• Journal of Mushroom
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• v.1 no.1
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• pp.1-8
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• 2003

Mushroom cultivation in Korea was launched in the early 1960's. At that time Korean government started a program for increasing cultivation of button mushroom (Agaricus bisporus) and oak mushroom (Lentinula edodes) to export agricultural products and to increase farm income. National research institutes under Rural Development Administration, Korea Forest Service, etc. play a leading role in mushroom industry as follows : Development and spread of genetically superior commercial strains, good spawns, and cultivation techniques. Training and field advice to lead farmers for mass production of high quality mushrooms. Political support of facilities and establishments for mushroom cultivation. Several mushrooms including oak mushroom, button mushroom, oyster mushroom, winter mushroom, Ganoderma, P. eryngii, etc. have been popularized for their cultivation techniques and produced in large quantities in the farm. According to a recent statistics, mushrooms have been grown by about 20,000 farm households, in Korea and the gross production of fresh mushrooms is estimated about 170,000 M/T. The gross production of oyster mushroom is the highest followed by winter mushroom, oak mushroom and button mushroom. The gross amount of mushroom production stands over 700 billion won. Thus, mushroom industry goes to the most important cash crop to be produced yearly.

• Asian-Australasian Journal of Animal Sciences
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• v.24 no.10
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• pp.1464-1472
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• 2011

Effects of a supplemental fermented agro by-products diet on growth performance, blood characteristics and carcass traits were investigated in fattening pigs. The fermented diet mainly contained 38.0% brewer's grain, 25.0% rice bran and 21.0% byproduct of king oyster mushrooms. The mixed ingredients were fermented at $40^{\circ}C$ for 7 days and fed to crossbred barrow pigs for 62 days. Ninety pigs were housed in 10 head per pen with three replicate pens per treatment. The pigs in the control group were fed with formula feed, while the pigs in T1 group were fed 20, 40, 60, 80 and 100% fermented diet substituted with formula feed on 1 week interval. Pigs in T2 group were fed 30, 60 and 100% fermented diet substituted with formula feed on 1 week interval. The fermented diet significantly (p<0.05) decreased body weight gain and feed efficiency of pigs. The blood characteristics differed with diet types. Carcass grade was significantly better (p<0.05) in the pigs fed fermented diet than in the pigs fed control diet as well as ratio of high grade was higher in the fermented diet groups. Therefore, although a dietary of fermented diet decreased growth performance and feed efficiency, it improved the carcass grade in pigs.

• Economic and Environmental Geology
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• v.52 no.3
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• pp.223-230
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• 2019

The calcination of oyster shells have been studied as the possible substitute for the limestone used as an absorbent of $SO_2$ gas. However, since pure shells can not be used in calcination process, some impurities are contained and the changes in the characteristics of the calcination products are expected. In this study, the surface characteristics of the calcination products are investigated by mineralogical analysis according to the contents of NaCl, which can be derived from sea water, and sediments on the surface of the shell as impurities. The marine sediments on the shells were mainly composed of quartz, albite, calcite, small amounts of amphibole and clay minerals such as ilite, chlorite and smectite. After calcination of oyster shells mixed with 0.2-4.0 wt% sediments at $900^{\circ}C$ for 2 hours, regardless of the dehydration, dehydroxylation, and phase change of these minerals at the lower temperature than this experiment, no noticeable changes were observed on the specific surface area of the calcined product. However, when mixed with 0.1 to 2.0 wt% NaCl, the specific surface area generally increases as compared with the shell sample before calcination. The specific surface area increases with increasing amount of salt, and then decreases again. This is closely related to the changes of surface morphology. As the amount of NaCl increases, the morphology of the surface is similar to that of gel. It changes into a slightly angular, smaller particle and again looks like gel with increasing amount of NaCl. Our results show that NaCl affects morphological changes probably caused by melting of some oyster shells, but may have different effects on the specific surface area of calcination product depending on the NaCl contents.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.50 no.5
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• pp.494-499
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• 2017

This study evaluated the abundance of fecal coliforms in oysters Crassostrea gigas, sea squirts Halocynthia roretzi and sea cucumbers Apostichopus japonicus in fisheries along the coast of Korea in 2014, and investigated the prevalence of antimicrobial resistance in Escherichia coli isolated from these fishery products. The ranges of fecal coliforms found in oysters, sea squirts and sea cucumbers were <18-20, <18-330 and <18-3,300 MPN (most probable number)/100 g, respectively. Sea squirts contained the greatest range of E. coli (<20-140 MPN/100 g), followed by sea cucumbers (<20-130 MPN/100 g) and oysters (<20-20 MPN/100 g). A total of 26 strains of E. coli were isolated from 34 sea squirt, 25 sea cucumber and 13 oyster samples. Strains thus isolated were tested for their susceptibility to 22 antimicrobial agents used in Korea for medical or veterinary therapy. E. coli isolates showed the greatest resistance to ampicillin (84.6%), followed by trimethoprim (34.6%), nalidixic acid (34.6%), tetracycline (30.8%), pipemidic acid (26.9%), streptomycin (23.1%), chloramphenicol (23.1%), trimethoprim/sulfamethoxazole (23.1%), and gentamicin (15.4%). Resistance to at least one antimicrobial agent was present in 88.5% of E. coli isolates. Of the 26 isolated, six strains (23.1%) were resistant to multiple antimicrobial agents.

• Korean Journal of Food Science and Technology
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• v.20 no.3
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• pp.363-370
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• 1988

An attempt was made in this study to investigate the possibility of processing oyster and sea mussel into an intermediate moisture food. To obtain a palatable and instant product, shucked samples were heated in soy sauce for 5 min., heated in seasoning solution for 10 min., and then dried by the method of hot-air blowing for 4-6 hours at $40^{\circ}C$. Optimum seasoning solutions consisted of 2% monosodium glutamate, 3.5% sodium chloride, 15% sorbitol, 2% propylene glycol, 5% glycine and 0.02% rosemary oleoresin in 72.48% water. Judging from water activity, thiobarbituric acid, viable cell count, volatile basic nitrogen, surface color and sensory evaluation, vacuum-packaging method in nylon/PE $(20{\mu}m/40{\mu}m)$ or polyester/viniliden chloride/polypropylene $(12{\mu}m/15{\mu}m/50{\mu}m)$ film bag did hardly damage to the quality of intermediate moisture products, but air-packaging method in polyethylene(0.06m/m) bag did considerable damage to the quality during storage for 60 days in an incubator with 49-51% relative humidity at $30^{\circ}C$.

• Journal of the Korean Ceramic Society
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• v.44 no.9
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• pp.517-523
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• 2007

For the preparation of tricalciumaluminate $(C_3A)$ clinker, in traditional clinkering method using oxides and carbonates as a raw material, uneconomical repetition of burning have been necessary to avoid the melting of clinker by eutectic reaction in the system $CaO-Al_2O_3$. In this study, special starting raw materials for the clinker burning were prepared from a mixture of oyster shell and aluminium hydroxide by heating to $1100^{\circ}C$ and hydrating at $30^{\circ}C$. The starting raw materials, hardened body with weak hydraulic strength, were mainly composed of $C_3AH_6$ formed by resolution-precipitation mechanism of the system $CaO-Al_2O_3-H_2O$. By heating them, relatively pure $C_3A$ clinker could be obtained by one-time burning at the fairly lower temperature than that of conventional method. The easier formation of $C_3A$ clinker seemed to be caused by higher compositional homogeneity and stoichiometry of the starting materials, high surface area and crystallographic instability of the thermally decomposed products, and the catalytic effect of decomposed moisture on the early-stage crystallization of calciumaluminates. The basic hydration behavior of the clinker was also confirmed.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.34 no.4
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• pp.389-393
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• 2001

For an effective utilization, quality stability of instant powdered oyster soup made of canned oyster processing waste water (IPSW) was determined. Instant powdered soup from oyster hot-water extracts (IPSE) was also prepared by mixing hot-water extract powder (15 g) with table salt (5 g), cream powder (19 g), milk replacer (12 g), wheat flour (20 g), corn flour (15 g), starch (5 g), glucose (7.5 g) and onion powder (1.5 g). In preparing IPSW, mixed powder from wash water and boiling liquid waste, instead of powder from hot-water extracts and table salt, was added (powder from boiling liquid waste: powder from wash water= 12: 8) and other additives were added in proportion to those in the IPSE. The moisture content, water activity, peroxide value and fatty acid composition showed little changes during storage of the IPSW. The pH, volatile basic nitrogen content and brown pigment formation increased slightly, while white index decreased slightly during storage of IPSW. No significant difference was observed in the changes of food component during storage between IPSW and IPSE. According to a sensory evaluation, the change in quality of IPSW was negligible during 12 months of storage. from the results of the chemical experiment and sensory evaluation, IPSW packed with laminated film bag (OPP, $20{\mu}m/PE,\;20{\mu}m/paper,\;45g/m^3/PE,\;20{\mu}\;m/Al,\;7{\mu}\;m/PE,\;20{\mu}m$) was revealed to be preserved in good quality during 12 months of storage.

• Journal of Mushroom
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• v.17 no.4
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• pp.205-210
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• 2019

This study was conducted to elucidate the optimal nitrogen content for each variety of oyster mushroom (Pleurotus ostreatus) by investigating the change in the characteristics of fruiting body according to the nitrogen content of the sawdust media, and to use the results as the basic data for cultivation of high quality oyster mushroom. The nitrogen content was adjusted to 1.3%, 1.6%, 1.8% and 2.3%, and at each condition, mycelial growth was observed, which showed that the nitrogen content did not affect the rate of mycelial growth and density substantially. In the investigation of the characteristics of fruiting body, at the 1.8% nitrogen content, Chunchu No.2 showed the pileus diameter of 27 mm, and the stipe diameter and length of 11 mm and 61 mm, respectively, and the measurement of its color values revealed that the brightness of the pileus and the stipe was 31 and 80, respectively, offering the best commercial value, and yielding 25 valid stipes, which was the largest number. Likewise, at the 1.8% nitrogen content, Heuktari also showed the excellent growth characteristics including the pileus diameter of 29 mm and the stipe diameter and length of 10 mm and 68 mm, respectively, and the superb color values of the brightness of 37 at the pileus and 78 at the stipe. Moreover, the number of valid stipes was also found to be the highest with 19. In terms of morphological characteristics such as the pileus diameter and color, Soltari also produced the best mushrooms at the 1.8% nitrogen content and the number of valid stipes was high with 22. In summary, irrespective of varieties of oyster mushroom, high quality products could be cultivated at the nitrogen content of 1.8%.

• Journal of Korean Society on Water Environment
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• v.32 no.2
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• pp.216-221
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• 2016

The adsorption characteristics of mixed heavy metals (Cr(III), As(VI)) in aqueous solution were investigated using a sediment amendment composite. Sediment amendment composite was composed of clean sediment (40%), zeolite (20%), recycled aggregate (10%), steel slag (10%), oyster shell (10%), and cement (10%). The experimental results showed that the adsorption equilibrium was attained after 180 mins. Heavy metal adsorption was characterized using Freundlich and Langmuir equations. The equilibrium adsorption data for the sediment amendment composite better fitted with the Langmuir model than the Freundlich model. The maximum adsorption capacity of Cr(VI) (36.07 mg/g) was higher than As(III) (25.54 mg/g); and the adsorption efficiency of the Cr(VI) and As(III) ions solution decreased with decreasing pH from 2 to 10. The collective results suggested that the sediment amendment composite is a promising material for a reactive cap that controls the release of Cr(VI) and As(III) from contaminated sediments.

• Journal of the Korean Society of Food Science and Nutrition
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• v.18 no.2
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• pp.211-215
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• 1989

The fatty acid composition of lipids separated from 14 kinds of canned fish and shellfish products from the market were examined. The crude lipid contents of canned fish and shellfish products showed wide difference (1.3-15.2%) depending on raw materials and kinds of products. Fatty acid composition of products were mainly consisted of polyenoic acid(34.5-61.4%), and followed by saturated acid(24.5-47.8%), monoenoic acid(12.4-32.0%). The major fatty acids were palmitic acid, palmitoleic acid oleic acid, eicosapentaenoic acid and docosahexaenoic acid. In case of canned tuna in oil and canned smoked oyster in oil, linoleic acid was the most predominant component(48.2%, 34.6%). Judging from the results, canned fish and shellfish products were abundant of the polyunsaturated fatty acids in spite of the high temperature sterilization and lone storage periods.