• Korean journal of food and cookery science
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• v.1 no.1
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• pp.8-17
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• 1985

Followings are the obtained results from the experiment of changes in content of proximate composition, free amino acid and nucleotides in soup prepared from beef brisket, leg bone, tripe and small intestine according to the diverse heating times-3, 6, 12, 18, 24, 30 hrs. The content of moisture in each sample is decreased from 97∼99％ in 8 hours heating to 95∼97% after heating 30 hours. On the contrary, the content of crude protein and crude fat are gradually increased in proportion to the length of heating times and it showed a rapid increasement when it was boiled 6∼12 hours long. We can extract the most protein from the soup stock of tripe among all samples ana the most crude fat from the leg bone. The contents of free amino acids is gradually increased in proportion to the length of heating times. Especially after being boiled longer than 18 hours it is increased obviously. In the soup stock prepared from the brisket, the lysine and alanine were contained the most. In leg bone soup stock, glutamic acid and histidine were extracted the most but bone soup stock, glutamic acid contents were decreased a little in longer heating. In the soup stock of tripe, glutamic acid which is contained very little in a raw material was extracted more as increasing times. In the soup stock of small intestine, lysine and glutamic acid were extracted the most. The least content in free amino acid from each sample was cystine which is sulphur-containing amino acid. These result suggest that, in order to get enough extraction of amino acid, crude fat, 18 hours heating is the most useful while 5’-IMP, which is the taste compound of meat, is extracted at 3 hours heating.

• Journal of the Korean Society of Food Culture
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• v.12 no.1
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• pp.53-61
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• 1997

This study was carried out in order to investigate general characteristics, sugars and organic acids contents of Korean traditional soy sauce, and to find out possibility of high quality soy sauce production in a short period through high concentration soy sauce making. In this study, we prepared three different types of soy sauce, low concentration soy sauce (Chungjang), high concentration soy sauce and Kyupjang, high quality traditional Korean soy sauce. pH of soy sauce were $4.46{\sim}4.90$ and did not show difference among three samples. Titratable acidity, buffering power and total free acid content were the highest value in Kyupjang. Kyupjang showed the highest contents of salt and pure extract. As the ripening period increased, the salt content increased in Chungjang samples, but decreased in Kyupjang. Reducing sugar contents of Kyupjang, high concentration soy sauce and low concentration soy sauce were 1.13%, 0.76% and 0.53%, respectively. Free sugar in soy sauce were analyzed maltose, glucose, galactose and fructose. Total free sugar content was highest in high concentration soy sauce, however, contents of glucose and fructose were higher in Kyupjang than in Chungjang samples. Galactose was the main free sugar in Chungjang, but glucose was in Kyupjang. Among identified volatile organic acid, acetic acid was present in the highest concentration, and volatile organic acid content was highest in the high concentration soy sauce at 150 days. 20 nonvolatile organic acids were detected in Korean traditional soy sauce. Succinic acid, lactic acid and 2,5-pyridine dicarboxylic acid were the main nonvolatile organic acid in soy sauce.

• Korean Journal of Pharmacognosy
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• v.38 no.2 s.149
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• pp.187-191
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• 2007

The extraction yield of the methanolic extracts and 19${\alpha}$-hydroxyursane-type triterpenoid (19${\alpha}$-HUT) fraction were investigated in the unripe and ripe fruits and the leaves of the four Rubus plants (Rubus coreanus, R. crataegifolius, R. phoenicolasius, R. pungens var. oldhami) to develop the biomaterial 19${\alpha}$-HUT mixture as functional foods. Thin layer chromatogaphy-Densitometer (TLC-DM) was used to analyze the individual quantity of 19${\alpha}$-HUTs using standard compounds (euscaphic acid, tormentic acid, 23-hydroxytormentic acid, kaji-ichigoside F$_1$, rosamultin, niga-ichigoside F$_1$). The content of methanolic extract of the fruits were higher in the ripe stage than in the unripe stage whereas the content of 19${\alpha}$-HUT mixture varied with each Rubus species. The Rubus plants containing the highest amount of 19${\alpha}$-HUTs in the leaves were R. coreanus, R. phoenicolasius and R. pungens var. oldhami while only R. cratagefolius showed the highest content in the ripe fruits. The mean of total genin content of 19${\alpha}$-HUTs was 0.94 mg/g; that of the glycosides was 0.60 mg/g. The genin quantity was found in the order of 23-hydroxytormentic acid> euscaphic acid> tormentic acid; the glycoside was observed in the order of niga-ichig-oside F$_1$> kaji-ichigoside F$_1$> rosmaultin, by which the biosynthetic pathway of 23-hydroxytormentic acid and its glucoside niga-ichigoside F$_1$ via the intermediates tormentic acid and/or rosamultin was presumed. It is also suggested that the ripe fruits of R. crataegifolius will be desirable to use as functional foods rather than unripe fruits.

• Journal of the Korean Society of Food Culture
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• v.7 no.4
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• pp.323-328
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• 1992

Three kinds of soy sauce were prepared using the brick type of conventional meju (A), the brick type of meju of Aspergillus oryzae (B), and the grain type of meju of Aspergillus oryzae (C) in summer. Free amino acids were analyzed in according to aging time of those products. Findings are as follows. Lysine, histidine, serine, glycine, valine, methionine, and phenylalanine were detected in all kinds of soy sauce at the beginning preparation. Aspertic acid, glutamic acid, alanine, threonine, arginine, and leucine were detected during 90 days. Isoleucine and tyrosine were detected during 180 days. Lysine and histidine were shown higher content among the detected free amino acids. The each content of glutamic acid, aspartic acid, and methionine was decreased in passing the aging time. The total content of free amino acids was shown 3,559-4,119 mg/100 ml at the 180 days. The total content of free amino acids of soy sauce C was higher than that of other soy sauces.

• Korean Journal of Microbiology
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• v.7 no.3
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• pp.115-124
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• 1969

The mash of Takjoo, Korean flour wine, is fermented through two brewing processes ; the primary brewing process to saccharify and the main one to produce ethyl alcohol. The activities of acid proteinase (pH3), weak acid proteinase (pH 6), and alkaline proteinase (Ph 80 on the processes are determined with time by the Folin phenol method as a strength of casein digestion. Hydrogen ion concentration, the content of total organic acids, protein, free amino acids and oligopeptides, which effect the activities of proteinase, are also measured. The results are briefly summarized as follows : 1. In general, the activities of acid proteinase and weak acid proteinase in the mesh of primary brewing process are stronger than those in main brewing process. 2. The activities of acid proteinase are remarkably stronger than those of weak acid proteinase in both processes. It reveals that they decrease slowly through the fermentation. Activities of alkaline proteinase are weaker than others. 3. As the raw materials are mixtured, the total amount of organic acids is equivalent to 0.150 mg/ml acetic acid in the mesh of primary brewing process and 0.02 mg/ml acetic acid in the main one. They increase gradually with time. 4. Hydrogen ion concnetration shows 3.9 in the mesh of main brewing process and 3.28 in the primary one. They increase to the maximum in 60-72 hrs., and decrease since 108 hrs. 5. The content of crude protein shows 66.90mg/ml in the mesh of main brewing process, while shows 64.29mg/ml in the mesh of primary one. they decrease slowly with time. it seems that a small content of crude protein, as a substrate, converts into amino acids and soluble nitrogen compounds by proteinase. 6. The content of free amino acids and oligopeptides shows 0.36 mg/ml in the mesh of primary brewing process and 0.24mg/ml in the main brewing process. It is evident that the reason they increase continuously through the fermentation is the effect of proteinase. 7. According to the results, the strong activities of proteinase in primary brewing process has been derived from the decrease of hydrogen ion concentration due to the production of organic acids.

• Journal of the Korean Society of Food Science and Nutrition
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• v.20 no.3
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• pp.214-219
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• 1991

The damaging effect of peroxidized lipid on amino acid was studied in rice bran by determining the free amino acid content in abiological system. The content of free amino acid in the rice bran stored in the controlled atomsphere of $35^{\circ}C$ with relative humidity of 65% for 180 days, increased during the first 60 days of storage, and then decreased as the lipid peroxidation proceeded. The content of free amino acid in the sample exposed to the air of $25-30^{\circ}C$ with relative humidity of 70-90% for 100 days decreased rapidly in the beginning period of the storage. The lipid oxidation developed much faster in the rice bran exposed to the air than in the rice bran stored in the controlled atmosphere. The correlation coefficients between the total content of free amino acid and degree of peroxidation for the samples of both conditions were above -0.8, which is significant(p<0.05). The changes in the concentration of serine, glutamic acid, proline, methionine, lysine, histidine, and arginine were significantly correlated with the degree of lipid oxidation(p<0.05) for the samples stored in the controlled atmosphere and the open air. It was observed that peroxidized lipid has damaging effects on protein in the bilogical system of rice bran.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.49 no.6
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• pp.779-784
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• 2016

We evaluated seasonal variations in the proximate, fatty acid and total amino acid compositions and mineral content of the muscles of wild and cultured Korean bullhead Pseudobagrus fulvidraco. The wild and cultured samples showed a significantly higher proportion of crude lipids than other components. Crude lipid content was highest in May in wild fish but lowest in May in cultured fish. We found no significant difference between wild and cultured samples in terms of fatty acid and total amino acid compositions and mineral content. The levels of saturated fatty acids (SFA) and polyunsaturated fatty acids (PUFA) as well as n-6/n-3, were higher in the muscles of wild fish compared with those of cultured fish. However, monounsaturated fatty acids (MUFA) levels were higher in cultured fish. Both wild and cultured fish were good sources of eicosapentaenoic acid (EPA) and docosa hexaenoic acid (DHA). In wild fish, the Mg and Zn contents were highest in August, while the Ca, P, Na, K, Fe, and Cu contents were highest in May. However, the mineral content of the cultured fish did not exhibit significant seasonal variation.

• Korean Journal of Food Science and Technology
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• v.31 no.6
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• pp.1453-1457
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• 1999

The optimal conditions of alkali isomerization to obtain conjugated linoleic acid (CLA) concentrate from vegetable oils which have antioxidant and anticarcinogenic properties were studied. The result of alkali isomerization of various vegetable oils indicated that CLA content of safflower oil which contains more linoleic acid than any other vegetable oils was the highest of all experimental vegetable oils. During alkali isomerization, the amount of cis-9, trans-11 CLA and total CLA content in safflower oil was the highest at $8{\sim}11%$ KOH concentration and $180{\sim}185^{\circ}C$. But heating time had no effect on CLA formation after $20{\sim}40$ minutes. As a result of alkali isomerization of neutral lipid, glycolipid and phospholipid in safflower oil, CLA content of neutral lipid class was higher than any other lipid classes. By urea treatment and HPLC fractionation, total CLA content in alkali-isomerized safflower oil increased to 95.4% from 78.9%.

• Korean Journal of Food Science and Technology
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• v.16 no.2
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• pp.169-174
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• 1984

The changes of the content of organic acids, carbon dioxide, alcohols and carbonyl compounds of the various Kimchis which were made of cabbage with green onion, garlic, ginger or red pepper and fermented at $12^{\circ}C-16^{\circ}C$ were investigated. Nonvolatile organic acids identified were lactic, succinic, fumaric and malic acid. Volatile organic acids identified were acetic, formic, propionic, butyric, valeric, n-caproic and n-heptanoic acid. Carbonyl compounds identified were acetaldehyde and acetone. The content of lactic acid was increased with fermentation, and higher in Kimchis containing red pepper, garlic and green onion. The content of acetic acid was increased with fermentation, especially in Kimchi containing garlic. The content of carbon dioxide was higher in Kimchi containing garlic. Alcohols identified in all Kimchis was only ethanol. Carbonyl compounds had no direct effect on off-flavor of Kimchi.

• Food Science and Preservation
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• v.6 no.4
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• pp.481-487
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• 1999

This study was determined to change in chemical composition of Mume(Prunus mume Sieb. et Zucc) fruits during maturation. There were no differences in the soluble solid and moisture content among varieties, but the soluble solid slowly increased with maturing. The pH and ash content were slightly decreased with maturation. The green color of 'Nanko' fruits was maintained for 92days after full bloom at the greeness value of -3.81 Whereas, the chlorophyll content of 'Koume' fruits remarkably decreased and it was not suitable for the processing of immature green Mume fruits. The titratable acidity increased during maturation. The organic acids were mainly composed of malic acid and citric acid. The malic acid was significantly decreased during maturation, whereas citric acid increased. Major free sugars and sugar alcohols were sucrose, glucose, fructose, sorbitol and maltose. Sucrose content increased as the maturity proceeded, whereas glucose and sorbitol were decreased. The total contesnt of free amino acids decreased with maturation and the total free amino acids in the flesh of fruits were occupied by asparagine at the range of 60 to 78%.