 55F group at 09:30 and 10:30 h. Rumen fluid $NH_3-N$ concentrations were significantly higher (p < 0.05) in 70F group at 09:30 and 10:30 h. Blood urea nitrogen was significantly higher (p < 0.05) in 70F group. It was concluded that BIRG based diet with a high forage level had no adverse effects on rumen fermentation, some blood chemical parameters, and immune system in dry Holstein cows and could be used as a forage source instead of imported TF.

• Korean Journal of Food Science and Technology
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• v.25 no.5
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• pp.430-437
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• 1993

This study was carried out for high quality mirin Production by fusant F-50. Cellularly fused between Aspergillus oryzae 9-12 and Aspergillus shirousamii 6082-60. The conventional and the improvement methods in Mirin-making by F-50 showed high level of total sugar, reducing sugar and amino-nitrogen of 42%, 38% and 0.18%, respectively. Free amino acids in Mirin were found to 387.2 mg% glutamic acid, 283.8 mg% arginine, 244.0 mg% leucine, 218.0 mg% aspartic acid, 231.1 mg% alanine, 168.3 mg% serine and 148 mg% phenylalanine. Organic acids in Mirin were contained: oxalic acid, citric acid, malic acid, succinic acid, lactic acid, acetic acid and propionic acid. Sugars such as glucose, maltose, isomaltose, maltotriose, ribose, isomaltotriose and isomatotertraose were also found in Mirin. The clouding formation of Mirin made by F-50 showed 0.03 alcohol clouding, 0.08 water clouding and negative heat clouding.

• Applied Chemistry for Engineering
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• v.4 no.2
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• pp.324-334
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• 1993

Chitin, the natural polymer has been known as harmless and innoxious material to human and has been also known to be biodegradable. Chitosan which was prepared by the deacetylation of chitin, was propionylated to obtain porous bead shaped propionyl chitosan and its possibility as a water-absorbant polymer was investigated. Propionyl chitosan porous bead was synthesized by acylation reaction using emulsion method of acetic acid solution and propionyl chitosan was partially crosslinked using ethyleneglycol diglycidyl ether. Through the experiment varying the moles of propionic anhydride, reaction time and reaction temperature, best results for water-absorption ability was obtained at reaction condition of 5 moles of propionic anhydride, 10 hours of reaction time and $22^{\circ}C$ of reaction temperature. The absorption ability to the distilled water, various salt solutions, artificial urine and artificial blood, absorption time and retention of water of synthesized porous bead were investigated and also mechanical strength after crosslinking was determined.

• Journal of Dairy Science and Biotechnology
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• v.31 no.2
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• pp.195-200
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• 2013

The ripening of cheese allows for the development of characteristic taste and flavour, nutritional substances, bio-active components and texture, helping to improve quality. Many different microbiological, biochemical and nutritional changes occur during the process depending on the quality of raw milk, added cultures and enzymes, as well as specific processing and ripening conditions. During the ripening lactose is hydrolyzed to lactic, propionic and acetic acid, helping to reduce potential effects of the problem of lactose intolerance. Fat is hydrolyzed to butyric, propionic and conjugated linoleic acid, which function as bio-active substances. Protein is hydrolyzed to different peptides and amino acids which all show various bio-activities. However, errors of cheese ripening can happen and affect the quality of the product. To guarantee good quality cheese the process needs to be managed carefully with the right microbes used and ensuring cleanliness of processing facilities, staff, ventilation and hazard analysis and critical control points (HACCP). Research into and controlling of ripening technology is crucial for producing high quality cheeses.