• Journal of the Korean Wood Science and Technology
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• v.47 no.4
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• pp.519-532
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• 2019

The objectives of this study were to evaluate the effects of shelling ratio and resin content on the properties of bamboo oriented strand board (BOSB) from betung (Dendrocalamus asper) and to determine the correlation between the results of dynamic and static bending tests. Strands were steam-treated at $126^{\circ}C$ for 1 h under 0.14 MPa pressure and followed by washing with 1% NaOH solution. Three-layer BOSB with the core layer perpendicular to the surface was formed with shelling ratios (face:core ratio) of 30:70; 40:60; 50:50; 60:40 and binded with 7% and 8% of phenol formaldehyde (PF) resin with the addition of 1% of wax. The evaluation of physical and mechanical properties of BOSB was conducted in accordance with the JIS A 5908:2003 standard and the results were compared with CSA 0437.0 standard for commercial OSB (Grade O-1). Non-destructive testing was conducted using Metriguard Model 239A Stress Wave Timer which has a wave propagation time from 1 to $9,999{\mu}s$ and a resolution of $1{\mu}s$. BOSB with 8% resin content showed better physical and mechanical properties than those with 7% resin content. The increase of the face layer ratio improved the strength of BOSB in parallel direction to the grain. The results suggested that shelling ratio of 50:50 could be used as a simple way to reduce PF resin requirements from 8% to 7% and to meet the requirements of CSA 0437.0 standard. The results of non-destructive and destructive tests showed a strong correlation, suggesting that non-destructive test can be used to estimate the bending properties of BOSB.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.57 no.3
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• pp.271-279
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• 2012

Total twenty cultivars of potato (Solanum tuberosum L.) were grown at Gangneung where is located in low land of Korea. Their tubers were harvested from 100 to 120 days after planting, and over 150 g of tubers were selected for quality evaluation. Dry matter, starch, amylose in starch, ascorbic acid, protein, individual sugars and mineral were analyzed and mealiness of cooked potatoes were also evaluated by panel test. Dry mater content was the highest in 'Haryeong', 'Jayoung' and 'Shepody', and the biggest starch granules were observed in 'Jayoung' and 'Sinnamjak'. In addition, the content of amylose was highest in 'Haryeong', 'Chudong' and 'Goun'. Mineral content showed the slight difference between cultivars, but it's tendency was not clear. Vitamin C content was highest in 'Jayoung' as 62.5 $mg{\cdot}100g^{-1}$ FW, and 'Chugang' exhibited the highest content of protein. Sugar content was lower in cultivars for single one than double cropping. The lowest sugar content was observed in 'Atlantic' and 'Namseo' among cultivars for single cropping, and in 'Goun' for double cropping. As a result of analysis for quality factors, we could select nine cultivars ('Atlantic', 'Gahwang', 'Gawon', 'Goun', 'Hareong', 'Irish Cobbler', 'Jasim', 'Jayoung' and 'Shepody') with high dry matter content and low reducing sugar as a cultivar group for processing. Additionally, seven cultivars ('Chugang', 'Gawon', 'Goun', 'Hareong', 'Irish Cobbler', 'Jasim' and 'Seohong') with high mealiness and amylose content and five cultivars ('Atlantic', 'Chudong', 'Gahwang', 'Jopung' and 'Jowon') with low mealiness and amylose content were classified as groups for boiled or steam cooking and for soup or pot dishes, respectively.

• Journal of Nutrition and Health
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• v.50 no.6
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• pp.655-663
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• 2017

Purpose: The aim of this study was to analyze the sodium contents of representative Korean foods high in sodium and develop them as a fundamental resource for setting the standard amount of sodium in foods. Methods: A total of 480 representative Korean foods high in sodium were collected from households, foodservice establishments, and restaurants in four regions (Capital region, Chungcheong & Gangwon Province, Gyeongsang province, and Jeolla province) and analyzed their sodium content. Results: The sodium content (per 100 g) of food categorized by food group was highest in kimchi and braised food (p < 0.001), and the sodium content of each food was highest in stir-fried anchovies (1,896.6 mg) followed by braised burdock and lotus roots (820.6 mg) and picked onions (809.3 mg) (p < 0.001). However, the sodium content per portion of food was highest in steamed short ribs (1,429.6 mg) from home meals (p < 0.001), Bibimbap, (1,074.1 mg) and steamed short ribs (838.8 mg) from foodservice (p < 0.001), spicy beef soup (3,273.2 mg), and pollack stew (2,930.2 mg) from restaurants (p < 0.001). The sodium content per 100 g and portion of soups and stews from restaurants was significantly higher than that of home meals and foodservice meals (p < 0.001), and the sodium content per portion of steam dishes and stir-fried dishes from home meals was significantly higher than that of foodservice meals (p < 0.05). Conclusions: These results suggest that developing and using low-sodium soybean sauces & soybean paste and kimchi is needed in an effort to reduce sodium intake. In addition, determination of the sodium contents of representative Korean foods known to be high in sodium is expected to be useful in establishing guidelines for reduction of sodium content.

• Journal of the Korea Organic Resources Recycling Association
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• v.24 no.4
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• pp.105-112
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• 2016

The drying test was carried on the globular type cow manure pellet for use in solid fuel applications. The globular type cow manure pellet fuel was sorted according to size by rotatory sieves. The three kind of drying methods such as convection hot-air drying method, infrared ray drying method and superheated steam method were used to dry the globular type cow manure pellet. Among the three kind of drying methods, superheated steam method of dry time was the shortest. The apparent specific gravity and low calorific value of dried cow manure pelltes was about $250{\sim}350kg/m^3$ and above 3,000 kcal/kg respectively. The smaller the particle size of cow manure pellets, the less drying time was required. The time was required very less for drying smaller particle size cow manure pellet when compared to larger size. In the case of the same drying condition, it has been found that reducing the particle size of cow manure fuel pellet is an important factor for shortening the drying time of the livestock manure pellet.

• Applied Chemistry for Engineering
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• v.29 no.4
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• pp.382-387
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• 2018

In this study, the reaction characteristics of combined steam and carbon dioxide reforming of methane (CSCRM) reaction using Pd-Ni-YSZ catalyst were investigated according to types of catalysts and gas compositions. Catalysts were prepared in the form of powder and porous disk. The injected gases were supplied at different ratios of $CH_4/CO_2/H_2O$. As a result, the conversion of $CH_4$ and $CO_2$ was improved as a result of using the porous disc type catalyst as compared with that of the powder type catalyst. When the $CH_4/CO_2/H_2O$ ratio of the feed gas was 1 : 0.5 : 0.5, the $H_2/CO$ ratio was adjusted close to 2. However, after 6 hours of the reaction, $CH_4$ conversion was partially reduced by the carbon deposition and the pressure drop increased from 0.1 to 0.8. This issue was then solved by optimizing the water content. As a result, it was confirmed that the durability was secured by preventing the carbon deposition when the gas was supplied at a $CH_4/CO_2/H_2O$ ratio of 1 : 0.5 : 1, and the conversion rate was maintained at a relatively high level.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.6
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• pp.795-800
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• 2003

Juniper seed oil extracted by steam distillation has been a useful material as a medicine, insect repellant, and flavorant for alcoholic beverages. As the result of juniper seed oil analysis, the acid value, saponification value, unsaponification value phosphorus contents, and refractive index were 91.04, 85.15, 15.52, 11.04 ppm, 1.47, respectively The content of neutral lipids, glycolipids and phospholipids were 85.4%, 12.2% and 2.4%, respectively. From the fatty acids analysis, the major fatty acids from the juniperseed harvested in August were lauric acid (31.9% ), palmitic acid (28.0% ), stearic acid (9.9%), and oleic acid (8.5%) . However, maturated seed oil harvested in October mainly consists of linoleic acid (47.6%), linolenic acid (17.6%), oleic acid (16.1%), and palmitic acid (11.9%). Upon these analyses, fatty acids composition of juniper seed oil depends on the seed maturation. According to volatile compounds analyses of essential oil extracted using steam distillation method and SPME, the major compounds were $\beta$-myrcene, $\alpha$-pinene, $\beta$-farnescene, $\beta$-cubebene, limonene, trans-caryo-phyllene, $\alpha$-terpinolene, camphene, sabinene, and $\beta$-pinene.

• Food Science and Preservation
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• v.18 no.4
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• pp.552-558
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• 2011

Hypsizigus marmoreus is a wild mushroom commonly consumed in South Korea due to its beneficial effects on health. In the present study, the general chemical and inorganic-element composition, the total amino acid contents, and the volatile-flavor compounds of H. marmoreus were investigated for food uses. The proximate compositions consisted of 60.1% carbohydrate, 32.0% crude protein, 8.98% moisture, 5.0% ash, and 2.0% crude lipid. The minerals in H. marmoreus were found to be as follows; potassium (429.5 mg), phosphorus (101.9 mg), sodium (20.3 mg), magnesium (54.86 mg), calcium (2.7 mg), zinc (0.8 mg), iron (0.7 mg), manganese (0.2 mg), and copper (0.1 mg), based on 100 g of mushroom dry weight. Seventeen kinds of total amino acids were found in H. marmoreus, with the glutamine acid content being the highest (2,340 mg/100 g), followed by the asparagine, serine, arginine, and leucine contents. The volatile-flavor components of H. marmoreus were collected via simultaneous steam distillation extraction (SDE), and were analyzed via gas chromatography-massspectrophotometry (GC-MS). A total of 17 volatile-flavor compounds were identified, including eight aldehydes, seven alcohols, one acids, and one other compounds. The most abundant compound was 2,3,6-trimethy1 pyridine, which accounted for more than 40% of the total volatiles; other important compounds were 1-octen-3-o1, buty1hydroxytoluene (BHT), isoocty1 phthalate, 3-octanal, 1-undecanol, and 2-amylfuran. These results provide preliminary data for the development of H. marmoreus as an edible food material.

• Korean Journal of Food Science and Technology
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• v.46 no.3
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• pp.303-308
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• 2014

This study determined the antioxidant levels and activities of hot water aronia extracts by different drying methods such as sun drying, sun drying after steam treatment, freeze-drying, and oven drying. The total polyphenol content, calculated as gallic acid equivalent, was the highest in the freeze-dried sample (910 mg), followed by sun-dried after steam treatment (779 mg), sun-dried (769 mg), and oven-dried (757 mg) samples. Similar patterns were observed for the total flavonoid and anthocyanin contents. Freeze-dried aronia samples contained the highest polyphenol, flavonoid, and anthocyanin contents as compared to the samples dried by other methods. All antioxidant activities were found to increase in a dose-dependent manner. For the hot water-extracted freeze-dried aronia powder (200 mg/mL), the 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) radicalscavenging activities were 65.5% and 61.7% and the hydroxyl and superoxide anion radical-scavenging activities were 50.5% and 52.1%, respectively. These results suggest that comparatively, freeze-drying is a better method for preserving the bioactive components and the antioxidant activities of aronia.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.4
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• pp.632-638
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• 1997

To develop the Instant Nuroong-gi in a short reconstitution time, we made puffed Instant Nuroong-gi samples and investigated their physicochemical characteristics. The Nuroong-gi was prepared using a Japonica variety with three different cooking conditions: steam cooker(process A), pressure cooker (process B) and cabinet cooker(process C). The Instant Nuroong-gi is produced by adding water to the Nuroong-gi which is broken into the size of 0.5~1.0cm. The amount of the added water is 40% of the weight of the broken Nuroong-gi. And it was puffed at 160~17$0^{\circ}C$ for 30 secands. The water binding capacity of Instant Nuroong-gi samples was 7.2 at process A, 6.5 at process B and 6.6 at process C. The total sugar content of Instant Nuroong-gi samples in hot water reached at the highest level at 3-minute cooking time. Through the sensory evaluation by a panelists, we discovered that Instant Nuroong-gi prepared by a steam cooker showed the highest roasted nutty taste, hardness, stickiness and overall acceptability. And Instant Nuroong-gi prepared by a pressure cooker showed the highest color, clearness, and roasted nutty flavor. Correlation coefficients between overall acceptability and other sensory attributes of Instant Nuroong-gi indicated that hardness had the most significant correlation to sensory evaluations. When we compared the results of color test with those of sensory evaluation of Instant Nuroong-gi prepared by three different cookers, we discovered that panelists preferred yellow Instant Nuroong-gi prepared by a pressure cooker. We found some morphological properties of Instant Nuroong-gi as a result of the comparison of the crystalization by a X-ray diffraction analysis and the observation of the shapes by a the scanning electron micrographs.

• Resources Recycling
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• v.31 no.5
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• pp.42-51
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• 2022

Aggregate resources in Korea are expected to run out owing to an increase in development demand and construction investment. Recycled concrete aggregates (RCA), extracted from waste concrete, have a lower quality than natural aggregates. However, RCA can produce concrete similar in quality to the normal concrete by aggregate pretreatment, use of admixtures, and quality control. RCA are most suitable for use in precast concrete products such as sidewalk blocks and revetment blocks. Herein, the feasibility of producing revetment blocks using recycled aggregate concrete (RAC), similar in quality to normal concrete, was analyzed. The amount of RCA was varied, and moderate high early strength cement and steam curing were used to produce the concrete test blocks. In the block test, the load resistance characteristics of the blocks were evaluated to determine optimal RAC and glass fiber reinforced polymer (GFRP) rebar compositions. Thus, the variable that reduced the cement content was determined at the same level as that of natural aggregate concrete by the control of steam curing. In the concrete block test, although this depends on the reinforcement ratio, the RAC block exhibited the same or better performance than a normal concrete block. Therefore, the low quality of RCA in RAC is no longer a problem when concrete mixing and curing are controlled and appropriate reinforcement is used.