• Proceedings of the Korea Hospitality Industry Research Society Conference
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• 2003.05a
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• pp.51-58
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• 2003

The autoclave method and the traditional cooking method are compared for nutrients, mineral, color difference, viscosity, reducing sugar and amino nitrogen content of brown stock. For protein and amino nitrogen contents, the autoclave cooking method is better than the traditional cooking method. Also, reducing sugar content is increased by the autoclave cooking method. Since the color of brown sauce is related with reducing sugar content, the autoclave cooking method is more effective than the traditional cooking method for the color of brown sauce. Since the autoclave method can reduce the cooking time without the loss of quality in brown stock, the traditional method can be substituted by this new method.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.4
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• pp.595-600
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• 1997

To extend the shelf-life of Kochujang, the effects of anti-browning agents and their optimum concentrations were evaluated using organic acids as synergists. Among the physicochemical analyses, amino nitrogen content exhibited the highest correlation with sensory score. Ascorbic acid and citric acid were selected among the anti-browning agents(ascorbic acid, potassium sorbate, calcium chloride) and organic acids(citric acid, lactic acid, oxalic acid) tested on the basis of the highest amino nitrogen content during storage at 55$^{\circ}C$. The appropriate concentration of ascorbic acid was 0.03% based on amino nitrogen content during storage at 55$^{\circ}C$. Combination of 0.06% citric acid with 0.03% ascorbic acid showed the highest amino nitrogen content during storage at 55$^{\circ}C$. From the results, the 0.03% ascorbic acid and 0.06% citric acid were selected as additives for extending the shelf-life. Control(no additive) and additives(0.03% ascorbic acid and 0.06% citric acid) were tested for physicochemical and sensory analyses during storage at 45$^{\circ}C$ and 55$^{\circ}C$. Amino nitrogen content was also highly correlated with sensory score, The marginal amounts of amino nitrogen for control and additives were 174.9mg% and 173.2mg%, respectively. Degradation rate of amino nitrogen was a first order reaction. Compared to control, the predicted shelf-life for adding additives increased 69% and 56% at 45$^{\circ}C$ and 55$^{\circ}C$, respectively.

• Korean Journal of Soil Science and Fertilizer
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• v.10 no.1
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• pp.29-37
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• 1977

The mineralization of soil nitrogen, amino acid composition of acid hydrolizable organic nitrogen of four Korean soils were investigated in comparison with four Japanese (Hokuriku district) soils which is similar in nitrogen content but different in characteristics of clay minerals. The mineralization rate and pattern were quite different between Korean and Japanese soils; Korean soils were low in amount of mineralized nitrogen but porduced much ammonium nitrogen during the later stage of incubation. In Korean soils the ratio of acid hydrolizable nitrogen to total; especially ${\alpha}$-amino nitrogen and hydrolizable ammonium nitrogen were low while hexosamine content was considerablly high (greater than 10%) In all soils the amount of mineralized nitrogen showed significant positive correlation with ammonium nitrogen and ${\alpha}$-amino nitrogen in acid hydrolizate. The amino acid composition of acid hydrolizate of paddy soils showed higher in basic amino acids and lower in acidic amino acids than those of up land soils (humic volcanic ash soil) from both countries. Alanine content was low in Korean soils. Proline showed increasing trend with nitrogen content but aspartic acid decreasing.

• Asian-Australasian Journal of Animal Sciences
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• v.11 no.5
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• pp.620-633
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• 1998

Methods developed for measuring digestibility and availability of amino acids in feedstuffs used in pig nutrition are reviewed. Digestibility is a proportion of an amino acid in a feed that is absorbed from the digestive tract and should be determined from the difference between the amount of amino acid consumed and passing the distal ileum. Techniques for ileal digesta sampling including various types of cannulas: a re-entrant, T-piece, IPV, IPVC and ileaorectal anastomosis are described and comparisons amongst these methods are presented. Other methodologies like mobile bag technique, in vitro assays and mathematical prediction method are also described. Significance and methodologies for measurement of endogenous nitrogen and amino acids losses at the distal ileum and their effect on the apparent and true nitrogen and amino acid digestibilities in feeds are discussed. Factors influencing the apparent and true amino acid digestibilities such as dry matter intake, protein, fibre and antinutritive compounds content in the diet are discussed. Amino acid bioavailability -the proportion of the total amino acid digested and absorbed in a form utilized in metabolism - measured by the growth assay may differ from its ileal digestibility. Chemical methods for determination of available lysine content in heat treated feeds are evaluated.

• The Korean Journal of Food And Nutrition
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• v.8 no.3
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• pp.184-191
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• 1995

This study was designed to investigate the changes In chemical characteristics of traditional kochujang increase in fermentation time, whereas that of total sugar decreased rather rapidly during aging of meju. Amino nitrogen content of meju Increased sharply up to 40 days of fermentation and then decreased there after On the other hand, ammoniacle nitrogen content continued to increase with increasing aging time. Initially, maltose was the most abundant free sugar, but was later replaced by glucose or fructose as the fermentation proceeded. Among non-volatile organic acids, pyroglutamic acid was present at an appreciably other organic acids did not change considerably during fermentation. The total free amino acid content Increased up to 40th day of aging and then decreased thereafter The was the most abundant amino acid followed in decreasing order by Try and Glu in meju fermented for 40 days.

• Biotechnology and Bioprocess Engineering:BBE
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• v.8 no.6
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• pp.368-372
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• 2003

The growth and amino acid contents of the cyanobacterium, Spirulina platensis strain NIES 46, were investigated using ammonium, nitrate, nitrite, or urea as the sole nitrogen source in a batch culture. Chlorophyll a concentration was highest at 2,096$\mu\textrm{g}$/L in the nitrate group after 10days of cultivation, while the dry weight of S. platensis was highest at 4.5g/L in the ammonium group after 30days of cultivation. The total amino acid content was highest at 174mg/g dry weight of S. platensis in the urea group at the end of the cultivation period, yet the amino acid patterns for S. platensis were similar for all the experimental groups. Therefore, it seemed that the growth and amino acid composition of S. platensis varied depending on the type of nitrogen sources, while the amino acid patterns were not changed. Also, the most efficient harvesting time for S. platensis seemed to be approximately 10 days after cultivation.

• Applied Biological Chemistry
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• v.15 no.1
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• pp.35-40
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• 1972

The contents of free amino acids in deembryod brown rice of two varieties were investigated by amino acid autoanalizer in relation to specific gravity grade. The analytical methods of free amino acid were also discussed. 1) The lower the specific gravity of the unhulled rice the higher the content of total free amino acids in the deembryod brown rice, and the similar trend appears to hold on each amino acids. 2) Main free amino acids were serine+asparagine, glutamic acid, aspartic acid, alanine and valine, and maximum values of them were 7.3, 5.1, 4.0, 3.4, 0.9mg/100g rice, respectively. They consist about 85% of total free amino acids in most cases. 3) The contents of soluble nitrogen and free amino acids appear to be lower in high protein variety (IR 667) than in low protein variety (Jinhung). The percentage of free amino acid nitrogen to soluble nitrogen, however, appears to be higher in high protein variety (IR 667). 4) Alanine was much lower than aspartic acid in IR 667 having Indica blood while alanine appears to be higher than aspartic acid in Jinhung (Japonica rice) suggesting varietal difference in amino acid metabolism. 5) Threonine peak was overlaped with glutamine, and serine was with asparagine in this study.

• Journal of Ginseng Research
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• v.14 no.2
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• pp.317-331
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• 1990

Nitrogen compounds of Panax ginseng and their biological activities in plant and animal were reviewed. Major nitrogen combounds found in P. ginseng are free amino acids, Water soluble teins, insoluble proteins and peptides. Minor nitrogen compounds are dencichine. glycol)roteins. amines, alkaloides, methoxy or alkyl pyrazine derivatives. free nucleosides and nllrleir arid bases. 4-me- thymi-5-thiazoleethanol and pyroglutamic acid. The contents of total nitrogen and protein in root increased until 13 years old rvhich was the highest age tinder investigation. Soluble protein content increased With the root weight and was higher in xylem pith than cortex-epidermis indicating the rlosc relation with root growth. Arginine which covered 58% of total free amino aroids may serve as a storage nitrogen. Arginine seems to be changed into proline in rhizome, threonine in stem and again threoning and arginine in leaf. The greater the root weight the higher the polyaminc content. Polyamine stimulated the growth of root callus. Physiological roles of other minor nitrogen compounds are unknown although dencichine content is relatively high (0.5% d.w.). biochemical and pharmatological activities of some nitrogen compounds for animal were more investigated than physiological roll iota plant itself. Radiation and U.V. protective function (heat stable protein), insulin-like activity in lipogenesis and lipolysis (adenosine and pyroglutamic acid), depression of blood sugar content (glycopeptide). hemostatir and nellrotoxic activity (denrichine) and. sedative and hypnotic activity (4-methyl-5-thiazoleethilnol) are reported. Heat stable protein increased with root age. The traditional quality critsria appear to be well in accordance with biological activities of nitrogen compounds. Chemical stlldies of nitrogen compounds seem relatively rare, probably dole to difficulty of isolation, subsequently the investigations of biological activities are little.

• Korean Journal of Pharmacognosy
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• v.27 no.1
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• pp.6-14
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• 1996

To differentiate the quality of Korean ginseng from those of other habitats, the quantitative analysis of free amino acids(FAA) and total amino acids(TAA) in addition to ginsenoside Rb1 and Rg1 was carried out using amino acid analyzer and HPLC, respectively. FAA pattern in Korean ginseng was much different from that of Panax notoginseng. The difference in total content of FAA was also found that Korean ginseng contained 26.3-39.8mg/g while Panax notoginseng contained 6.5mg/g. This FAA content had a tendency to increase with the age of radix. The contents of FAA and TAA in Korean ginseng(6 years old) from Kumsan were shown to be the highest than other ginseng origins tested. The content in the 6 years Panax ginseng from China was about same with that of 4 years Korean ginseng of Kumsan. However, regarding to gisenoside Rbl and Rg1, which have been accepted as the characteristic components of Panax ginseng-Panax notoginseng showed considerably higher content than those of any other ginseng origin.

• Korean Journal of Food Science and Technology
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• v.26 no.4
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• pp.389-392
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• 1994

Changes in free amino acids and amino nitrogen of traditional kochujang were investigated during 180 days of fermentation. Tested kochujang included Sunchang kochujang prepared with glutinous rice, Boeun kochujang prepared with barley, and Sachun kochujang prepared with wheat. Amino acids remarkably increased during fermentation were methionine, glutamic acid, isoleucine, leucine and tyrosine. However, regardless of kinds of kochujang major free amino acids were serine, aspartic acid, glutamic acid and proline. Glutamic acid was noted as the most contributing to the savory taste of kochujang in relation to the increasing ratio and content among tree amino acids during fermentaion. The correlation coefficent between totals of free amino acids and the contents of amino nitrogen were relatively high (0.87