• Korean Chemical Engineering Research
• /
• v.44 no.1
• /
• pp.35-39
• /
• 2006

This study was performed to understand temperature effect on retention behavior of fructose and glucose as sugars and lactic acid and acetic acid as organic acids on poly (4-vinylpyridine) resin. The pulse tests were performed to understand temperature effect on retention time of sugars and the results were not shown large change. As it was able to predict with PVP resin not to be used for sugar separation generally, the results were shown poor resolution for separation of sugars and temperature effect on the resolution change of sugars also was not large. On the other hand, in the case of organic acids on PVP resin, the pulse tests were shown temperature effect on the retention behavior was very large. So, the frontal analyses were performed to understand quantitative adsorption behavior of organic acids at 35 and $65^{\circ}C$. These adsorption characteristics of organic acids with PVP resin system can be used to preparative chromatographic process such as SMB (simulated moving bed).

• Korean Journal of Food Science and Technology
• /
• v.27 no.1
• /
• pp.25-29
• /
• 1995

Organic acids and fatty acids of four different Kochujang prepared with different mashing methods were determined by HPLC and GC. Citrate, malate, lactate, succinate, formate, oxalate and acetate were identified. Citrate was found as a major organic acid ($450{\sim}565$ mg%) followed in decreasing order by lactate and malate. Total organic acid content of Meju Kochujang was the highest at the initial fermentation time, while that of koji Kochujang was higher than any other one after 90 days of fermentation. There was a little change of total acid among the treatments. Oleic acid was a major fatty acid ($68.59{\sim}75.38%$) during the fermentation of Kochujang. There was no significant change of fatty acids during the fermentation and among the treatments.

• Transactions of the Korean hydrogen and new energy society
• /
• v.15 no.4
• /
• pp.309-316
• /
• 2004

Chlamydomonas reinhardtii UTEX 90 was cultivated with continuous supply of 2% $CO_2$ using TAP media at $25^\circ{C}$ and produced biomass 1.18 g of dry cell weight/L for 4 days. C. reinhardtii algal biomass(CAB) was concentrated to 20 times by volume and converted into hydrogen and organic acids by anaerobic fermentation using Clostridium butyricum. Organic acids in the fermentate of CAB were consecutively used to produce hydrogen by Rhodobacter sphaeroides KD 131 under the light condition. Approximately 52% of starch in the concentrated CAB which had 4-5.8, 24-26 and 6-7 g/L of starch, protein and fat, respectively was degraded by Cl. butyricum at $37^\circ{C}$. During this process, hydrogen and some organic acids, such as formate, acetate, propionate, and butyrate, respectively were produced. Further conversion of the organic acids in anaerobic fermentate of CAB by Rb. sphaeroides KD131 produced hydrogen from the anaerobic fermentate under the illumination of 8 klux using halogen lamp at $30^\circ{C}$. The result showed that hydrogen was evolved by the anaerobic conversion using Cl. butyricum and then by the photosynthetic fermentation using Rb. sphaeroides KD131. It indicated that the two-step conversion process produced the maximum amount of hydrogen from algal biomass which contained carbohydrate, protein, and fat via organic acids.

• Journal of the Korean Society of Tobacco Science
• /
• v.6 no.1
• /
• pp.84-93
• /
• 1984

Six kinds of sugars (Maltose, Sucrose, Glucose, Fructose, Mannose and Lactose) and four kinds of organic acids (Malic, Tartaric, Lactic and Citric) were added by 2-10% for the former and 0.2-1.8% for the later in quantitatively to the inferior quality of Flue-cured leaf tobaccos, and treated at 135$^{\circ}C$ for 10 minutes to examine the effect on deliveries of tar and nicotine in smoke, variation of smoke pH and smoking taste. The results obtained are as follows. Tar and nicotine deliveries in smoke of tobacco show a great reduction with 5-6% addition of sugars. Reduction of nicotine delivery was to be 19% with addition of Glucose. Tar in smoke was, however, increased by 5-8% with 4% addition of Sucrose or Lactose. On the other hand, 4% addition of Glucose and Fructose gave 1 % reduction of tar delivery, but the reduction rate became to be small with increase of adding quantity. The smoking taste by the addition of Glucose and Fructose tobacco was found to be milder than by the other sugars. Tar and nicotine deliveries show a decreasing trend with the addition of organic acid, and Tartaric acid, among the organic acids described above, had greater effect than the other acids. 1% addition of Tartaric acid gaves 10-11% reduction in tar and nicotine delivery, and a fall of smoke pH, from 6.40 to 6.05, was found. Smoking taste by the addition of Lactic and Tartaric acid had milder than the others. And heat treatment for 10 minutes at $135^{\circ}C$ gave also better on smoking taste. The addition of mixture of sugars and organic acids, (Glucose 4%+Lactic acid 0.8% + Tartaric acid 0.2%) and then the successive heat treatment for 10 minutes at $135^{\circ}C$ improved greatly the quality of Fluecured leaf tobacco, and nicotine were reduced to 16-29%, and pH was changed from 6.46 to 6.14.

• Food Science and Preservation
• /
• v.9 no.2
• /
• pp.174-178
• /
• 2002

Changes in amino acids, organic acids and free sugars of soybean sprouts cultivated with extract of Glycyrrhiza glabra(GGE) during growth of 4 days were investigated. GGE was utilized as sprouting water of soybean and adjusted to 100 ppm, 200 ppm, 300 ppm and 400 ppm. Content of total amino acids of soybean sprouts cultivated with GGE was the most abundant, when soybean sprouts were cultivated for 3 days with 100 ppm of PGE. Content of aspartic acid was increased according to culturing days, but glutamic acid was shown to be a opposite trend. Content of total free sugar of soybean sprouts cultivated with GGE was lower than those of control group, and then increased by increasing of culturing days within GGE groups with same concentration. Sucrose of all groups during growth of soybean sprouts was decreased, but the other sugars were increased. Content of total organic acids was increased by increasing of culturing days and was the most abundant in soybean sprouts cultivated with 200 ppm of GGE among same groups. In conclusion, GGE as sprouting water of soybean was effective to increase of contents of amino acids and organic acids in soybean sprouts, indicating that GGE accelerated the quality of soybean sprouts.

• Journal of the East Asian Society of Dietary Life
• /
• v.25 no.2
• /
• pp.326-332
• /
• 2015

Makjang is a kind of Korean traditional short-term fermented soybean paste. The purpose of this study was to evaluate the compositions of free sugars, organic acids and free amino acids as well as microbial counts of six kinds of Makjang. Commercial Makjang from different regions (Kangwon-do, Choongchung-do and Kyungsang-do) were used. The major free sugars of samples were glucose (0.15~3.97%) and maltose (0.01~0.54%), whereas sucrose (0.02%) was detected only in M4 and fructose only in M1 and M2. The major organic acids were citric acid (0.16~3.09%), malic acid (0.06~0.23%) and succinic acid (0.01~0.11%). The total content of free amino acids ranged from 0.02 to 8.74 mg/g, and major amino acids were detected in the order of glutamic acid, leucine, alanine and aspartic acid. Numbers of viable cells of bacteria as well as yeast and molds were $7.8{\times}10^4{\sim}4.8{\times}10^5$ and $8.1{\times}10^3{\sim}3.6{\times}10^4$, respectively. The results of the sensory evaluation showed that over-all preference of Kyungsang-do Makjang was higher than others. Consequently these results provide better information for standardizing and improving quality and functional activity of commercial Makjang.

• KSBB Journal
• /
• v.19 no.6 s.89
• /
• pp.478-483
• /
• 2004

The optimum fermentation conditions of Propionibacterium acidipropionici were determined for the maximum production of organic acids. Three strains of P. acidipropionici, ATCC 25562, 4875, 4965 were selected to test the productivity of organic acids in the batch fermentation. Nutrients and environmental conditions on cell growth were defined by series of experiments, and the optimum amounts of peptone, yeast extract were determined to be $1.5\%$ (w/v), $0.75\%$ (w/v), respectively. The yields and productivity were highest at pH 6 among the ranges of $5.0{\sim}7.5$, and ATCC 4965 was determined to be the best strain compared to the others by getting total productivity of 0.29 g total acids/L/h. Approximately $1.60{\sim}2.34$ moles of propionic acid and $0.74{\sim}1.05$ moles of acetic acid were produced from 1.5 moles of glucose.

• Journal of dental hygiene science
• /
• v.19 no.1
• /
• pp.1-8
• /
• 2019

Background: Erosion is a gradual process that occurs fairly quickly, and the full extent of the erosive effects of acidic beverages is not yet clear. The present study aimed to determine the differences in the erosive potentials among four naturally acidic fruit nectars within the same range of titratable acidity and to determine the influence of the components of organic acids on tooth erosion. Methods: Diluted fruit nectars (mandarin 1:1.1, orange 1:1.7, lemon 1:15, grapefruit 1:20) with the same range of titratable acidity (7.9 ml) and their corresponding organic acids (0.05%, 0.1%, 0.3%, and 0.5% citric acid, malic acid, and a citric and malic acid mixture [pH 2.8], respectively) were used. Specimens were placed in conical tubes with 50 ml of each of the test solutions for 1 hour. A microhardness test and scanning electron microscopy were used to measure enamel erosion. Acid separation was carried out using high-performance liquid chromatography to analyze the composition of each test solution. Results: Similar decreases in the Vickers hardness number (VHN) were observed among the groups treated with the following diluted fruit nectars: diluted mandarin nectar ($75.9{\Delta}VHN$), diluted lemon nectar ($89.1{\Delta}VHN$), diluted grapefruit nectar ($91.7{\Delta}VHN$), and diluted orange nectar ($92.5{\Delta}VHN$). No statistically significant differences were found in the enamel surface hardness after erosion (p>0.05). Citric and malic acids were the major organic acids in the test fruits. The lemon and orange groups had the highest malic acid concentrations, and the mandarin group had the lowest malic acid concentration. Conclusion: The titratable acidity and the citric and malic acid contents of the fruits could be crucial factors responsible for enamel erosion. Therefore, fruit-based drinks should be regarded as potentially erosive.

• Journal of the Korean Society of Food Culture
• /
• v.23 no.1
• /
• pp.121-129
• /
• 2008

To produce buckwheat sprouts, buckwheats were germinated at $23{\pm}2^{\circ}C$ up to 8 days in total darkness. In proximate analysis, moisture content increased from 13.87% of buckwheat groats to 93.75% of buckwheat sprouts on the 8th day of germination. On dry weight basis, lipid and ash contents increased like as protein content increased from 13.45% to 21.82% while carbohydrate content decreased due to enzyme hydrolysis. Amino acids were rich in glutamic acid, aspartic acids, and lysine, and also the ratio of the essential amino acids to total amino acids increased from 26.84% to 36.84%. Vitamin C did not exist in buckwheat groats but its content has continued to increase as far as 99.56 mg/100 g buckwheat sprouts. Rutin continued to increase by HPLC analysis from 4.71 mg/100 g buckwheat groats to 1,524 mg/100 g buckwheat sprouts. In analysis of organic acids, oxalic, maleic, and citric acids were commonly found in buckwheat sprouts. Fagopyrin was found almost none in buckwheat sprouts. In conclusion, the conversion of buckwheat seeds into sprouts through germination in darkness results in physically different final product with nutritional changes such as higher content of rutin, generation of vitamin C, abundance of the essential amino acids, and the existence of fagopyrin on very little.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.11 no.2
• /
• pp.65-83
• /
• 1978

This study was attempted to evaluate the taste of broiled-dried sea mussel which is a traditional dried Sea food in Korea. The contents of such compounds as free amino acids, nucleotides and their related compounds, TMAO, betaine, and nonvolatile organic acids were analysed. From the results of analysis of nucleotides, the contents of AMP and ADP in broiled-dried Mytilus coruscus and Mytilus edulis appeared higher than other nucleotides and tended to increase slightly after cooking, drying, and storage which might be due to both their stability and the addition of degradation of nucleic acids during cooking. In the free amino acid composition of fresh samples abundant amino were taurine, glycine, serine, glutamic acid, alanine, arginine, threonine, tyrosine, lysine and valine in order. Such amino acids as histidine, leucine, methionine and isoleucine were poor and both proline and phenylalanine were merely trace. The free amino acid composition in the extract of Mytilus corucus and Mytilus edulis after broil-drying was not changed. These amino acids, taurine, glycine, feline, glutamic acid, alanine and arginine were abundant in dried samples as well as in the fresh. The total free amino acid was greatly reduced after cooking and drying ranging from $76.3\%$ to $79.7\%$ loss to that of tile fresh. The content of betaine shelved the same tendency as in total free amino acid while TMA slightly increased relating to TMAO decrease during broil-frying. Such nonvolatile organic acids as succinic, lactic, malic and fumaric acid were abundant in both fresh and broiled-dried samples whereas oxalic and pyruvic acid were poor. It is found that the taste compounds of broiled-dried Mytilus coruscus and Mytilus edulis were composed of amino acids as glycine, serine, alanine, glutamic acid, arginine, and betaine, TMAO, ADP, AMP, and organic acids such as succinic acid, lactic acid, malic acid and fumaric acid. No significant differences in the taste compounds between male and female as well as between Mytilus coruscus and Mytilus edulis was not observed.