• Food Science of Animal Resources
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• v.30 no.3
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• pp.435-442
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• 2010

The study analyzed the effects of salt concentration [high salt (HS) and low salt (LS)] and sodium nitrite ($NaNO_2$), which are typically utilized in Korean processing facilities, on fatty acid composition, free amino acids, microbial counts and sensory characteristics of processed dry-cured ham. Four different treatments were considered: three hams (11.30 kg) salted with 92 g/kg salt (w/w) (HS), three hams (10.65 kg) treated with HS and 100 ppm $NaNO_2$ (HS+$NaNO_2$), three hams (11.42 kg) salted with 62 g/kg salt (w/w) (LS), and three hams (10.62 kg) treated with LS and 100 ppm $NaNO_2$ (LS+$NaNO_2$). Fatty acid composition analysis revealed significantly (p<0.05) higher saturated fatty acid and lower (p<0.05) unsaturated fatty acid in the HS+$NaNO_2$ group compared with the other groups. Glutamate, alanine and lysine free amino acids were higher than the other free amino acids. The processing conditions did not significantly affect the free amino acids of biceps femoris muscles, except for the proline content (p>0.05). In sensory evaluation, the fermentation aroma of the LS group was higher than that of the HS group. The aerobic counts consistently ranged from from $2.3{\times}10^2$ to $1.11{\times}10^4$ CFU/g. Escherichia coli including strain O157:H7, Staphylococcus aureus, and Salmonella spp. were not detected.

• Journal of the Korean Applied Science and Technology
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• v.6 no.2
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• pp.11-19
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• 1989

In order to fractionate sardine oil by different solvents for an effective use of fish oil being subjected to the limit of use, an attempt was to investigate the proper solvents, ratios and fractionation time. The results of the study were as follows: 1. The proper solvent of fractionation using ethanol, isopropyl alcohol, acetone, and hexane was ethanol, and its optimum ratio was 2:1 (ethanol: oil, v/w). The proper time of ethanol fractionation by the ratio (2:1) was 4hr at $10^{\circ}C$, 6hr at $5^{\circ}C$, 8hr at $0^{\circ}C$and 8hr at $-5^{\circ}C$, respectively. 2. In the fractionation by stages using the ratio (2:1) at each temperature, the yield of stearine was 8％ at $10^{\circ}C$ (Fraction I), 32％ at $5^{\circ}C$ (Fraction II), 7％ at $0^{\circ}C$ (Fraction III) and 10％ at $0^{\circ}C$ (Fraction IV), respectively. When ethanol fractionation was undertaken at $5^{\circ}C$ by stages, the yield of stearine (Fraction II) was high. 3. Iodine value of Fraction II was 96.8. This result indicated that the hydrogenation process would be simplified by fractionation. 4. The percentage of the decrease of polyenoic acids from original sardine oil to Fraction II oil was from 30.5％ to 13.5％. The major fatty acids of Fraction II were palmitic and oleic acids and these fatty acids were about 52％ of total fatty acids. Therefore, Fraction II, which remained liquid oil at room temperature because solid fat content was 6.9％ at $20^{\circ}C$, would be used as frying oil.

• Korean journal of food and cookery science
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• v.22 no.1 s.91
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• pp.69-79
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• 2006

Traditional doenjang with Lentinus edodes added at a concentration of 0, 3, 5 and 10% (w/w) was prepared and its physicochemical characteristics were analyzed during fermentation for 6 months. The moisture content, salt level and pH for doenjang were decreased with increasing addition of Lentinus edodes powder, but crude protein content was increased. Among the free sugars, glucose, galactose, arabinose, sucrose and maltose were identified and quantified, with the first two being the major free sugar. Minerals were detected in the order of Na> K> P> Ca> Mg> Fe while the content of Cu, Mn and Zn exhibited little change. The contents of each amino acid of traditional doenjang with added Lentinus edodes, glutamic, leucine and aspartic acids, had a much higher level. In fatty acid compositions, palmitic, stearic, oleic and linoleic acids were analyzed, with oleic acid being the most abundant fatty acid at $56.4{\pm}0.8\sim57.5{\pm}0.5%$ in all the tested samples. GMP and IMP contents of nucleotides and their related compounds were extremely high. It was thought that these substances contributed to the sweet taste of traditional doenjang with added Lentinus edodes. These results showed the applicability and high quality of traditional doenjang with added Lentinus edodes.

• Nutritional Sciences
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• v.9 no.3
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• pp.173-178
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• 2006

The purpose of this study was to investigate the effects of wax gourd on body weight, body fat, triglyceride, leptin and fat cell size in rats fed medium fat Male Sprague Dawley rats were fed with experimental diet containing total dietary fat at 20% of calorie with wax gourd (WG) for 4 weeks. Forty rats were divided into 4 groups including control, 5, 10, and 15% (w/w) WG supplement The results showed that weight gain was significantly higher in 5% WG than that in control (p<0.05), but was not different among the WG supplement groups. Total fat weight was significantly decreased in both 10 and 15% WG supplement groups than that of control. The levels of triglycerides and free fatty acids in the plasma were significantly decreased, particularly in 15% WG supplement group (p<0.05). The levels of leptin was not significantly different among the experimental groups. Fat cell size was significantly decreased in WG supplement groups compared to that of control group (p<0.05). Correlation among the parameters demonstrated that weight gain correlated positively with total fat weight, the levels of leptin and triglycerides. Taken these results together, 15% WG supplement diet substantially reduces total fat weight, triglycerides and free fatty acids levels and fat cell size in the rat fed midium fat.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.20 no.6
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• pp.520-528
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• 1987

Quality stability of roasted lavers during heat treatment and storage was investigated measuring the changes in pigments including chlorophyll a, carotenoids and biliproteins, fatty acids and free amino acids as the major quality factors. In roasting of fried lavers, carotenoids were found to lie more stable than chlorophyll a, and biliproteins were most heat labile. The overall heat stability of the pigments depended upon heating time and temperature. Chlorophyll a and carotenoids were retained more than $90\%$ in the casts of roasting for 90 min. at $60^{\circ}C;\;60min.\;at\;80^{\circ}C;\;10\;min.\;at\;100^{\circ}C;\;or\;5min.\;at\;150^{\circ}C$ while biliproteins remained about $70\%$. The lipids of dried lavers including polyunsaturated fatty acids appeared rather heat stable when compared to the stability of pigments under the same conditions of roasting. Spray of sesame oil or seasoning solutions on the surface of lavers after roasting seemed desirable for stabilizing pigments and free amino acids during storage particularly at low water activity. And that was also benefit for the protection of polyenoic fatty acids from rapid progress of oxidation during storage. Free amino acids were reduced fast during roasting, especially most of threonine and glycine while glutamic acid was rapidly lost during the storage.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.37 no.2
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• pp.185-197
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• 1992

Differences in the amount and chemical characteristics of the epicuticular waxes on rice leaves were studied for the active tillering and heading stages of rice varieties differing widely in gross leaf-surface property and genetics. The amount of waxes on surfaces of rice leaf-blades was determined by extraction with chloroform and chemical composition of the waxes was characterized by thin layer chromatography, gas liquid chromatography and infrared spectrophotometry. The amount of waxes varied by variety and significantly with growth stage. The amount at the heading stage was 1.7 to 3.6 mg/g fresh weight of leaves, which was two to three times as much as that at the tillering stage of 0.8 to 1.8 mg/g fresh weight. The waxes consisted of seven chemical classes, namely diols, fatty acids, fatty alcohols, fatty aldehydes, fatty esters, saturated and unsaturated hydrocarbons. Diols and unsaturated hydrocarbons were identified as new chemical classes of the rice epicuticular waxes. The polar constituents such as dials, fatty acids and fatty alcohols and the non-polars such as fatty aldehydes, fatty esters, and saturated and unsaturated hydrocarbons were identified at the heading stage, but at the tillering stage only the non-polar compounds were identified. In the carbon numbers (C) of the chemical classes, diols were composed entirely of C30 and acids were mainly of C30 and C31. In alcohols, primary alcohols were composed of C13 and C32, and the secondary alcohols were of C14, C16 and / or C30 regardless of the rice varieties. The acid portion of fatty esters, mainly composed of C22 and C23, showed low cabon numbers compared with the aldehydes. The alcohol portion of them showed a wide distribution in carbon numbers from C13 to C26 depending on the rice varieties. Hydrocarbons had odd carbon numbers, consisting mainly of C29 and C31.

• Journal of the Korean Society of Food Science and Nutrition
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• v.11 no.4
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• pp.37-41
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• 1982

In order to determine the optimal condition for making Yugwa (one of the Korean traditional cake) the textures in various conditions were studied by sensory test and texturometer. The changes of texture and fat content in the cake were measured along the period of storage. The results were as follows: (1) The cake were classified in 3 groups according to the leavening agent used in the procedure, namely refined rice wine (W), distilled liquor (L) and yeast group (Y). It was the refined rice wine group that had been 'the best' by sensory test. Its brittleness $(1.40{\pm}0.27)$ was higher than those of L and Y. (2) Crispness measured by bend test prior to soaking into syrup were 1.19, 1.23 and 1.63 in W, L, Y, respectively. (3) Chemical composition (%dry basis)) of Yugwa leavened with W included 9.3 of moisture, 1.3 crude protein, 6.7 crude lipid, 66.4 carbohydrate and 16.3 crude ash. (4) Brittleness decreased gradually along the period of storage while the rancidity increased. From the 40th days of storage, the change of brittleness and rancidity were marked as well as the scores of sensory test decreased significantly. (5) Content of linoleic acid in Yugwa decreased along the period of storage from 52.5% of total fatty acid on the first day to 10.9% on the 50th days Main fatty acids in Yugwa were oleic acid, palmitic acid and stearic acid, all of which were also decreased in content along the period of storage. One remarkable change was the appearance of an unknown fatty acid with 19.54 of retention time, in 50% of total fatty acid, on the 50th day of storage.

• Journal of Nutrition and Health
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• v.20 no.5
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• pp.330-340
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• 1987

Young mae rats were fed fro 4 weeks on different experimental diets containing 8%(w/w) fat ; sardine oil, soybean oil and lard. In the sarine oil group, total cholesterol and triglyceride concentrations inplasma were significantly lower than in the soybean oil and lard group. The proportion of $\omega$-3 polyunsaturated fatty acids in erythrocyte membrane phospholipids were significantly higher in the sarine oil-fed animals. by sardine oil ingestion, lipid peroxide levels inthe plasma and liver were elevated while $\alpha$tocopherol concentrations were lowered, compared to the other groups. However, erythrocyte osmotic fragility was unaffected by the different fat diets.

• Food Science and Preservation
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• v.17 no.4
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• pp.533-540
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• 2010

Overall composition, and fatty acid, amino acid, and nucleotide-type compound levels in wild (Haliotis gigantea) and cultured abalone (Haliotis discus hannai), were investigated. Wild abalone had a higher moisture content than did cultured abalone, but the converse was true for crude protein content. In overall composition, crude lipid level was higher in the viscera than in the meat, with the greatest level, $2.02{\pm}0.15%$ (w/w), observed in the viscera of wild abalone. The major fatty acids were palmitic acid (16:0), oleic acid (18:1n-9), eicosatrienoic acid (20:3n-3, ETA), eicosapentaenoic acid (20:5n-3, EPA), and docosahexaenoic acid (22:6n-3, DHA). The omega-3 fatty acid content (EPA and DHA) was higher in wild than in cultured abalone. A total of 17 amino acids were detected in all abalone samples, most of which had high levels of aspartic acid, glutamic acid, glycine, and arginine, and low amounts of cysteine, methionine, and histidine. Glutamic acid was the most abundant of all amino acids. The content of free amino acids was related to taste score. The major free amino acids were taurine, alanine, and arginine, of which taurine was the most abundant, and was present at higher levels in wild compared to cultured abalone. The total contents of nucleotide-related compounds in wild and cultured abalone were 12.93 mg/100g and 30.75 mg/100g, respectively.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.47 no.1
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• pp.31-38
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• 2014

Docosahexaenoic acid (DHA, 22:6n-3) and ecosapentaenoic acid (20:5n-3) have attracted increasing attention since the first epidemiological report on the importance of n-3 essential fatty acids. It is thought that DHA has important functions in brain and retinal tissues. Thraustochytrids, a group of marine protists, are capable of heterotrophic growth, and are potential omega-3 producers for industrial use, especially the members of the Schizochytrium and Thraustochytrium genera. The aims of this work were to isolate, identify and screen thraustochytrids from 17 different locations. Twenty-three isolates were screened for biomass, total fatty acid (TFA) and DHA content. Analysis of the fatty acid methyl esters revealed four distinct clusters biomass ranged from $8.68-9.36gL^{-1}$, and lipid and DHA contents ranged from $3.11-4.10gL^{-1}$ and $1.05-1.93gL^{-1}$ biomass, respectively. B-12 isolates were screened for biomass ($9.36gL^{-1}$), TFA ($4.10gL^{-1}$) and DHA (47.01%, w/w) content. C-6 isolates were also screened for biomass ($8.92gL^{-1}$), TFA ($3.30gL^{-1}$) and DHA (49.41%, w/w) content. The 18S rRNA gene sequencing results identified Schizochytrium mangrovei as B-12 and Crypthecodium cohnii as C-6.