• Korean Journal of Fisheries and Aquatic Sciences
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• v.46 no.6
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• pp.717-724
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• 2013

To characterize the food components of two mussels (wild hard-shelled mussel (HM) Mytilus coruscus, and cultured sea mussel (SM) Mytilus edulis) in Korea, we examined the proximate composition, fatty composition, amino acid/mineral content, texture, collagen content and chemical and taste compounds. Regarding the proximate composition, HM had lower moisture levels and higher crude protein and carbohydrate contents than SM. The amino nitrogen, volatile basic nitrogen and total amino acid contents of HM and SM were 250.6 and 227.3 mg/100 g, 11.2 and 12.0 mg/100 g, and 17,451.1 and 15,334.8 mg/100 g, respectively. The major amino acids were glutamic acid, aspartic acid, glycine, alanine, lysine and arginine. The major fatty acids of HM and SM were 14:0, 16:0, 16:1n-7, 20:5n-3, and 22:6n-3, which did not differ significantly between the two mussels. HM had a higher n-3 polyene ratio, and a lower saturate and monoene ratio than SM. Regarding the taste-active compounds, the free amino acid contents of HM and SM were 1,116.5 and 961.8 mg/100 g, respectively, and the major free amino acids were taurine, glutamic acid, glutamine, glycine, citrulline, lysine and arginine. The primary minerals in both HM and SM were Na, Cl, K and P which did not differ significantly between the two mussels. The soluble and insolube collagen contents of HM and SM were 265.8 and 228.4 mg/100 g, and 119.5 and 121.8 mg/100 g, respectively.

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

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.2
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• pp.267-273
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• 2010

The objective of this study was about physicochemical characteristic of puffer muscle and skin to promote the utilization of puffer as fish protein. In proximate composition, crude protein of dried puffer muscle and skin powders were 89.5% and 82.7%, respectively. Skin powders had higher lipid contents than muscle powders. Ash contents of muscle powders were higher than those of skin powders. In nucleotides and their related compounds, the contents of nucleotides were in order of IMP and ADP. The contents of saturated fatty acid in puffer muscle (83.9%) was higher than skin powders (66.3%). Oleic acid, mono-unsaturated fatty acid, in skin powder (25.9%) was higher than in muscle powders. Seventeen kinds of composition amino acids were detected in muscle powders, while 16 kinds of amino acids were found in skin powders. Total contents of amino acid in muscle powders (83,739 mg/100 g) were higher than those of skin powders (75,361 mg/100 g). In the muscle powders of puffer, glutamic acid was the highest amino acid with the concentration of 13,707 mg/100 g, and was in order of aspartic acid, lysine, leucine, arginine, alanine, valine and glycine. In skin powders, glutamic acid was the highest content with 14,843 mg/100 g followed by proline, alanine and arginine. Twenty five kinds of free amino acids were detected in dried muscle powders, while 22 kinds of free amino acids were found in dried skin powders. Taurine of dried puffer muscle and skin powders was the highest free amino acid with the concentration of 554.4 mg/100 g and 153.6 mg/100 g, respectively. The contents of total free amino acids of dried muscle powders were higher than those of dried skin powders. Especially, cysteine was only detected in dried muscle with the content of $159.3\pm1.8$ mg/100 g.

• Journal of Food Hygiene and Safety
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• v.19 no.1
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• pp.31-37
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• 2004

This study was performed to investigate the changes of amino nitrogen, total amino acids, free amino acids, and cole. of traditional Korean soybean paste (doen-jang) during the ripening and storage for 12 months. All of the preparation methods for soybean paste followed the recommendations of the Korea Food Research Institute. The components of soybean paste were analyzed at 0, 6, and 12 months. The content of amino nitrogen of soybean paste was significantly higher than that of soybeans or meju (soybean cakes) at the initial stage of storage (p〈0.05), and decreased during the storage. The composition of total and free amino acids and their ratios of soybean paste were changed during the storage. The ratios of free to total amino acids of soybeans, meju, and soybean paste were 0.8%, 17.3%, and 20.4∼32.9%, respectively. Glutamic acid, which represents the savory taste, was detected the most abundantly in soybean paste during the storage. The ratios of free to total amino acids of glutamic acid were 21.1∼41.5% in soybean paste. Lightness, redness and yellowness of Hunter color of soybean paste decreased over time (p〈0.05). The results of this study indicate that the ratios of fee to total amino acids of soybean paste were much higher than those of soybeans, although its contents of total amino acids were much lower than those of soybeans. The results also indicate that this comes from the preparation and fermentation of meju. It was suspected that the organoleptic quality of soybean paste derived from these three components might be inferior over 1 year of storage time.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.35 no.6
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• pp.666-670
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• 2002

To investigate changes of components in salt-fermented sardine, Sardinops melanostictus sauce during 18 months fermentation, various chemical properties were examined at 2$\~$3 months intervals. The degree of hydrolysis increased sharply until 5 months of fermentation and showed the gentle increasement after that. On the other hand, the contents of total and amino nitrogens, total ATP related compounds increased gradually during 18 months of fermentation. The hypoxanthine and uric acid were abundant in ATP related compounds, ranging from $75\%$ to $87\%$. The contents of inosine+hypoxanthine and uric acid were crossed at 13.9 months of fermentation. After 18 months of fermentation, sauce was rich in free amino acids, glutamic acid, aspartic acid, lysine, alanine, threonine in that order.

• The Korean Journal of Community Living Science
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• v.13 no.1
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• pp.41-49
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• 2002

The purpose of this study is to evaluate the sensory characteristics and the taste components of Korean soybean paste (doenjang) with mushrooms such as Lentinus edodes, Ganoderma lucidum and Phellinus Lentinus. edodes doenjang turned out to have a good taste, odor and color, but Ganoderma lucidum and Phellinus liteus doenjang were worse than control doenjang in the taste, odor and color as well as in sensory evaluation. The contents of amino type nitrogen were higher in Lentinus edodes and Phellinus liteus doenjang than in control doenjang. Of organic acids, succinic acid was the most abundant and Ganoderma lucidum doenjang had a little higher acetic, butyric and propionic acid. Fructose and glucose were detected as free sugar of mushroom doenjang, of which glucose was considerably contained in Ganoderma lucidum doenjang, Total contents of free amino acid were 2.247 ∼ 2.833mg/100g in doenjangs added mushrooms. Glutamic acid and alanine were dominant in mushroom doenjangs.

• Korean Journal of Food Science and Technology
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• v.54 no.2
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• pp.228-234
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• 2022

Various types of tea have been cultivated to obtain different flavors and enhance their functional properties. The objective of this study was to investigate the physicochemical properties of γ-aminobutyric acid (GABA) teas produced from commercial Korean green, white, and black teas. The concentration of total minerals was reduced in GABA green tea and GABA white tea but was improved in GABA black tea. The essential, non-essential, and total free amino acid contents were remarkably increased in the GABA teas. The amino acid GABA content was increased by 561.00 and 294.20 times in GABA white tea and GABA black tea, respectively. The antioxidant potential was not reduced, although the total polyphenol and total flavonoid contents decreased in GABA green tea and GABA black tea. The results indicated that the overall nutritional value of commercial green, white, and black teas could be improved by processing them into GABA teas.

• KSBB Journal
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• v.7 no.3
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• pp.186-190
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• 1992

The compositions of amino acid in the protein and total fatty acid of Dendrolimus spectabilis were analyzed quantitatively by HPLC and GC, respectively. The contents of crude oil and protein from the extracts were 21.00% and 58.47%, respectively. The amount of free amino acids in the protein was 3.65g/100g, and 1.31g/100g of essential amino acids was contained in the free amino acids. The amount of total amino acids in the protein was 41.20g/100g, and 14.75g/100g of essential amino acids were contained in the total amino acid. The compositions of fatty acid in the oil were $C_{18}$=26.81%, $C_{16}$=19.09%, $C_{18:1}$=18.74%, $C_{18:3}$=15.33%, $C_{16:1}$=7.29%, $C_{20}$=5.21% in order, respectively. 45.88% of unsaturated fatty acids were contained in the oil.

• Food Science and Preservation
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• v.5 no.1
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• pp.57-63
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• 1998

To furnish basic data about the utilization of Korean loquat as flood, this experiment was conducted. Nutritional components in leaves, fruit excluded seed, flesh and seed of Korean loquat were analyzed as follows : moisture 48.7%, 87.8%, 88.3% and 59.5% ; total sugar 1.57%, 7.21%, 7.36% and 2.41% ; crude protein 5.23%, 1.61%, 1.44% and 4.31% in each portion, respectively. The highest mineral contents of loquat leaves, fruit excluded seed, flesh and seed were Ca 2,458ppm, K 661ppm, 654ppm and 1,528ppm, and water soluble vitamins such as ascorbic acid, thiamin and pyridoxine were confirmed in different pares of Korean loquat, the contents of those were high thiamin 5.86mg% in leaves and ascorbic acid 1.l0mg%, 1.26mg% and 4.90mg% in fruit excluded seed flesh and seed, respectively. The contents of free sugars were high sucrose 0.87%, glucose 0.62%, 0.6475 and rhamnose 0.20%, and major organic acid were detected oxalic acid 1,693.70mg%, malic acid 201.70mg%, 207.60mg% and citric acid 55.70mg% in each portion, respectively. Free amino acid were identified 21, 14, 14 and 16 kinds of leaves, fruit excluded seed, flesh and seed, respectively and their contents in each portion were highest glutamic acid 280.22mg%, proline 35.l0mg%, glutamic acid 56.96mg% and sarcosine 230.24mg%, respectively. Volatile components were identified 25 and 11 kinds of leaves and flesh and their contents were highest d-nerolidol 28.70ppm, hexadecanoic acid 16.67ppm, respectively.

• Journal of the Korean Society of Food Science and Nutrition
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• v.27 no.6
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• pp.1077-1085
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• 1998

The effects of yeast on the fermentation of kimchi were investigated. The treatments were divided into two groups; yeast treatment during salting of Chinese cabbage(YS) and yeast treatment added in kimchi preparation(YF kimchi). The edible periods of the kimchi after yeast treatment during salting (YS kimchi) was extended 4~5 days by the results of pH, acidity, sensory quality. The activities of amylase, polygalacturonase and galactosidase of YS kimchi were retained at low levels compared to non treated condition throughout all fermentation periods, whereas protease activity was not significant different from the non treated condition. In addition, the contents of total hexose and uronic acid did not show remarkable change throughout fermentation, but total pentose was decreased by more than 7% at the early middle stage of fermentation(7~14 day after soaking). The change of free amino acid content was decreased by 16~44% than the non treated condition. In contrast, in the YF kimchi, the sensory quality was not good. The activities of amylase, protease, polygalacturonase and gal actosidase were appreciably higher than that of the non treated condition. Meanwhile, the contents of total hexose, total pentose and uronic acid, as products of degradation of cell wall constituents by the above enzymes, were decreased by 18~68% throughout fermentation than the non treated con dition, and total free amino acids were higher than the YS kimchi. Thus, yeast treatment during salting was found to be more effective to extend the edible periods of the kimchi.