• Korean journal of food and cookery science
• /
• v.14 no.3
• /
• pp.250-254
• /
• 1998

A variation of free sugar and amino acid contents of pears during the ripening period was determined by HPLC and amino acid analyzer. The research results are as follws: Fructose, glucose and sucrose were present in the pears. The contents of fructose was the highest, followed by glucose and sucrose in order. The contents of total sugar in Shingo and Youngsan was similar, but the contents of frucose in Shingo was lower and the contents of sucrose was higher than that of Youngsan (p＜.001). During the ripening period, the contents of fructose and glucose gradually increased during the harvesting season and then somewhat decreased. The contents of sucrose increased continually, while the contents of total free sugar reached the maximum during the harvesting season, it was 10.41%, 10.29% in Shingo and Youngsan and then decreased gradually. The contents of total free amino acid in Shingo was higher than that of Youngsan. A variation ratio and the composition of amino acid in Shingo and Youngsan during the ripening period didn＇t make a significant difference. The major free amino acid of the pears was in the order of aspartic acid, serine, threonine, histidine, glutamic acid, valine, arginine, and alanine. During the ripening period, aspartic acid, threonin, serine, methionine, isoleucine, leucine, histidine, and Iysine increased gradually. Glutamic acid, alanine, valine, arginine didn＇t show much change. The contents of total free amino acid increased during the ripening period.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.23 no.6
• /
• pp.933-938
• /
• 1994

A study was amino acid contents by heating conditions of mackerel, pacific saury , yellow croaker, and brown sole investigated. In fresh fishes, total amino acid contents showed higher amount in brown sole and yellow croaker, than those of pacific saury and mackerel. The amino acid contents among the tested samples were higher Glx , leucine, lysine and arginine in order. During heating of samples the amino acid contents decreased. There appeared to be a proportional relationship of the heating temperature to decrease of amino acid. The amino acid contents of steamed samples significantly decreased than those of others. During warming and rewarming samples after storage at 4$^{\circ}C$ for 24 hours , amino acid contents slightly decreased.

• Journal of the Korean Society of Food Culture
• /
• v.19 no.3
• /
• pp.348-358
• /
• 2004

This study was conducted to examine contents of total acid and free amino acids in the Demi-glace with added quantity of Omija extracts. Firstly, The level of Total acid content of Demi-glace sauces was $1.08{\sim}1.89%$ and Omija extracts was $2.77{\sim}7.24%$. The more Omija extracts added, there was the higher total acid contents. Sauces and extracts of 5% Omija was the highest. Secondly, Total free amino acids contents of control was 2518.52mg%, and Omija sauces was $2261.52{\sim}2894.14mg%$. 2% Omija sauces was the highest among them. Hydroxyproline of total 34 free amino acids was the highest, and Glutamic acid 158.42mg%, Proline 78.90mg% was next in order. Arginine was the highest with $27.40{\sim}34.40mg%$ among 9 essential amino acids contents. Glutamic acid was the highest contents with $123.18{\sim}158.42mg%$. Compared to control's(0.41mg%), Omija added group was $20.63{\sim}27.82mg%$ and it was the highest increase. While other 15 amino acid was analyzed, Hydroxyproline was the highest contents with $1,737.22{\sim}2,205.80mg%$. Compared to control group(15.63mg%), proline was $57.01{\sim}78.90mg%$ Omija added group and it was increased with the highest contents. In essential amino acid, flavor enhancing amino acid and other amino acid were increased and the highest contents with 2% added Omija sauce. Thirdly, sensory characteristics of Demi-glace sauces based on overall preference, It was find that 2% added Omija was the best. 2% added was the best for color, flavor, taste, texture, overall acceptability(P<.001). In terms of Demi-glace sauces' gender preference, male and female people liked 2% added Omija color, flavor, taste, texture, overall acceptability. It was find that there was no significant differences between male and female.

• Biomolecules & Therapeutics
• /
• v.3 no.1
• /
• pp.91-96
• /
• 1995

The effects of toluene inhalation on the contents of amino acid neurotransmitters in rat brain were investigated and blood toluene concentrations inducing changes of behavior and amino acid neurotransmitter contents in rat brain were observed. Male wistar rats were exposed to toluene vapor (single dose : 1700, 5000 and 10000 ppm for 2 hrs, repeated dose : 1700 and 5000 ppm for 2 hrs/day$\times$6 days). Toluene concentrations in blood and the inhalation chamber were assayed by GC with headspace sampler. HPLC method following PITC derivatization was used to measure the amino acid contents in brain tissues such as frontal cortex, caudate, hippocampus, cerebellum and brain stem. Glutamic acid and aspartic acid levels were increased by single inhalation of toluene (5000 ppm) in all the brain areas assayed in this experiment. In caudate and cerebellum, taurine levels were decreased by single inhalation of low dose toluene (1700 ppm), but increased by repeated administration. At high blood toluene concentration, GABA levels were increased in all the brain areas assayed in this experiment and the increasing extents of inhibitory amino acid contents measured in caudate and hippocampus were greater than those of excitatory amino acids. These results suggest that the changes of amino acid neurotransmitter contents in brain by exposure to toluene may modulate toluene-induced behaviors.

• Food Science of Animal Resources
• /
• v.37 no.5
• /
• pp.626-634
• /
• 2017

This study set out to identify the changes in the nutrient contents during the chicken cooking process as basic data for the establishment of a national health nutrition policy. Samples were produced using 3 chicken parts (wing, breast, and leg) and 7 cooking methods (boiling, pan-cooking, pan-frying, deep-frying, steaming, roasting, and microwaving), and the essential amino acid contents, principal components, and retention rates were analyzed. Weight loss was observed in all chicken parts with all cooking methods. The protein and essential amino acid contents of the chicken samples differed significantly according to the part and the cooking method (p<0.01). The protein and essential amino acid contents (g/100 g) of raw and cooked chicken parts showed ranges of 16.81-32.36 and 0.44-2.45, respectively. The principal component analysis (PCA) clearly demonstrated that the cooking methods and chicken parts produced similar trends for the essential amino acid contents. The retention rates of the chicken parts varied with the cooking methods, yielding a minimum value of 83% for isoleucine in a roasted wing, 91% for protein in a steamed breast, and 77% for isoleucine and lysine in a roasted leg. Therefore, the protein and amino acid contents of the roasted breast were higher than those of the other cooked chicken parts.

• The Korean Journal of Food And Nutrition
• /
• v.12 no.5
• /
• pp.496-501
• /
• 1999

Albinism is a phenomenon that color of the body surface is changed to white orfaint brown from the specific color to the species by difficiency of pigments due to mutation or disease. This study was undertaken to investigate the experimental basis on the appearance of albinism in cultured flounder Paralichthys olivaceus. The skin and muscle from the normal and albinic flounder were used by measuring contents of amino acid free amino acid. The results were summarized as follows: Contents of amino acid in theskin and muscle are different from normal and albinic flounder. Phenolic and sulfuric amino acids in the skin of normal flounder were 2 times those of albinic ones. Especially tyrosine contents of the skin in normal flounder were 24 times higher than those. Methionine was 26 times higher than those Phenylalanine was 1.6 times higher. In free amino aicd phosphoserine and phosphoethanolamine were a little higher than that ones. The melanin formation of the skin in flounder was affected by substrates such as phenolic amino acid and cofactor such as sulfuric amino acid.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.18 no.4
• /
• pp.333-338
• /
• 1985

In this experiment, the contents of free amino acids, and nucleotides and their related compounds of dried cod products were analysed by amino acid autoanalyzer and HPLC. Proline, histidine, lysine and alanine were dominant amino acids in raw extracts, having $65.4\%$ of total free amino acid contents, but the contents of aspartic acid, serine, isoleucine and phenylalanine were low, and methionine, tyrosine and arginine were detected in trace amount. In free amino acid composition of dried products, abundant amino acids were glycine, histidine, lysine, proline and alanine. Such amino acid as aspartic acid, methionine, tyrosine and phenylalanine were poor. In extracts of storage sample, most free amino acids were increased in both sun dried products and hot air dried products, and glycine, histidine, lysine, proline and alanine were abundant amino acid, such amino acid as methionine, tyrosine and phenylalanine were poor. In raw cod, inosine and IMP were dominant contents which 18.5, $10.0{\mu}mole/g$ on dry base, respectively, but the contents of ATP, ADP, hypoxanthine and AMP were detected less than $3.2{\mu}mole/g$. ATP and ADP were decreased while IMP, inosine and hypoxanthine were increased during drying and storage of cod.

• Korean Journal of Agricultural Science
• /
• v.45 no.3
• /
• pp.379-384
• /
• 2018

In this study, we analyzed the amino acid contents of corn to provide basic data for promoting the use of proteins in livestock. The present study was done to examine the amino acid contents of the corn 'Gwangpyungok' grown in a natural field at the National Institute of Animal Science, Cheonan province, Korea, in 2016. Gwangpyungok, which is Korean corn cultivar, was used as the sample to provide basic data for promoting the use of proteins in livestock by analyzing the amino acid contents of each part of corn as a breed that is adaptable to the environment of Korea. The asparagine acid content was the highest in the leaf blade among the parts of corn, and the glutamic acid content was the highest in the corn ear, stem, leaf sheath, corn bract and inflorescence. The essential amino acids in the corn ear, leaf blade and inflorescence revealed that their contents were in the following order: leucine > phenylalanine > valine > threonine > lysine > isoleucine, and in the inflorescences and stem, leaf sheath and corn bract, their contents were in following order: leucine > valine > phenylalanine > threonine > lysine > isoleucine. Therefore, further research on the nutritional aspects of forage must be performed because livestock growth is influenced by the nutritive value of the various parts of forage.

• Journal of the Korean Society of Food Culture
• /
• v.12 no.2
• /
• pp.149-153
• /
• 1997

A variation of free sugar and free amino acid contents of apples during the ripening period was determined by HPLC and amino acid analyzer. The research results are as followes: Fructose, glucose and sucrose were present in the apples. The contents of fructose was the highest, followed by the order of sucrose and glucose. The contents of total sugar in Red fuji was relatively higher than that of Fuji. During the ripening period, the contents of fructose increased conspicuously for the harvesting season and then it decreased gradually. The contents of glucose increased gradually for the harvesting season and then it somewhat decreased. The contents of sucrose increased continually, while, the contents of total free sugar reached the maximum for the harvesting season and then it decreased gradually. A variation in the contents of free amino acid and composition during the ripening period didn't make a significant difference. The major free amino acid of the apples was in the order of aspartic acid, serine, threonine, glutamic acid, histidine, arginine, and alanine. During the ripening period, aspartic acid, threonin, serine, alanine, histidine, and arginine increased gradually. Especially, alanine, histidine, and arginine increased remarkably after the the harvesting season. Glutamic acid, valine, isoleucine, and leucine didn't show much change. The contents of total amino acid increased little by little as the apples ripened, dranstically increased during the harvesting season and slowly increased or slightly decreased after the harvesting seasom.

• KSBB Journal
• /
• v.4 no.2
• /
• pp.157-161
• /
• 1989

The contents of total amino acid and free amino acid in the protein of yellow corvenia were analysed quantitively by HPLC. The results were as follow; The contents of free amino acid of yellow corvenia flesh and yellow covenia roe were 323.0mg/100g and 932.5mg/100g, respectively. The contents of total amino acids of yellow corvenia flesh and yellow covenia roe were 33,2620.0mg/100g and 64,861.0mg/100g, respectively. The contents of essential amino acid of yellow corvenia flesh and yellow corvenia roe were 12,196.0mg/100g and 13,143.0mg/100g, respectively.