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        검색결과 4,701

        3882.
        2017.06 KCI 등재 서비스 종료(열람 제한)
        Biomass adsorbents were prepared from fallen oak leaves. In the activation process for fallen oak leaves, various operating parameters such as the activation temperature (600-900°C), steam injection rate (5-15 cc/hr), and steam injection time (1- 3 hr) were adopted. For analyses of the manufactured adsorbent, various methods such as scanning electron microscope (SEM), measurements of the BET surface area and chemical composition analyses were adopted. Regarding major adsorption characteristics, the adsorption equilibrium capacity was measured using batch type experimental apparatus for various biomass adsorbents. The experimental result showed that the H2S adsorption equilibrium capacity of the adsorbent made from fallen oak leaves decreased as the activation temperature and steam injection rate increased for a given range.
        3883.
        2017.05 서비스 종료(열람 제한)
        Background : Currently, obesity and adult diseases as a result of sugar intake have been a consistent problem in Korea. Natural sweeteners as sugar substitutes have many advantages over sugar as a small quantity. Therefore, this study was conducted to investigate possibility of industrialization as food additives by using the nature sweetness components of stevia (Stevia rebaudiana Bertoni). Method and Results : Stevia was cultivated in a plastic house. The leaves and stems were harvested at October. They were ground into fine powder using a mill, and were extracted by high temperature and pression extraction method. The extracts were evaporated under vacuum and lyophilized. Three strawberry cultivars of ‘Seolhyang’, ‘Maehyang’, and ‘F22-196’ were cultivated in a plastic house and were harvested from March to May. The fruits harvested were stored at 50℃ until processing. In order to test the processing suitability of stevia extract, the characteristics of the three strawberry varieties (line) were investigated. As a result, the ‘F22-196’ line, which was bred as a processing strawberry, generally contained more antioxidant materials and activity than those of ‘Maehyang’ and ‘Seolhyang’ varieties. Comparing the sugar contents which affects the quality of strawberry jam, the average sugar contents of ‘F22-196’ line was higher than 'Maehyang' and 'Seolhyang' varieties. In the preparation of strawberry jam using ‘F22-196’, strawberry jam was prepared by adding only sugar or stevia extract powder, which was 1/100 of the amount of the sugar in only sugar strawberry jam, to the sensory test. As a result, we identified that sugar jam and stevia jam added stevia extract showed 50 : 50 at the sensory test and stevia jam does not make a difference to the marketing jam at the point of view of general consumers. Conclusion : ‘F22-196’ line represented the best quality for strawberry jam in test caltivars. Stevia powder is judged to be used as a sweetener of sugar substitutes in the production of strawberry jam and processing food.
        3884.
        2017.05 서비스 종료(열람 제한)
        Background : Platycodon grandiflorum root (PGR) was one of the primary herbs used in a phlegm-relieving herb from the past. Platycoside compounds on PGR may exhibit neuroprotective, antimicrobial, anti-inflammatory, anti-cancer, anti-allergy, improved insulin resistance, and cholesterol-lowering properties. In order to developing a concentrate product that improved the functionality and preference of PGR, it was fermented using lactic acid bacteria (Lactobacillus plantarum N76-10 and 56-12). Methods and Results : The concentrate products were created by PGR-concentrate (PGRC, 60 ºBrix) mixed with fermented PGR-extract (FPGRE, 2 ºBrix) at the level of 0, 50, 100, 150 and 200%. Sweetness and preference were supplemented by other added materials including honey, oligosaccharide, concentrate of jujube (60 ºBrix) and pear (60 ºBrix), and cactus Chounnyouncho extract (2 ºBrix). The products were put into investigation for their preference of taste, antimicrobial activity in accordance with amount of FPGRE. When it comes to preference of taste, the most favor is adding 100% of FPGRE on PGRC. The product added 150% FPGRE exhibited a strong microbial anti-proliferation in all four kinds (Corynrbacterium diphtheriae, Klebsiella pnneumoniae, Staphylococcus aureus, and Streptococcus pyogenes) of bacteria inducing bronchus diseases and was higher antimicrobial activity than concentrate without FPGRE. In terms of the sensory evaluation (taste, texture and visco-elasticity), concentrate mixed with FPGRE (10), jujube concentrate (2), pear concentrate (10), cactus Chounnyouncho extract (10), oligosaccharide (2), honey (1) and xanthan gum (0.02) showed the highest scores. Conclusion : Thus, A PGR concentrate was made by adding FPGRE (100%) and it was increased organoleptic quality, antimicrobial activity. These studies may provide new product development for effective utilization on Platycodon grandiflorum root.
        3885.
        2017.05 서비스 종료(열람 제한)
        산업장에서 사용되는 산업용 세척제는 대부분 합성계면활성제를 사용하기 때문에 사람에게 장기간 노출될 경우 피부 갑작자극 면역기 저하를 통해서 비염, 천식, 아토피 등을 유발할 수 있으며, 기계에는 부식성에 의해 기계의 이상을 가져올 수 있다. 가정이나 제조업체에서 대량으로 방출되는 폐식용유를 이용하여 산업용 세척제를 만들 경우 폐자원의 재활용과 수계유입시 발생하는 환경오염을 차단할 수 있다. 또한, 폐식용유는 식물성유지가 대부분의 성분으로 유해화학물질이 거의 없으며 pH가 약알칼리성이기 때문에 산업용 계면활성제로 제조할 경우 인체에 무해하고 기계에 대한 부식성도 없는 특징을 가질 수 있다. 따라서, 본 연구의 목적은 산업용 세척제의 재료로 폐식용유를 사용하여 에스테르의 가수 분해에 의해 카르복실산과 알코올을 생성하는 비누화 반응을 촉진하고 유용성 미생물과 발효기술 등을 접목하여 산업용 세척제를 개발하는 것이다. 이렇게 개발된 세척제는 평가 항목으로 표면장력, pH, 수분 및 휘발성 물질, 메틸알콜, 형광증백제, 석유 에테르 가용성분, 생분해성, TOC, 중금속(As, Pb 등), 부식성 등에 대한 성능을 분석 및 평가하고 생산된 시제품을 산업현장에서 사용하여 제품의 현장 적용성을 확인함으로써 성능의 우수성과 단점을 보완하여 제품에 반영하고자 하였다.
        3886.
        2017.05 서비스 종료(열람 제한)
        산업의 발전과 경제규모의 팽창에 따라 에너지소비가 크게 증가되는 가운데 대기오염물질배출이 크게 늘어나면서 심각한 환경문제를 야기하고 있다. 이중에서 황화수소(H2S)는 계란 썩는 냄새가 나는 무색의 유독한 기체로서 인체의 위장이나 폐에 흡수되어 질식, 폐 질환, 신경중추마비 등을 발생시키고 있다. H2S 가스는 폐기물 매립장, 석유 정제업, 펄프공업, 도시가스 제조업, 암모니아공업, 하수처리장 등 다양한 곳에서 발생하고 있으며, 이를 처리하기 위하여 심냉법, 흡수법, 막분리법, 흡착법 등 여러 가지 처리방법이 제시되었다. 본 연구에서는 실험실규모의 장치를 이용하여 바이오매스 부산물을 활용한 악취저감용 흡착소재개발을 위해 밤껍질을 대상으로 탄화, 스팀활성처리등의 과정을 거쳐 흡착제를 제조하였으며, BET분석, SEM등을 이용한 물성분석, 회분식의 흡착평형실험, 악취 모니터링실험을 통한 흡착특성을 고찰하였다. 실험결과, 밤껍질을 활용하여 탄화 및 활성처리과정을 거치면서 얻을 수 있는 흡착제의 수율은 15∼20%에 해당되는 것으로 밝혀졌다. 또한, 밤껍질부산물은 스팀을 이용한 활성처리 과정에서 온도가 증가할수록. 시간이 증가할수록 스팀-탄소 화학반응에 의해 내부기공이 커지면서 비표면적이 증가되는 것으로 밝혀졌다. 아울러, 밤껍질부산물을 소재로한 흡착제의 황화수소 평형흡착능과 파과성능은 활성탄대비 비교적 우수한 성능을 보임으로써, 악취제거용 흡착소재로 활용성이 클 것으로 예상되었다.
        3887.
        2017.05 서비스 종료(열람 제한)
        식품제조업에서 발생하는 동식물성잔재물은 발생량이 많고 성상이 균질하여 재활용에 유리하다. 동 폐기물을 재활용할 때 경제성이 있는 것은 배출업체와 재활용업체가 협력하여 재활용이 효율적으로 이루어지고 있으나 발생량이 적고, 영양성분의 함량이 높지 않은 업체의 폐기물은 경제성이 낮아 원활히 재활용되지 못하고 있다. 폐기물배출업체는 재활용에 따른 환경보전 효과보다는 처리비용 절감을 중요시하기 때문에 사료원료로 쓰일 수 있는 것이 퇴비원료로 사용되거나 퇴비원료로 사용할 수 있는 것이 소각이나 해역배출 등으로 처리되고 있는 실정이다. 따라서 식품제조업에서 발생하는 동・식물성잔재물의 배출과 재활용 및 처리실태, 유통 현황을 파악하고 재활용 활성화 대책을 마련하는 것이 필요하다. 본 연구에서는 식품제조업체 중 다량 발생하는 업종인 동식물성유지제조업과 전분 및 당류제조업을 선정하여 대상 업종에서 발생하는 폐기물(부산물)의 발생원단위를 파악하였고, 이를 통해 대상 업종별 물질흐름도(Material Flow Analysis) 작성을 통해 국내 전체의 물질흐름을 추정하였다. 또한 해당업종에서 발생하는 동식물성잔재물을 재활용함으로써 현재 사료용으로 수입되고 있는 품목에 대한 수입대체효과를 산출하였고, 일선 현장에서의 폐기물의 발생, 처리, 재활용 실태를 조사하였다. 조사결과를 통해 동식물성잔재물의 세부 분류번호를 보완하는 방안과 재활용 가능한 동식물성잔재물의 재활용 가능 유형을 실제 재활용형태를 고려하여 개선하는 방안을 제시하였다. 동 폐기물의 재활용을 활성화하기 위해서는 외국의 식품폐기물 발생억제와 재활용 정책의 추진성과를 참고하여 식품의 제조, 유통과정에서 발생하는 식품폐기물 재활용 대책을 마련할 필요가 있으며, 일본에서 시행하고 있는 재생이용사업계획(리사이클루프) 인정제도의 국내 도입과 향후 수요처 감소로 재활용이 원활하게 이루어지지 않을 가능성이 있는 오리가공부산물의 재활용, 그리고 현재 폐기물로 관리되고 있는 깨박의 순환자원인정에 대하여 검토하였다. 본 연구 결과는 국내 식품제조업에서 발생하는 동식물성잔재물의 통계작성과 해당 폐기물의 재활용 정책을 추진하기 위한 기초 데이터로 활용될 수 있을 것으로 판단된다.
        3888.
        2017.04 KCI 등재 서비스 종료(열람 제한)
        Powder mine wastes cause secondary environmental problems from dust flying around villages. It is necessary to recycle to prevent this secondary pollution and to use its beneficial contents. Magnesium and iron may play a role like that of aluminum in geopolymer forming. In this study, therefore, we analyzed the compressive strength of geopolymer prepared from melting slag (MS) and high-magnesium iron mine waste (MW). The compressive strength increased by increasing the mixing ratio of MS and decreasing the L/S ratio. The optimal properties were obtained at a mixing ratio of MS to MW of 5 : 5, molar ratio of SiO2/Na2O of 1.8, and L/S ratio of 0.2. Under these conditions, the compressive strength at 28 days was 112.5 MPa. According to the FT-IR analysis, a geopolymer structure was identified. As a result, we confirmed the possibility of geopolymer forming from MS and MW.
        3889.
        2017.04 KCI 등재 SCOPUS 서비스 종료(열람 제한)
        본 연구에서는 호박고구마의 산업적 이용 증대 및 식품가공용 소재 개발을 목적으로 분무건조공정을 이용하여 호박고구마 효소 분해물을 분무건조한 다음 물리화학적 특성 및 소화특성을 조사하였다. 호박고구마 효소 분해물의 불용성 식이섬유, 수용성 식이섬유 및 총 식이섬유 함량은 4.17%, 2.07% 및 6.24% 이었다. 호박고구마 효소 분해물의 분무건조분말 제조는 펙틴을 피복물질로 사용하여 분무건조하였으며, 수분함량 및 전분함량은 1.68-2.46 및 45.32-46.51%였다. 색도는 분무건조 분말에서 L 값 및 a 값은 감소하고 b 값은 증가하는 경향을 나타내었다. 입자크기는 분무건조 분말이 37.17-42.32 μm을 나타내어 동결건조 분말 247.79 μm에 비하여 유의적으로 작은 크기를 나타내었으며, 입자모양은 전반적으로 구형의 형태에 펙틴 첨가량이 증가할수록 굴곡이 증가하였다. 수분흡수지수는 분무건조 분말에서 1.74-1.91로 동결건조 분말 2.15에 비해 낮은 수분흡수지수를 나타내었으며, 수분용해지수는 분무건조 분말에서 80.75-87.61%로 동결건조 분말(70.47%)보다 높게 나타났다. 장 상피세포 부착능은 분무건조 분말에서 2.66-6.18%를 나타내어 동결건조 분말 1.79%에 비해 높은 부착능을 나타내 장 내 유용 미생물의 증식을 촉진함을 확인하였다. 분무건조 분말의 인체 내 소화 모델에서, 펙틴 1% 첨가 분말은 최종적으로 장액에서 70.09%의 소화율을 나타내어 동결건조 분말 24.23%에 비해 인체내에서의 높은 소화율이 기대되었다. 따라서 분무건조 분말 제조시 식품산업 활용 측면에서 가공적성이 향상되고 in vitro 인체 내 소화모델에서 소화가 개선된 식품가공용 소재 개발에 있어 산업적으로 적용 가능할 것으로 사료된다.
        3891.
        2017.03 KCI 등재 서비스 종료(열람 제한)
        In this study, we investigated variations in particle size distribution in the process flow from a fluff-SRF manufacturing process in Y city via particle size analysis of waste. About 110 kg of MSW was analyzed in accordance with the process flows for the analysis of the particle size distribution by separating from 300 mm to 10 mm. The first tranche of waste was crushed with a primary crusher such that 100% of particles were smaller than 200 mm. A secondary crusher was used to ensure that 90% of particles were smaller than 10 mm. The crushing function and disintegration effect resulted in waste that contained 30% particles smaller than 10 mm. The primary multistage bulk selection process separated the first non-combustibles from waste passed by the secondary crusher. It produced 19.24% non-combustibles. Secondary multistage bulk selection discharges the final set of non-combustibles from the first non-combustibles after recovering any remaining combustibles. The combustible recovery ratio was 28.24%, and the final non-combustible discharge ratio was about 71.76%. The regular and high-speed disintegrators exhibited 85% and 97% efficiency in producing waste smaller than then 50 mm, respectively. This is thought to improve the yield and quality of SRF in the context of a reasonable management plan via characteristic analysis of residues from the disintegration process.
        3892.
        2017.03 KCI 등재 서비스 종료(열람 제한)
        Ethyl (4-(2,3-dihydro- 1H-indene-5-carboxyamido) benzoate)는 노화방지 효과가 있으나 난 용성 및 결정화 특성을 가지고 있어 제형화 및 2차 가공을 통해 입자내 활성성분을 담지시키는데 어려움이 있으 며, 3,5,7-trihydroxy-4’-methoxy-8-prenylflavone는 플라보노이드(flavonoid)류의 일종으로 미백기능 을 가지고 있으나 복합제형에 사용할 경우 제형의 착색을 일으키는 물질 중 하나이다. 본 연구에서는 전기방사법 을 이용하여 유용성/난용성 생리활성성분인 ethyl (4-(2,3-dihydro-1H-indene-5-carboxyamido) benzoate) 와 3,5,7-trihydroxy-4’-methoxy-8-prenylflavone 성분을 각각 poly (methyl methacrylate)와 polycaprolactone 고분자 입자 내에 담지 시키고 이를 화장품 제형에 적용했을 때 나타나는 효과에 대해서 기술 하였다. 입자내 활성성분을 담지시킨 고분자 입자를 제조하는 과정에는 고분자의 농도, 노즐의 구조, 그리고 고 분자와 생리활성 성분의 상용성이 중요한 역할을 하였다. 아울러 3,5,7-trihydroxy-4’-methoxy-8-prenylflavone가 캡슐화된 polycaprolactone 고분자 입자를 금속산화물이 포함된 화장품 제형과 혼합하였을 경우, 고분자 입자는 캡슐화 되지 않은 flavonoid가 제형에 포함되었을 경우 나타나는 착색현상을 방지하는 데 효과적 일 수 있다는 결과를 확인하였다.
        3893.
        2017.02 KCI 등재 SCOPUS 서비스 종료(열람 제한)
        본 연구에서는 전통 재래식 콩된장의 제조공정을 과학적으로 해석하기 위한 연구의 일환으로 생메주의 건조 및 발효과정에 있어서 수분함량과 단백질 분해에 의한 아미노산 생성과정을 근적외 분광법으로 쉽게 판단 할 수 있는지 그 가능성을 조사하였다. 생메주를 일정한 크기(3×4×3 cm)로 잘라서 수분이 30%가 되도록 25℃ 항온기에 3주간 발효시킨 모델계 발효메주를 만들어 가시광-근적외 스펙트럼을 측정하여 해석하였다. 발효가 진행됨에 따라 수분이 감소되면서 수분과 관련이 있는 1,430 nm대의 흡광도가 감소 및 시프트 되는 것이 관찰되었고, 발효기간이 길어질수록 아미노산과 관련이 있는 2,050 nm대의 흡광도가 증가하는 것을 관찰 할 수 있었다. 전통 재래식 발효메주를 속부분과 겉부분으로 분리하여 1,000-2,250 nm에서의 가시광 스펙트럼과 근적외 스펙트럼 데이터로 판별분석한 결과, 겉부분과 속부분이 잘 판별되었고, 가시광 보다는 근적외 영역에서 잘 구분되었다. 이들 전통메주중의 아미노산 농도를 비파괴 측정하기 위해 PLSR한 결과 R²은 0.9 이상이며, RMSECv 0.23%로 나타났으며, 전통메주중의 수분함량도 R² 0.81, RMSECv 0.83%이어서 근적외 분광법으로 전통메주의 품질을 비파괴 측정 가능할 것으로 판단되었다.
        3894.
        2017.01 KCI 등재 서비스 종료(열람 제한)
        This paper was evaluated manufacturing properties for core material of self-healing capsules using cement powder, it was found that coagulants for coagulation of core materials were important factors in manufacturing core materials.
        3895.
        2017.01 KCI 등재 서비스 종료(열람 제한)
        Solid refuse fuel (SRF), which is made of combustible waste, has to pass the government’s rigid standards. The Korean government plans to enhance the ratio of biomass energy to total energy use from 3.17% in 2013 to 4.16% in 2020. In particular, the Korean government aims to raise the ratio of combustible waste converted into SRF from 16% in 2014 to 100% in 2020 by increasing the number of facilities manufacturing and utilizing SRF. We attempt to analyze the external benefits of the expansion using the data obtained from a survey of 1,000 randomly selected households. A choice experiment, an economic technique, is employed here. The attributes considered in the study are ‘improvement of energy security’, ‘reduction of greenhouse gases emissions’, ‘extension of landfill life expectancy’, ‘job creation’, and ‘price’ measured as an additional amount of monthly electricity and heating bills per household. The multinomial logit model, which requires the assumption of the ‘independence of irrelevant alternatives’, is applied. However, the assumption could not be satisfied in our data. Thus, we finally utilized a nested logit model that does not require the assumption. All the parameter estimates, except for ‘improvement of energy security’, in the utility function are statistically significant at the 5% level. The estimation results show that the marginal willingness to pay (MWTP) for one year increase in landfill life expectancy is estimated to be 218.8 won per household per year. MWTP for 100,000 tCO2 decrease in greenhouse gases emission is calculated to be 171.9 won per household per year. MWTP for the creation of a new job is computed to be 10.7 won per household per year.
        3896.
        2017.01 KCI 등재 서비스 종료(열람 제한)
        Multi-Walled Carbon Nanotubes (MWCNTs) were modified with epoxy and aminosilane diethanolamine (DEA), and nanocomposites of poly(butylene adipate-co-terephthalate) (PBAT) and the modified MWCNTs were prepared with the aim of improving the physical properties of biodegradable PBAT. The physical and the thermal properties of the PBAT/MWCNT nanocomposites were investigated using various techniques. Fourier transform infrared spectroscopy measurements revealed that the MWCNTs were efficiently modified with DEA. Scanning electron micrographs of the nanocomposites indicated that the modified MWCNTs were dispersed homogeneously in PBAT. The thermal stability of the nanocomposite decreased with increase in the content of epoxy-MWCNT-DEA due to the poor thermal stabilities of epoxy and amino silane DEA. However, the surface hydrophobicity of the nanocomposite increased. The highest stress (170% of PBAT) was observed when the content of epoxy-MWCNT-DEA in the nanocomposite was 2 wt%.
        3897.
        2016.12 KCI 등재 서비스 종료(열람 제한)
        Zeolite (FZ) prepared using coal fly ash from an Ulsan industrial complex was immobilized with polysulfone (PS) to fabricate PS-FZ beads. The prepared PS-FZ beads were characterized by scanning electron microscopy and Fourier transform infrared spectroscopy. The optimum ratio for preparing PS-FZ beads was 1 g of PS to 2 g of FZ. The removal efficiencies of Sr and Cu ions by the PS-FZ beads increased as the solution pH increased and nearly reached a plateau at pH 4. A pseudo-second-order model morel fit the adsorption kinetics of both ions by the PS-FZ beads better than a pseudo-first-order model. The Langmuir isotherm model fit the equilibrium data well. The maximum adsorption capacities calculated from the Langmuir isotherm model were 46.73 mg/g and 62.54 mg/g for the Sr and Cu ions, respectively. Additionally, the values of thermodynamic parameters such as free energy (ΔG˚), enthalpy (ΔH˚) and entropy (ΔS˚) were determined. The results implied that the prepared PS-FZ beads could be interesting an alternative material for Sr and Cu ion removal.
        3898.
        2016.12 KCI 등재 서비스 종료(열람 제한)
        Zeolite (FZ), prepared from fly ash, was immobilized with polyacrylonitrile (PAN) to fabricate PAN/FZ beads. The prepared PAN/FZ beads were characterized by scanning electron microscopy, thermogravimetric analysis, and Fourier transform infrared spectroscopy. The optimum ratio to prepare PAN/FZ beads was 0.3 g of PAN to 0.3 g of FZ. The diameter of the prepared PAN/FZ beads was about 3 mm. Sr and Cu ion adsorption experiments were conducted with PAN/FZ beads. A pseudo-second-order model fit the kinetic data for Sr and Cu ion adsorption by PAN/FZ beads well. The equilibrium data fitted well with the Langmuir isotherm model, and the maximum adsorption capacities were 96.5 mg/g and 74.6 mg/g for the Sr and Cu ions, respectively. Additionally, the values of thermodynamic parameters such as Gibbs free energy (ΔGo), enthalpy (ΔHo) and entropy (ΔSo) were determined. The positive values of ΔHo revealed the endothermic nature of the adsorption process and the negative values of ΔGo were indicative of the spontaneity of the adsorption process.
        3899.
        2016.12 KCI 등재 SCOPUS 서비스 종료(열람 제한)
        In this study, we investigated the effect of fermentation conditions on the amylolytic and proteolytic activities of Aspergillus luchuensis strain 74-5 and Aspergillus oryzae strain 75-2, which are used in the preparation of the starter culture, for Takju (Korean traditional rice wine). The starter culture was optimized using different conditions, such as inoculum size, inoculation temperature, and incubation time. The enzyme activities under each condition were measured. In the A. luchuensis strain 74-5 starter culture, the α-amylase and glucoamylase activities increased, however the activity of acidic protease decreased as the diluent to starter culture ratio increased. In the A. oryzae 75-2 starter culture, all enzyme activities were maintained at a higher level even at 5% inoculation ratio. Higher enzyme activities were observed in the middle range of inoculation temperature (35, 40℃), than in the lower range (20, 30℃). Enzyme activity in the starter culture varied with incubation time, however it was the highest at 144 and 120 hr, respectively, for A. luchuensis strain 74-5 and A. oryzae strain 75-2. The spore count of the starter culture was approximately 2×107 during fermentation, out of which contamination by aerobic bacteria was about 3×103. The results suggested that the starter culture of each strain could be used as an inoculum for fermentation. However, we needs to conduct further research for the selection of suitable diluting agents
        3900.
        2016.12 KCI 등재 SCOPUS 서비스 종료(열람 제한)
        This study presented the change of quality characteristics of Doenjang with various salt concentrations (4, 8, 15, and 20%) during 12 months. The pHs of Doenjang during fermentation were gradually increased for 12 months, whereas the pHs of Doenjang with 4 and 8% salt increased rapidly. Titratable acidity of Doenjang with 4 and 8% salt was high at initial time, while Doenjang with 15 and 20% salt was high at the 9 and 12 months. The amino-type nitrogen content of Doenjang with 4 and 8% salt was increased and α-amylase activity of all Doenjang was decreased during whole fermentation period. The protease activity of Doenjang with 4 and 8% salt was higher than Doenjang with 15 and 20% salt until 7 months. Total aerobic bacteria number 8.0~9.1 log CFU/g for 12 months, which was steady during fermentation period. Doenjang with 8% salt showed the highest score in umami taste whereas the lowest score in bitterness, astringency, and sourness tastes between 5 and 12 months. In conclusion, Doenjang with 8% salt was a suitable concentration for low-salt fermented foods.