• Korean Journal of Food Science and Technology
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• v.8 no.4
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• pp.225-229
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• 1976

Gulbi, salted and dried yellow corvenia, is one of widely consuming fish foods in this country. This study was attempted to establish the basic data for evaluating the taste compounds of Gulbi. The free amino acids were analysed by amino acid autoanalyser. In the free amino acid composition of raw yellow corvenia, abundant amino acids were glutamic acid, alanine and lysine and then leucine, glycine, serine and threonine in order. Such amino acids like proline, valine, methionine, tyrosine and phenylalanine were poor in content. The changes of free amino acid composition in the extract of yellow corvenia during Gulbi processing was not observed. In the extract of Gulbi product, glutamic acid, lysine, leucine, alanine and valine were dominant holding 20.0%, 12.9%, 11.1%, 10.1% and 8.5% of total amino acids respectively. The amounts of total free amino acids of yellow corvenia increased more than 3.6 times as compared with that of raw sample during Gulbi processing. It is convinced that the characteristic flavor of Gulbi was attributed to such amino acids like lysine and alanine known as kweet compounds, as glutamic acid with meaty taste, and as leucine known as bitter taste.

• Journal of Ginseng Research
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• v.9 no.1
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• pp.95-103
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• 1985

The concentrated red ginseng extract (RG-EXT) was prepared by extracting the ginseng tails with 0-90% ethanol solution at 70-100$^{\circ}C$ and analyzed for amino acids composition and other nitrogeneous fractions. The results showed that nonprotein fraction was more than 90% of the total N-compounds and 17 free amino acids were identified by High Performance Liquid Chromatography. Maximum and minimum N-compounds or total free amino acids were recovered in RG-EXT with 50% and 90% ethanol, respectively. An increase in ethanol concentration resulted a significant change in free amino acid composition while extraction temperature caused a little gradual decrease in water soluble nonprotein and total nitrogen fractions.

• The Korean Journal of Ecology
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• v.14 no.1
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• pp.75-85
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• 1991

Changes in the activities of isocitrate dehydrogenase (IDH) and glutamate dehydrogenase (GDH) and changes in free amino acids in the cytoplasm of Saccharomyces cerevisiae have been studied under heat shock condition. Heat shock conditions led to a significant decrease of NAD-IDH and NAD-GDH, It was shown appeared that the meaningful patterns of increase of NADP-IDH and NADP-GDH. It suggested that heat shock in yeast leads to a splitting of the TCA cycle and that glutamate synthesis takes place through the coupling of the NADP-linked isocirate and glutamate dehydrogenase. It was shown that about 14% of total free amino acids of yeast cells was decreased by heat shock. Especially heat shock condition resulted in the marked decreases of serine family amino acids such as serine, glycine and cysteine, and in the considerable increases of the rates of methionine, alanine, glutamin.

• Proceedings of the Korean Society for Food Science of Animal Resources Conference
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• 2004.05a
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• pp.258-261
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• 2004

Sixteen primary free amino acids were determined for each 10 longissimus muscles of Yorkshir, Landrace and Korean native black pig. Eight amino acids at 7 d classified three breeds at ca. 80% confidence. The difference in free amino acids for aged meats could be one of factors responsible for more desirable palatability of Korean native black pig.

• Journal of the Korean Society of Food Science and Nutrition
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• v.12 no.3
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• pp.225-229
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• 1983

The change of free amino acids was identified during fermentation of kimchis (Ixeris sonchifoliaH.) added fermented anchovy. The results were summarized as follows; In fresh roots and leaves of Ixeris sonchifolia H., 8 kinds of free amino were determined respectively. Among them, argine, cysteine and glutamic acid were abundant in fresh roots, while arginine, valine, isoleucine and phenylalanine in fresh leaves, especially arginine was dominant in fresh both roots and leaves. The amount of total amino acids in fresh leaves was about 2.5 times of that of roots. After fermentation, 15 kinds of free amino acids were determined in kimchis, and the characteristic favor of in was attributed to such amino acids as threonine, glutamic acid, alanine, leucine and cysteine. The content of total free amino acids in kimchi leaves was increased to about 5 times of that in fresh (9,435,6mg % on dry base), but in kimchi roots, 11 times of that in fresh was contained (7,079,1mg % on dry base) In kimchi'es extract, 16 kinds of free amino acids were determined, and threonine, glutamic acid, alanine, cysteine and leucine were abundant.

• Journal of the Korean Society of Food Culture
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• v.13 no.1
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• pp.59-64
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• 1998

In order to find causes of the difference in taste between Korean and Japanese soybean paste, comparian was made on the free amino acids composition in soybean paste in those two countries. It was found that the free amino acid composition of commercial soybean paste made in Korea was analogous to homemade soybean paste, and the commercial soybean paste made in Japan, was analogous to homemade soybean paste. And there was a similarity on the point that the glutamic acid content was the highest of all free amino acids content in both Korean and Japanese soybean pastes. There was a difference in the mean total free amino acids content between Korean and Japanese soybean paste. The mean ratio of the glutamic acid content to total free amino acid content in Korean and Japanese soybean paste was on the range of $11.5%{\sim}22.6%$ and $10.4%{\sim}12.5%$, respectively. These results suggest that glutamic acid determines taste in Korean and Japanese soybean paste.

• Journal of the Korean Home Economics Association
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• v.19 no.1
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• pp.25-31
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• 1981

The changes of various nitrogenfractions and free amino acid composition were investigated at various growing stages. The results are summarized as follows 1) Total nitrogen, water soluble protein nitrogen, and true protein nitrogen were decreased with growth. 2) Free amino acid increased with sprout-growth. the content of free amino acid were about 74.4%(combined Ser, Asp, Arg, Val) after 4 day sprout. It is belived that serine, aspartic acid, arginine and valine play an important role as taste compounds in mungbean sprout. 3) 16kinds of amino acid, including essential amino acids in human nutrition except tryptophan and cystin were quantified.

• The Korean Journal of Food And Nutrition
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• v.7 no.4
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• pp.253-258
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• 1994

This thesis is to analyze the ingredients of five-fruit tea depending on extraction time as a basic experiment for quality improvement and industrialization of traditional Korean beverage. According to extraction time, the acidity of the tea is 2.4% at 30 minutes, 2.3% at 50 minutes and 1.7% at 70 minutes, and soluble solid is 0.22 g, 0.31 g and 0.41 g. The pH of five-fruit tea, which is 4.70, 4.85 and 4.98 at each time, and total sugar is 54.01 m9, 108.82 m9 and 142.92 mg as extraction time increases. The total amount of free sugars is 1.14 mg, 1.36 mg and 2.17 mg, and glucose, surcose and fructose which are 98.2%, 92.6% and 92.6% of the whole percentage occupy the most part of free sugars. The total free amino acids content increases to 84.94 mg, 99.67 mg and 120.40 mg. The five kinds of amino acids like serine, glutamic acid, threonine, proline and alanine amount to 94.5%, 93.6% and 94.7% at all. she variation in the percentage of free amino acids content in accordance with extraction time is as follows : threonine, extracted for 50 minutes, is reduced considerably and glutamic acid decreases gradually as extraction time increases. When proline is extracted for 50 minutes, it's rate of increase Is most high.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.34 no.4
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• pp.394-402
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• 2001

In order to investigate the composition of dried layer, Porphyra yezoensis cultured at the south coast of Korea, the dried laver was analyzed separately for extractive nitrogen, free and combined amino acids, ATP and related compounds and quaternary ammonium basis using specimens collected monthly from January to April 1998. The extractive nitrogen contents of dried layer extracts were $976\~1,196\;mg/100\;g$ (on dry basis). Twenty-eight to thirty-one kinds of free amino acids were found in the dried laver extracts and their total amounts were 5,648-6,845 mg/100 g (on dry basis). The extracts were rich in free amino acids such as alanine, glutamic acid, taurine, phosphoserine and aspartic acid. Eighteen to twenty-two kinds of combined amino acids from oligopeptides were found in the extracts and their total amounts were $1,194\~1,406\;mg/100\;g$ (on dry basis). The amounts of ATP and related compounds were $111.6\~195.5\;mg/100\;g\;(3.30\~6.00{\mu}mol/g$ on dry basis). Homarine was detected in all samples but glycinebetaine, $\beta$-alaninebetaine and $\gamma$-butyrobetaine disappeared during processing, TMAO was detected in all samples but low TMA was found in some. During processing of dried layer, P. yezoensis, free amino acids, ATP and its related compounds were increased but the other constituents such as combined amino acids, TMAO and TMA and betaines were decreased in all specimens.

• Korean Journal of Plant Resources
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• v.30 no.6
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• pp.670-678
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• 2017

Persimmon seeds contain considerable amounts of minerals, amino and organic acids, natural antioxidants and phenolic compounds. The objective of this study was to investigate quality characteristics and antioxidant potential of Korean persimmon seeds. The pH (4.88-4.94), color values, contents of minerals, free amino acids, organic acids, and phenolic compounds and DPPH free radical scavenging potentials of persimmon seed extracts significantly (p < 0.05) varied with the genotypes. This study showed that the seeds could be used as a source of different mineral elements (47.14-85.07 mg/kg) without any measureable amount of heavy metals such as arsenic, cadmium, lead and mercury. Similarly, considerable amounts of organic (1550.13-2413.08 mg/kg) and essential amino (50.85-54.03 mg/kg) acids and total phenolic compounds ($1227.91-1307.78{\mu}g$ gallic acid equivalent/g) were also found in the seed extracts, indicating their potential food value as a natural antioxidant. Results of the present study imply that prethanol-A, a food preservative, can be used as an effective extraction to obtain the minerals, organic and free amino acids, and phenolic compounds from the persimmon seeds, which possess a big potential to be commercially used in food, cosmetic and pharmaceutical industries.