• Korean journal of food and cookery science
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• v.6 no.2
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• pp.85-96
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• 1990

Globefish, Fugu xanthopterus, known to have a severe toxin, is one of the favorite food in Korea and Japan when the toxic part is removed. In this paper, the effect of cooking on the composition of nitrogenous components in the extractives from globefish cooked investigated and the changes of the taste compounds originated from the nitrogenous components in the extractives were discussed. When the sample fish was analysed for general composition, drip amount and pH by the different methods of thawing, the method effective method was the running water thawing. Total nitrogen content in raw globefish and the frozen globefish was not different, and the nitrogen content was increased with the heat treatment. It seemed that the nitrogen content was higher in the extract from the boiled globefish than that of the steamed globefish. Taurine, lysine, glycine and alanine were occupied about 70% of the total free amino acids. Total free amino acid content was higher in the extracts from the frozen sample than those from the raw sample. The amount of free amino acids was increased when the globefish soup cooked under the direct-heat cooking than in the microwave oven-heat cooking. Among nucleotides in the extracts from the thawed and cooked fishes, IMP and inosine contents were increased, and the both components were decreased with the heating time and by the heating method. Tne content of total creatinine-nitrogen were 50% of the total nitrogen content of the extracts, but the concentration of glycinebetaine, TMA and TMAO were only a few amounts. It could be concluded that total creatinine components, including free amino acids such as taurine, lysine, glycine and alanine, and IMP might be the important components contributing to the taste of the cooked globefish.

• Korean Journal of Food Science and Technology
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• v.20 no.6
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• pp.873-877
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• 1988

Nitrogenous extractives and amino acids were analyzed with the dorsal muscle from wild and cultured bastard(Paralichthys olivaceus), and flounder (Pleuronichthys cornutus). Cultured bastard was higher in moisture content, and lower in crude lipid and protein content than those of wild one. Contents of free amino acids from wild and cultured bastard, flounder were 305.03mg/100g, 253.42mg/100g, and 340.10mg/100g, respectively. The profile of free amino acids in these samples was very similar, although there were a relatively difference in glycine, threonine, proline contents. Content of IMP in wild bastard (408.31mg/100g) and cultured one (356.26mg/100g) were higher than that of flounder (178.61mg/100g). Wild bastard contained higher trimeth-ylamine oxide and total creatinine than cultured one. Total amino acid contents of dorsal muscle from wild and cultured bastard, and flounder were 21.94g/100g, 20.12g/100g, and 17.63g/100g, respectively. The major amino acids of these samples were glutamic acid, aspartic acid, leucine and isoleucine.

• Journal of the Korean Wood Science and Technology
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• v.47 no.1
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• pp.80-89
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• 2019

Pine barks are important biomass resources because they are utilised in the production of pine wood and rosins. However, no chemical study has been conducted on the hydrophilic status of pine barks in Indonesia. This aim of this study is to explore the hydrophilic extracts of the barks from six Pinus species (P. elliotii, P. caribeae, P. oocarpa, P. merkusii P. montezumae, and P. insularis). The hydrophilics of pine barks were analysed using gas chromatography-mass spectrometry. The presence of polyphenol contents in the ethanol extracts obtained from the barks of six Pinus species was determined using the tannin-formaldehyde method, Folin-Cioucalteu assay, and vanillin-HCl assay. The ethanol and hot water soluble extractives derived from inner barks were higher in quantity when compared to those derived from the outer bark samples. The polyphenol measurement showed that the highest value of total phenol content was derived from the outer bark of P. montezumae whereas those of the total phenol and tannin- formaldehyde contents were derived from the inner and outer barks of P. oocarpa. GC-MS analysis revealed that nitrogenous compounds are dominant constituents in the inner and outer barks of the six species, followed by sugars and monophenolics, respectively.

• Journal of the Korean Society of Food Science and Nutrition
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• v.24 no.2
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• pp.274-279
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• 1995

Seasonal variation of the taste components such as free amino acids, nucleotides, quarternary ammonium bases, and guanidino compounds in warty sea squirt(S. clava) were determined bimonthly from April to October for its food quality contributed in Korean seafood dishes. Fifty to sixty two percentage of the extractable nitrogen was free amino acids, and mainely it composed of taurine, proline, glutamic acid, glycine and glycinebetaine. Among the various taste component, betaine's level was somewhat higher(11~15%) and nucleotides related compounds also followed(5~8%). Most of nitrogenous compounds in the extractives reached to a maximum value in June and AMP content was relatively higher than the other nucleotides. The major organic acids were composed of succinic acid, malic acid, lactic acid and pyroglutaric acid in S. clava. The result of omission test suggested that the taste of S. clava is mainly attributed to free amino acids, betaines, nucleotides and non-volatile organic acid in order.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.24 no.2
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• pp.123-129
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• 1991

The skipjack and Alaska pollack meat were packed in square No. 3B can, and thermally processed at $121.1^{\cir}C$ so far as to reach Fo values of 5, 10 and 20, respectively. Also the another samples which were heated at $98^{\cir}C$ for 30 minutes were prepared. We have examined the changes of nitrogenous extractives and texture by thermal processing at high temperature in both fish meats. Moisture contents of both fish meats decreased slightly with the increasing of Fo values. When the samples were heated at $98^{\cir}C$ and $121.1^{\cir}C$, pH and VBN contents increased markedly in both fish meats; increasing ratio of pH and VBN contents in skipjack meat was larger than those of Alaska pollack meat. Histamine were detected in concentration of 6.1mg/100g, 0.1mg/100g in raw skipjack and Alaska pollack meat, 8.2mg/100g, 0.1mg/100g in Fo 20 samples of these fish meats, respectively. The contents of total free amino acids in skipjack and Alaska polack meat were 984.8mg/100g, 282.3mg/100g, and these total contents decreased slightly with increasing of Fo values. Little changes were observed in free amino acid composition, but only His, Tau, Ala in skipjack meat and Tau in Alaska pollack meat decreased significantly by heat treatment. Also the degredation of IMP were Proceeded during Preparation and heat treatment of samples, and TMAO changed into TMA almost equivalently. In changes of textures, as compared with heating of 98t for 30 minutes; Fo 5 heat treatment became more softened these fish meats.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.26 no.2
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• pp.150-158
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• 1993

In order to investigate the content and seasonal variation of the extractive components including taste compounds, free amino acids, nucleotides and related compounds, quanternary ammonium bases, and guanidino compounds of ascidian collected from the south coast of Korea were determined bimonthy from April to October in 1990. The extractive nitrogen was composed of $60{\sim}62\%$ as free amino acids, $12{\sim}16\%$ as betaines, $5{\sim}9\%$ as nucleotides, and others as trimethylamine oxide(TMAO) and total creatinine. The muscle of ascidian was rich in such free amino acids as taurine, proline, glutamic acid, glycine and glycinebetaine. Most of nitrogenous compounds in the extractives showed a marked seasonal variation with a maximum in summer or autumn. AMP content was relatively high among nucleotides. Succinic acid, malic acid, lactic acid and pyroglutaric acid were the major organic acids in ascidian. The results of omission test suggested that the taste of ascidian is attributed to mainly free amino acid, betaines, nucleotides and nonvolatile organic acid in order.