• Korean Journal of Fisheries and Aquatic Sciences
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• v.8 no.2
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• pp.90-100
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• 1975

The estimation of the pre-processing condition of oyster is of great importance for distributors and processors. This study was attempted to establish the basic data for evaluating the processing suitability of oyster, which is the most important shellfish for domestic use and export. The data were analysed by measuring the condition index, chemical composition and heavy metal content of oysters. In order to eliminate the manual work that has to be done on a tightly closed oyster shell and avoid shrinkage in the oyster meat which is attendant on the steaming process, chemical means to open oyster were examined. finding the method of pretreatment of polyphosphate for frozen oysters were attempted to improve the product quality. The prevention of undesirable color change of the canned oyster meat is another problem to solve. The important results are as follows : 1. The ratio of meat volume and meat weight to the holding capacity by shells may be useful as an index to measure the condition index of oysters. 2. As a whole, monthly changes of moisture and fat content in oysters were reversely correlated. Protein content slightly decreased from April and rapidly decreased in July, and again rapidly increased in August but from September to November decreased slightly. In April, the content of glycogen was 4 percent. From this period to September, glycogen was rapidly decreased. From July to September, it was only 0. 7 to 1 percent but increased from October. There were little seasonal changes in pH value. The pH value of oyster meat was 6.0 to 6.2. The crude ash content was slightly decreased from June to August. 3. The range of monthly change of heavy metal content are as follows: Total mercury was 0 to 0.019 ppm, cadmium was 0.026 to 0.053 ppm, copper was 0.111 to 0.594 ppm, and lead_was 0.061 to 0.581 ppm. 4. By the results of condition index, chemical composition and heavy metal content of oysters, the suitable harvest season as raw materials for processing was the end of December to the end of May of next year. 5. The pretreatment of 10 percent polyphosphate in 5 percent salt solution of oyster meat appeared effective to reduce thawing drip during cold storage. 6. The pretreatment of $Na_2EDTA$ and BHA did not show the color prevention effect to the canned oyster meat during storage. 7. Magnesium chloride affected to open the valves of oysters.

• Journal of the Korea Organic Resources Recycling Association
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• v.6 no.1
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• pp.75-85
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• 1998

Algal meal (cell) was produced from the solution of dairy cow wastes by fermentation of ulothrix. sp. and chlorella sp. Raw wastes mainly feces were diluted with ground water to give dry matter concentration of 0.5 w/v of wastes in 20 l amounts of ten plastic containers. Each containers were covered with plastic nets and vinyl films to protect from the insects and rain. Algea cells were harvested every 3 to 5 days and dried by sunlight and artifitial heat. Dried cells were ground by a feed meal, and analyzed and tested for the chemical composition of dry cell, in vitro DM and protein digestibility and the safty of algae. Protein contents in algae meals, ulothrix (29.37%) and chlorella (29.24%) were similar. However, chlorella contained lower Neutral detergent fiber (5.92%) than ulothrix(20,76%), and higher ash (32.86%) and calcium (12.62%) than ulothrix (28.66% and 6.09%) (P<.01). Ulothrix protein had higher for essential amino acids; valine, isoleucine and phenylalanine, than chlorella (P<.05). Algal fats contained high saturated fatty acids, C16:0 and C18:0, for ulothrix and high unsaturated fatty acids, C18:1 and C18:2, for chlorella (P<.01). In vitro digestibility of. ulothrix tended to be higher for DM, but lower for protein than chlorella. The weight gain and survival percentage were higher for pond fishes (loaches, Misgurnus sp. ) fed diet added chlorella meal than diets added ulothrix meal and control diet (P<.05).

• Korean Journal of Agricultural Science
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• v.8 no.1
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• pp.117-125
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• 1981

The changes in chemical compositions of chestnuts were tested during processing in order to elucidate the effects of heat treatments such as boiling, steaming and roasting on the flesh compositions. The results obtained were as follows. 1. The chemical compositions of raw chestnuts were: moisture, 59-61%; total sugar, 24-27%; crude fat, 0.3%; crude fiber, 0.6-0.9%; ash, 1.0%; amino nitrogen, 0.3%; vitamin C, 20-22 mg%; and tannin, 40-48%. 2. The moisture contents were increased to 63.8% by the boiling and to 70.27% by the peeling and boiling from 59.41% of raw ones respectively, whereas decreased to 54.11% by the roasting. 3. Contents of crude protein were decreased to 8.04% by the peeling and boiling procedure from 8.72% of raw ones, and those of amino nitrogen also revealed a decreasing tendency by the heat treatments. However, no significant change was observed in crude fat content. 4. Total sugar contents were decreased by the peeling and boiling procedure approximately 3.0%, whereas reducing sugars were increased 2 to 3 times in the all treatments. 5. Vitamin C contents were decreased 72.0 to 78.0 % by the boiling procedure, 64.2% by the steaming, 51. 6% by the roasting as compared with the raw ones. Tannin contents were increased 11.0% by the boiling, and 46.0% by the roasting respectively, whereas decreased 22.0% by the peeling and boiling procedure. 6. The color was changed to brown with different degree, during the boiling, steaming and roasting procedure. The 0.1% solution of alum appeared to be effective in reducing the browning reaction during the heat treatments.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.10 no.1
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• pp.1-9
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• 1977

The purpose of this study is to complish a method of fish glue malting with residual products such as fish head and skin discarded from sea food processing. Using the skins of Alaska pollack and file fish from fillet packers, the optimum conditions of skin glue processing were investigated and physical and chemical properties of the product were also determined. The yields of Alaska pollack, Thelagra calcogramma, skin and file fish, Novodon modestus, skin to the total body weight were $4.6\%\;and\;5.0\%$ respectively. The optimum conditions for a $49.3\%$n yield Alaska pollack skin glue processing were considered the extraction of previously tinted in $0.1\%$ calcium hydroxide solution for 3 hours with the additional water as much as 3 times of sample weight at $70^{\circ}C$ for 3 hours under the controlled pH 5.0. The conditions for file fish skin glue were similar to those of Alaska pollack except the addition of five times of water to the weight of sample skin needed for extraction. The content of crude protein of Alaska pollack and file fish skin glue were $98.0\%\;and\;96.0\%$ respectively. The contents of crude ash and crude lipid were not different from that of chemical grade gelatin. Relative viscosity, melting point, gelation temperature and jelly strength of Alaska pollack skin glue marked 5.84, $21.8^{\circ}C,\;7.1^{\circ}C\;and\;10.0g$ respectively and those of file fish skin glue showed $5.79,\;25.0^{\circ}C,\;7.4^{\circ}C\;and\;11.6g$ respectively.The color and turbidity of Alaska pollack skin glue are slightly superior to those of file fish skin glue. It is supposed that the extract residue of skin glue is valuable for use the animal feeds by the results of amino acid composition. And the ratio of each amino acid content to the total amino acid of Alaska pollack and file fish skin glue is similar to that of chemical grade gelatin.

• The Korean Journal of Food And Nutrition
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• v.17 no.3
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• pp.294-301
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• 2004

Effects of superoxide dismutase(SOD), catalase(CAT), and such other proteins as bovine serum albumin(BSA), ovalbumin, lysozyme, and v-globulin on the autoxidation rates of L-ascorbic acid(AsA) in the absence of heavy metal ions and in the presence of Fe(III) or Cu(II) ions in water were examined. AsA was dissolved in a ultra-refined water at a concentration of 50 ${\mu}$M and 5 ${\mu}$M Fe(III) or 0.1 ${\mu}$M Cu(II) were added, and a oxygen gas was bubbled through the solution at a flow rate of 200 ml/min at 35$^{\circ}C$. The amount of remaining AsA in the reaction mixture was determined by using a UV spectrophotometer(at 265 nm). It was found that the Cu(II) at a concentration of 0.1 ${\mu}$M had a more accelerated for the autoxidation of AsA than Fe(III) at 5 ${\mu}$M. Moreover, it was confirmed that the ratio of remaining AsA was significantly larger in the presence of SOD, CAT, BSA, ovalbumin, lysozyme, and v-globulin than in the absence of proteins. The stabilization of AsA by various proteins were confirmed during the autoxidation of AsA in the presence of Fe(III) or Cu(II) in water. It was suggested that the non-enzymatic effects of SOD, CAT and some other proteins might be involves in the stabilization of AsA.

• Food Science of Animal Resources
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• v.25 no.4
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• pp.365-372
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• 2005

This study was carried out to investigate the Physiochemical Properties of loin and rump in the native horse meat from Jeju. In the analysis of chemical composition of loin and rump, the result showed $72.2\%\;and\;73.8\%$ in moisture content $20.1\%\;and\;21.2\%$ in crude protein, $2.42\%\;and\;3.08\%$ in crude Int and $0.13\%\;and\;0.14\%$ in crude ash respectively. Glutamic acid was 3,275mg/100g and 3,577mg/100g in loin and rump each and it had highest result in amino acid analysis. K content was 388.0mg/100g which showed highest result in mineral analysis and next contents were P>Na>Mg>Ca. Oleic acid had highest result in fatty acid composition which were $62.64\%\;and\;63.77\%$ in loin and rump respectively. Cholesterol content of loin and rump were 43.25 and 43.57 mg/100g but showed no significant differences to the part. pH of loin and rump were 5.60 and 5.75 which had no significant differences. Loin had Higher result than that of rump with no significant differences in WHC and springiness of texture analysis. Redness of rump was higher than that of loin. In the sensory evaluation, there were significant differences in the color and odor. Loin had higher result than that of rump in the overall palatability but showed no significant differences. With the result of this experiment native horse meat from Jeju could be understood as good meat resources.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.5
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• pp.709-715
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• 2015

As consumers interest in microgreens is increasing worldwide, the production of leafy microgreens uisng different LED lights was investigated in this study. The experiment was carried out to evaluate the effects of different LED lights on the composition and vitamin C contents of buckwheat microgreens. Physicochemical properties of buckwheat microgreens grown under different lights (red, blue, and white) and control exposed to a dark room were investigated. Moisture contents of buckwheat microgreens were 95.65% under white light (WL), 95.75% under blue light (BL), 90.77% under red light (RL), and 89.71% under dark room (DR). Crude ash contents of buckwheat microgreens grown under WL, DR, RL, and BL were 0.39%, 0.39%, 0.31%, and 0.37%, respectively. Crude protein contents of buckwheat microgreens grown under DR, RL, WL, and BL were 7.12%, 7.81%, 1.60%, and 2.40%, respectively. Crude fat contents of buckwheat microgreens grown under DR, BL, RL, and WL were 1.12%, 0.54%, 0.35%, and 0.22%, respectively. $^{\circ}Brix$ was the highest in microgreens grown under BL and RL and the lowest in buds grown under DR. Vitamin C content was the highest in buds grown under WL and the lowest in buds grown under BL. Total chlorophyll content was the highest in microgreens grown under RL and the lowest in buds grown under WL. For mineral content measurement of buckwheat microgreens, Ca, K, Mg, and P contents were high whereas B, Cu, and Zn contents were not detected. The mineral contents of buckwheat microgreens according to each color of light showed significant differences. These results demonstrated that treatment of different colored LED lights during cultivation was able to increase vitamin C content up to affecting the nutritional value of buckwheat microgreens.

• Korean Journal of Food Science and Technology
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• v.27 no.2
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• pp.151-155
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• 1995

In order to understand some physicochemical and functional properties of whey powders, imported and domestic products were analyzed. The pH values of imported whey powder solution were $5.85{\sim}6.33$, while those of domestic $5.70{\sim}6.43$. The titratable acidity values of imported whey powders were $0.11{\sim}0.18%$, while those of domestic products $0.10{\sim}0.24%$. The contents of moisture, crude ash, protein, lipid and lactose of the imported whey powder were $1.31{\sim}2.10%,\;7.37{\sim}7.49%,\;11.54{\sim}12.14%,\;0.82{\sim}1.40%\;and\;64.43{\sim}72.66%$, respectively, while those of domestic products $2.11{\sim}2.81%,\;5.39{\sim}8.03%,\;10.41{\sim}20.03%,\;1.88{\sim}2.54%\;and\;54.32{\sim}68.42%$, respectively. The active SH group contents of imported whey powders were $0.36{\sim}0.82{\mu}M/g$, while those of domestic products ranged $0.29{\sim}4.83{\mu}M/g$. The protein solubility of imported whey powders were $54.50{\sim}82.26%$, while that of domestic products $26.93{\sim}68.44%$. The emulsifying capacity and the emulsion stability of imported whey powders were $5.83{\sim}12.53cm^{2}/g$ and $10.24{\sim}12.45%$, respectively, while those of domestic products $6.19{\sim}11.28cm^{2}/g$ and $7.28{\sim}9.93%$, respectively. The foam overrun and stability of imported whey powders were $4.34{\sim}5.54%$ and $0.49{\sim}0.66%$, respectively, while those of domestic products $2.56{\sim}4.24%$ and $0.15{\sim}0.35%$, respectively.

• Korean Journal of Plant Resources
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• v.27 no.1
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• pp.60-71
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• 2014

This study was conducted to identify the potential of rape stalk as a raw material for biorefinery process of rape flower. At first, rape stalk (RS) was immersed in distilled water (DW), acetic acid (AA), oxalic acid (OA), sulfuric acid (SA) and sodium hydroxide (SH) solutions, and the content of reducing sugars liberated from immersed RS was analyzed. Glucose, xylose, arabinose and sucrose were detected varying with the immersion type. In particular, 1% AA-immersion of RS for 72 hr was the most effective conditions to liberate glucose from RS. Secondly, the RS residues were used for elementary analysis and fabrication of fuel pellets. In addition to the solution type, concentration of immersion solutions (0%, 1%, 2%) and immersion time (24, 72, 120 hr) were used as experimental factors. The contents of nitrogen, sulfur and chlorine reduced effectively through the immersion of RS in DW, AA and OA solutions. For properties of RS-based pellets, bulk density and higher heating value of RS-based pellets greatly increased with the immersion of RS, and the qualities were much higher than those of the A-grade pellet of the EN standards. Ash content decreased remarkably through the immersion of RS, and was satisfied with the A-grade pellet standard. Durability was negatively affected by the immersion of RS, and did not reached to B-grade of the EN standard. In conclusion, acid immersion of RS can be a pretreatment method for the production of fuel pellet and bioethanol, but use of the immersed RS for the production of high-quality pellets might be restricted due to low durability of immersed-RS pellets. Therefore, further studies, such as investigation of detailed immersion conditions, fabrication of mixed pellets with wooden materials and addition of binders, are needed to resolve the problems.