• Journal of the Korean Society of Food Science and Nutrition
• /
• v.30 no.3
• /
• pp.382-387
• /
• 2001

Characteristics of six commercial samjangs were analyzed such as proximate composition, free amino acids, organic acids and free sugars. Also color, taste and odor were evaluated by 36 panelists. They were composed of moisture content 41.4-48.4%, crude protein 9.2-10.4%, crude fat 2.2-3.4%, pH 5.3-5.7, amino nitrogen 194.0%-375.6 mg% and sodium chloride 7.7-9.1%. Total free amino acids of samjangs were 975.89-2304.98 mg%. Glutamic acid was the highest amino acid among free amino acids as 231.7-788.01 mg%. Proline, arginine, alanine and lysine were higher than other free amino acids while histidine, cystine and methionine were lower than other. Eleven free amino acids including glutamic acid were the highest in samjang (B) which contained more doenjang than any other makers did. Total organic acids were 401.01-640.27 mg%. 69.65-269.07 mg% of succinic acid was the highest among organic acids. Lactic acid was the highest in samjang (F) which was home made. Total free sugars was the highest in samjang (A) which contained more wheat flour than any other makers did it. Glucose was 9.30-23.99% and fructose was nd-2.69%. The result of proximate composition showed a different pattern comparing with that sensory evaluation. Samjang (A) which contained less salt showed the highest overall acceptability while samjang (F) which contained more dark color, more salt was the lowest one among the samples.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.17 no.2
• /
• pp.136-143
• /
• 1988

This study was performed to provide the optimal conditions of quantitative analysis for free amino acid in fermented protein foods. The water extractable free amino acid from dairy fermented foods was extracted effectively at $75^{\circ}C$ for 40 min., while it were extracted from fermented soy products at $40^{\circ}C$ for 3 hours. A close results of free amino acid content to those from amino acid analyzer were obtained using OPDA method with lysine standard after deproteinizing with 1% picric acid. 95% ethanol used as a deproteinizing reagent could give a comparable results to those from picric acid treatment in determining free amino acid content using OPDA method. Therefore, ethanol treatment was more recommendable than picric acid treatment which has some troubles in removing excess picric acid through Dowex resin column. The most desirable precipitation method for free amino acid determination using TNBS method was 95% ethanol treatment among the various deproteinizing procedure. The copper salt method was not suitable owing to its lacking reproducibility and pronounced discrepancy in determining free amino acid.

• Preventive Nutrition and Food Science
• /
• v.16 no.1
• /
• pp.55-61
• /
• 2011

A survey aiming to find out the chemical and textural properties of commercial fermented soy bean curd called sufu was conducted. Sixteen brands of plain sufu produced in the Northern or the Southern part of China were collected and examined for their crude protein, crude fat, texture profiles, free amino acids, and free fatty acid contents. Twenty-one free amino acids were extracted and derivatized using a commercial kit followed by separation and analyzed by the gas chromatography-mass spectrometry (GC-MS). Similarly, ten free fatty acids were extracted using alumina, eluted, separated and analyzed. The content ranges of crude fat and protein were 22~36% and 31~38%, respectively. In texture profile analysis, ranges of the texture parameters were 131~493 g (hardness), 0.4~0.5 (cohesiveness), -137 to -50 gs (adhesiveness), 0.6~1 (springiness), 47~220 g (gumminess) and 32~177 g (chewiness). Twenty-one different free amino acids, especially alanine, glycine, $\alpha$-aminobutyric acid, valine, leucine, allo-isoleucine, aspartic acid, glutamic acid and lysine in large amount, as well as ten fatty acids in total, notably linoleic acid (9-octadecanoic acid), oleic acid (9,12-octadecadienoic acid), linolenic acid (9,12,15-octadecadienoic acid), hexadecanoic acid and octadecanoic acid were found. This information provides important quality reference ranges for product developers and manufacturers to optimize and produce the plain sufu.

• Korean Journal of Microbiology
• /
• v.5 no.2
• /
• pp.79-85
• /
• 1967

Kim, Jong Hyup., (Div. of Biology, Atomic Energy Research Institute,Korea.;) Studies on the Cellulor Metabolism in Microorganisms as influenced by Gamma-irradiation(III): On the Changes of Free Amino acid Pool and content of Protein in Yeast clls irradiated by .gamma.-ray. 1. The strain of Saccharomyces cerevisiae had been cultured synchronously in aerobic condition and irradiatel by gamma-ray from the source of cobalt-60. Drying in vacuum oven at $90^{\circ}C$ C over 12 hours, then changes of protein content (Kjeldahl) and free amino acid pool have been assayed with use of spectrophotometer. Results obtained were compared with those of unirradiated normal cells. 2. It is proved that amount of protein content in the irradiated cells increases to seven percent more than those of normal cells in the same weight of dried samples. It seems like carbohydrate breakown had been stimulated by irradiation and that relative contents of protein shows higher values than those of normal in the same weight of samples. 3. The amount of free amino acid pool in the irradiated cells shows less value about ten percent than those of normal cells, and rate of decreasing is also weak than those of standard reagent solution of amino acid. We may assume that free amino acid pool would be protected against radiation damage in living cells and more stable than in vitro. 4. The component of free amino acid pool have been assayed on second dimensional paper chromatogram, and the identified amino acids are as follows; aspartic acid, serine, glutamic acid, cystine, lysine, glycine, threonine, histidine, arginine, tyrosine, phenylalanine, valine and leucine. 5. Distributional presence of free amino acids are identical to that of normal cells except arginine, it is cosumable that radiation effect is univerlsal to all amino acid. However it is obvious that there are differences in radiolabilities of amino acids in irradiated cells.

• Journal of the Korean Wood Science and Technology
• /
• v.22 no.1
• /
• pp.34-39
• /
• 1994

Effects of Mg-base acid sulfite and Mg- or Na-base bisulfite on pine bark cooking were examined. In the presence of 75 % free acid at 145 $^{\circ}C$, the rate of cooking and delignification was improved with the increase of total acid. However, the delignification could not be achieved by 50 % or more under these cooking conditions. When cooked with 50~65 % free acid and at 155~165 $^{\circ}C$, the rate of cooking and delignification was remarkably improved. Thus, the bark was delignified up to 73 % when cooked for 2 hours in the presence of 50 % free acid and 24 % total acid. Na-base bisulfite was slightly more effective than Mg-base bisulfite for cooking, giving 76 % delignification of pine bark. However, there was no significant difference in selectivity of delignification between Na- and Mg-base bisulfite cooking.

• Korean journal of food and cookery science
• /
• v.17 no.1
• /
• pp.80-90
• /
• 2001

This study was carried out to investigate to proximate compositions, free sugars, organic acids, amino acids, and volatiles from the fresh leaf, root and seed of coriander. The research results are as follows: Moisture was 79.93% in the leaf, 81.89% in the root. Crude protein, crude lipid and crude ash were the highest in the seed. Ascorbic acid was 65.4mg% in the leaf and 37.83mg% in the root. Glucose, fructose and sucrose were the major free sugars. Glucose was 7.92mg% and fructose 7.51mg% in the leaf. Sucrose was 17.34mg% in the root, highest level. Among organic acids, malic acid was 354.55mg% in the leaf, the highest level. The content rate of organic acids was high in the order of leaf, seed and root. The content rate of total amino acid was high in the order of seed, root and leaf. Glutamic acid and aspartic acid were high in the leaf and root. Glutamic acid and proline were high in the seed. The content rate of free amino acid is the same as that of total amino acid. Glutamic acid and serine were high in the leaf and seed. Glutamic acid and treonine were high in the root. The contents of total amino acid in each parts of the coriander was higher than that of free amino acid, The composition of amino acid in the total amino acid and free amino acid was different. The volatile constituents were extracted by steam distillation method and analyzed by GC-Mass. The content of the volatile constituents was 45.31mg% in the leaf, (E)-2-decenal was the highest, followed by decanal, 2-dodecenal, (E)-2-decen-1-ol in order, aldehyde and alcohol was major constituents. The content of the volatile constituents was 36.01mg% in the root and 54.37mg% in the seed. linalool was the highest in the root and seed. it was 22.27 %, 53.67% in root and seed.

• Journal of Nutrition and Health
• /
• v.31 no.2
• /
• pp.126-134
• /
• 1998

Our previous study demonstrated that dietary taurine or glycine supplementation significantly lowered plasma and hepatic cholesterol and triglyceride concentrations in rats fed a cholesterol-free diet. In the present study, the effect of long term dietary taurine or glycine supplementation, for the purpose of preventing and/or treating of hyperlipidemia and other known biological functions, on plasma and hepatic free amino acid concentrations and profiles were evaluated in rats. Three groups of male rats(110-130g) were fed a control diet(CD), taurine-supplemented diets(TSD ; CD+ 1.5% taurine) or glycine-supplemented diet(GSD ; CD+1.5% glycine) for 5 weeks. Plasma and hepatic free amino acid concentrations were determined by an automated amino acid analyzer based on ion-exchange chormatography. The feeding of TSD for 5 weeks yielded a 444% higher plasma taurine concentration , and the feeding GSD for the same period resulted in a 143% higher plasma glycine level in rats compared to those fed DB. Hepatic taurine concentration was significantly higher in rats fed TSD(145% increase) compared to the control rats. However, hepatic glycine concentration was not influenced by dietary glycine supplementation , which implies that the massive dose of glycine entering the body was more rapidly metabolized or excreted than taurein. Dietary taurine or glycine supplementation resulted in similar changes in plasma free amino acid concentrations, except in levels of taurine and glycine. Plasma levels of histidine, lysine, phenylalanine , alanine, proline, hydroxypoline, $\alpha$-aminogutyric acid, cystathionine and ethanolamine were significantly higher in rats fed TSD or GSD than those fed GD. Glycine supplementation did not change hepatic free amino acid concentrations as compared to CD. Concentrations of most hepatic free amino acids were not influenced by dietary taurine supplementation with the exception of significantly higher levels of asparate and tyrosine(56-63% increase) and lower levels of histidine and glutamate(33-34% decrease) compared to the control rats. These results suggest long-term dietary taurine or glycine supplementation resulted in increases in most plasma free amino acid levels, but did not cause a characteristic change in plasma aminogram pattern compared to rats fed CD.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.41 no.2
• /
• pp.139-144
• /
• 1996

Effects of anaerobic, mechenical wounding and cold treatments on free amino acid and free sugar contents were examined in 7 day-old barley seedlings. In barley shoots under anaerobic condition, drastic changes in free amino acid content were observed. Alanine, ${\gamma}$-aminobutyric aicd(GABA) and glutamic acid contents changed most prominantly. Alanine and GABA contents increased rapidly with incubation time up to 10 hr. Glutamic acid content, however, decreased drastically during the first 5 hr of incubation, then increased thereafter. Barley shoots showed similar but smaller changes in amino aicd contents in response to mechanical wounding. GABA content increased in shoots and roots in response to the cold treatment. But increase in GABA content was greater in anaerobic than cold treatment. In anaerobically treated shoots, changes in free sugar content were less prominant than those in amino acid content. Sucrose content changed relatively larger than glucose and fructose contents in excised shoots.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.14 no.3
• /
• pp.301-304
• /
• 1985

Changes of free amino acids and free sugars in steamed and roasted green tea were determined after heat treatment at $110^{\circ}C$. Sixteen kinds of free amino acids and four kinds of free sugar were analyzed by HPLC. Free amino acids isolated were aspartic acid, threonine, serine, glutamic acid, proline, glycine, alanine, valine, methionine, isoleucine, leucine, tyrosine, phenylalanine, histidine, lysine and arginine. Free sugars were sucrose, glucose, fructose, and raffinose. After the heat treatment, free amino acids and free sugars were decreased considerably.

• Journal of Nutrition and Health
• /
• v.20 no.6
• /
• pp.456-462
• /
• 1987

Chemical composition, free amino acid and fatty acid composition of wild and cultured cockle clam were studied. 1. The content of crude protein was higher in Anadara suberenata thanthat ini Anadara granosa. The contents of crude protein and ash increased after boiling. 2 Free amino acid composition of Anadara granosa was similar to that of Anadara suberenata. Both glutamic acid and aspartic acid among free amino acid were the most abundant in cockle clam. Next, leucine, arginine and lysine were abundant in order. They all composed of approximately 50%^ of total amino acid content. Whereas the contents of cystine and methionine were poor. 3. In cockle clam the major fatty acids consisted of C16 :0, C18: 0, C18 ;1 and C18:3 in order. The level of C16 :0 was the highest in lipids. The levels of C18 : 0 and C14 :0 were higher in Anadara granosa than those in Anadara suberenata, while the levels of C16 :0, C18 :3 and C16 : 1 were higher in Amadara suberenata than those in Anadara granosa.