본 연구에서는 굵은 골재 특성이 콘크리트 건조수축에 미치는 영향을 평가하기 위하여 높은 밀도를 가진 전기로 산화슬래그를 굵은 골재로 사용하여 콘크리트 건조수축 시험을 진행하였다. 실험 결과, 전기로 산화슬래그를 굵은 골재로 적용한 콘크리트의 경우 일반 골재를 사용한 콘크리트에 비해 건조수축 발생량이 저감되었으며, 이는 일반 골재에 비해 높은 밀도를 가진 전기로 산화슬래그의 물리적 특성에 기인한 것으로 사료된다.

In this study, the combustion characteristics were investigated based on the biodrying solid recovered fuel (SRF) in a 5 Ton/day scale combustion boiler. The composition of the combustion gas containing the biodrying SRF was analyzed, the particulate matter, and its HCl content was determined with the air pollutant process test method. Mass balance, carbon balance, and combustion efficiency were calculated according to the equivalence ratio (ER) method; the energy recovery efficiency of the combustion boiler was also analyzed. The overall combustion efficiency of the biodrying SRF was 97.3 % and the energy recovery efficiency was 80.2%.

Recently, the Ministry of Industry has made efforts to expand renewable energy by 2030, and the Ministry of Environment has sought to revitalize solid fuels from livestock manure, which is a type of bio-energy source, such as reviving laws to activate solid livestock fuels. However, the operating costs of fuel-manufacturing facilities must be reduced to activate solid livestock fuels. The proper dryer must be selected to reduce the drying cost, which comprises the majority of the operating expenses. Laboratory-scale experiments were conducted to confirm the possibility of drying cow manure, the feasibility of utilizing waste heat and the existence of an adhesion solution. Some adhesion phenomena were detected from the disk-dryer results. However, this phenomenon disappeared when the water content of the cow manure was below 50%. A water content of 41% was used to confirm this adhesion phenomenon in the cow manure. Because of the high viscosity of cow manure, a recycling method had to be applied through the disk to match the water content in the dryer. A drying test with a duct rotary dryer confirmed that waste heat that is generated from power plants can be utilized to lower the moisture content of solid fuels in livestock waste to 20%.

This study compared the quality and drying characteristics of dried king oyster mushroom (Pleurotus eryngii), shiitake mushroom (Lentinus edodes GNA01) and maitake mushroom (Grifola frondosa) slices obtained by sundrying, hot-air drying (40, 50, 60 ), low-temperature vacuum drying (20, 25, 30 ), heat-pump dehumidifying drying (30, 40, 50 ), and freeze drying. The quality changes investigted included color, browning degree, hardness, general components, -glucan. Color changes in king oyster mushroom during freeze drying were β less than that between control (raw) and treated mushrooms. Compared with other drying methods, low-temperature vacuum drying of shiitake mushroom resulted in less color changes. Browning degree differed significantly between the different drying methods. As temperature increased, low-temperature vacuum drying resulted in decreased browning while heat-pump dehumidifying drying resulted in increased browning. In king oyster mushroom, hardness increased with temperature under hot-air drying, low-temperature vacuum drying and heat-pump dehumidifying drying. In shiitake mushroom, hardness increased with increasing temperature under hot-air drying and heat-pump dehumidifying drying. β-glucan content after drying was found to be between 28.29 and 39.39% in king oyster mushroom, 23.05 and 29.48% in shiitake mushroom and 16.10 and 24.51% in maitake mushroom.

The study attempted to investigate the variation in the quality of the yellow paprika according to the duration of the yellow paprika and to use the basic materials for the development of various processed foods. The moisture content of dried paprika was 11.19% on the freeze-drying paprika (FD), and the amount of water was increased by 18.19% on the 15th day of the storage cycle. The pH has been significantly changed depending on the length of the storage period, and the sugar content in FD. The acidity contents was increased during storage in all dried paprikas showed the highest acidity, but hot air-drying paprika(HAD) was lowest in the acidity. The L value was decreased during storage period from the paprika outside and inside. The a value was not significantly dependent on the length of storage period from paprika outside and inside, and the b value increased the during storage period from paprika outside and inside. The texture of strongness, hardness, chewiness, and brittleness were decreased during storage period from all drying paprika except for FD, showing the increasing trend in cohesiveness, springiness, chewiness, and brittleness. The total aerobes changes was the lowest in HAD.

저온 적응성 효모 SCY297의 종균 방법에 따른 생존율과 약주 제조시 양조 특성을 조사하였다. 동결건조, 송풍건조 및 액체 제형 방법으로 제조한 다음, 실온에서 장기 저장에 따른 효모의 생존율과 양조 특성을 비교하였다. 또한, 부형 제로 skim milk, α-lactose, trehalose를 5%씩 첨가하여 생존율과 양조특성에 미치는 영향을 조사하였다. 부형제가 첨가된 동결건조 및 액체 제형 SCY297 효모는 실온에서 15주 까지 약 80% 이상의 생존율을 나타내었고, 송풍건조는 skim milk 첨가한 경우만 약 80% 이상 생존율을 나타내었다. 저장기간 및 제형화된 효모 SCY297로 약주를 발효하여 그 술덧을 분석한 결과, 동결건조 및 송풍건조된 SCY297는 무처리 SCY297보다 적정산도는 0.61, 아미노산도는 14.23 증가하였고, 알코올 함량은 5.07% 감소하였다. 액체 SCY297는 무처리 SCY297보다 pH 1.86, 아미노산도는 5.1 증가하였고, 알코올 함량은 2.9%로 감소량이 낮았다. 따라서 본 연구 결과, 종래의 고상형 방법보다 액상형 방법을 통한 종균화 가능성을 제시하였다.

This study was carried out to investigate the economic and environmentally friendly process of drying sludge by combining a mechanical dewatering filter press and thermal dryer. The dryer for 40 kg/hr of dewatered sludge consisted of a main dryer, a heat exchanger, a pre-dryer, and supplementary equipment. During the dewatering process, 100 kg of sludge with 80.11% water content was diluted and mixed with 400 kg of water and ferric chloride solution was added as a sludge conditioner. The average water content of dewatered sludge cake was 60.9% and the energy consumption rate (ECR) for removing water was 226.9 kcal/kg-H2O. Hot flue gas generated from the main dryer was utilized as heating air for the pre-dryer in the heat exchanger. When 36 kg/hr of dewatered sludge cake was dried, the ECR was 1,009 kcal/kg-H2O with 3.96% water content. The combined operation of the dewatering and the thermal drying processes showed that the ECR was reduced sharply to 521 kcal/kg-H2O. The high humidity gas generated from each drying unit in the main dryer was recirculated to the odor decomposition chamber in the main dryer to destroy odor components at a high temperature. The odor concentration of humid gas generated by the pre-dryer was very low due to the relatively low operating temperature.

The aim of this study was to investigate the characteristics of paprika dried by various methods. Moisture content of dried paprika was higher in vacuum freeze-dried red paprika (DRP) (11.85%) than in vacuum freeze-drying of osmotic dried red paprika in sugar (RPS), vacuum freeze-drying of osmotic dried red paprika in fructose (RPF) and vacuum freeze-drying of osmotic dried red paprika in corn syrup (RPCS). Carbohydrate content of DRP was the lowest among the dried groups, but fat, protein, and ash contents were the highest in DRP. The pH of paprika was the highest in RPF (5.34), while it was the lowest in DRP (5.05). Reducing sugar and sugar contents of RPF were 28.59 g/100 g and 5.03 °Brix, respectively, which are the highest level among the groups. All color values in inside of paprika were the highest in RPCS, while in outside of paprika, L value is the highest in RPCS, and the value of a, b were the highest in RPS. Regarding the texture characteristics of paprika, strongness, hardness, adhesiveness, chewiness and brittleness were the highest in RPS (p<0.05).

The purpose of this study was to evaluate the effect of superheated steam drying on physicochemical and microbial characteristics of Korean traditional actinidia (Actinidia arguta) leaves. Actinidia leaves were dried at steam temperature of 350℃ and oven temperature of 150℃ for 40-200 sec. Moisture content and water activity decreased with increasing the drying time, while color values including L, a, and b values and total color difference (ΔE) increased as drying time increased. The relationship between moisture content and water activity showed an exponential fit with high correlation vlaue (R2=0.9909). Total phenolics and flavonoids content and antioxidant activity such as DPPH radical scavenging activity, ABTS radical scavenging activity, and FRAP assay of dried actinidia leaves increased with increasing the drying time up to 160 sec, but dramatically decreased at drying of 200 sec. The numbers of total areobic bacteria of leaves was not detected at drying time over 120 sec and coliform of all the samples was not detected. As a results, the superheated steam was an very effective drying method of increase to the nutritional and sanitary quality of dried Korean traditional actinidia leaves.

생활폐기물 및 산업폐기물로부터 고형연료를 제조하는 과정에서 폐기물 반입량 대비 30 ~ 45%의 비율로 잔재물이 발생되어 매립되거나 일부는 소각장으로 반입되어 처리되고 있다. 이러한 잔재물은 함수율 40% 이상을 나타내어 그대로 매립되었을 경우 오염부하를 증가시킬 수 있으며, 매립에 의한 처분비용으로 전체 시설 운영비의 약 20%가 요구되는 실정이다. 이러한 잔재물은 양 및 질적인 측면에서 볼 때 추가 공정을 통하여 충분히 고형연료로 생산이 가능하다. Bio-drying 기술은 폐기물 내에 존재하는 생분해성 유기물질에 대한 미생물의 호기성 분해열을 이용하여 폐기물의 수분을 건조시키는 건조에너지 소모 및 설치/운영비를 최소화 할 수 있는 경제성이 우수한 기술이다. 본 연구에서는 고형연료화 시설에서 발생된 잔재물을 대상으로 Bio-drying 기술을 적용시켜 생산된 비성형 고형연료의 벤치규모 연소실험을 통해 연소 공기비에 따른 바닥재와 비산재의 발생 특성을 고찰하였다. 또한 기존 시중에 판매되고 있는 비성형 고형연료와의 연소특성 비교/분석을 통해서 Bio-dyring 고형연료의 연소특성을 파악하고 연소 조건의 최적화를 진행하였다. Bio-drying 고형연료와 판매용 고형연료의 연소 바닥재의 XRF 분석 결과 CaO, SiO2, Al2O3, Fe2O3가 주성분을 이루며 그 중에서 CaO 성분이 각각 36.6%와 48.6%로 가장 높게 나타났다.

고로슬래그 미분말은 공학적으로 우수한 건설산업 부산물이며, 최근들어 환경부하 저감 및 사용 활성화를 위해 대단위 슬래그 치 환 콘크리트가 많이 연구되고 있다. 본 연구에서는 목표 강도를 50 MPa로 설정하고 고로슬래그미분말 치환률을 65%로 고려한 대단위 치환 슬 래그 콘크리트를 제조하여 건조수축특성과 초지재령 특성을 평가하였다. 이를 위해 3 수준의 콘크리트를 제조하였으며, 슬럼프 플로우, 강도, 건조 및 자기수축에 대한 실험을 수행하였다. 실험결과, 보통 포틀랜트 시멘트를 100% 함유한 콘크리트(OPC 100)에 비하여 재령 7일전의 강 도는 약간 감소하였으나, 슬래그 치환 배합은 수화에 필요한 충분한 자유수를 가졌으므로 28일 재령에서는 우수한 강도 발현을 나타내었다. 또 한 재령 3일까지 큰 자기수축으로 인하여, OPC 100 배합에서는 건조수축이 크게 평가되었지만, 65% 고로슬래그 미분말을 치환한 배합에서는 초기재령의 자기수축 성능이 개선되어 우수한 건조수축거동을 나타내었다. 특히 단순 질량 치환배합(BS 65)보다 물-결합재비(0.27)와 단위수 량(163kg/m3)을 낮춘 OPTBS 65에서 더욱 우수한 건조수축 및 자기수축 거동을 나타내었다.

The purpose of this study is to understand a compressive strength and propose a dry shrinkage strain equation being able to predict dry shrinkage of alkali-activated materials(AAM) mortar samples manufactured using fly-ash(FA) and ground granulated blast furnace slag(GGBFS). The main parameters investigated were the GGBFS replace ratios(30, 50, 70 and 100%) and sodium silicate modules(Ms[SiO2/Na2O] 1.0, 1.5 and 2.0). The compressive strength of AAM increased with increases GGBFS replace ratios or Ms contents. The dry shrinkage strain of AAM decreased with increases Ms contents. But, the dry shrinkage strain of AAM increased as the GGBFS replace ratio increases. Therefore, the GGBFS replace ratio seems to have very significant and important consequences for the mix design of the AAM mortar. The results indicated the R-square of single regression analysis based on each mix properties was the highest value; 0.7539~0.9786(average 0.9359). And the presumption equation of dry shrinkage strain with all variables(GGBFS, Ms and material age) has higher accuracy and its R-square was 0.8020 at initial curing temperature 23 degrees Celsius and 0.8018 at initial curuing temperature 70 degrees Celsius.

전 세계적으로 에너지 수요증가와 유가 불안정 현상이 지속됨에 따라 이를 대체할 방안으로 신재생에너지 사용에 대한 관심이 높아지고 있으며 신재생 에너지의 수요가 늘어날 것으로 예측된다. 우리나라는 신재생에너지 공급의무화 제도(Renewable & Portfolio Standards; RPS)를 2012년부터 도입하여 50만kW 이상의 발전소는 총 발전량에 대한 신재생에너지를 사용한 전력공급율을 2012년 2%를 시작으로 2024년까지 10%로 실시할 계획이다. 최근 RPS 의무이행자인 발전사들의 신재생에너지발전원 중 바이오 비율이 70%에 이르며 이는 바이오매스 발전이 투자비 및 연료구매 비용이 낮고 운영효율성이 높아 RPS 이행이 쉽기 때문이다. 하지만 바이오매스로의 쏠림현상은 국내 목재시장의 유통구조에 악영향을 미치고 있으며 바이오매스발전 급증으로 폐목재 수요도 동반 증가하면서 재활용 가능한 목재까지 연료로 사용되고 있는 실정이다. 최근 팜오일 바이오매스는 인도네시아 산업을 이끌 잠재력 있는 자산으로 대두되어 왔으며, 2013년 기준 1억 4,200만 톤의 팜오일과 이에 따른 6,654만톤의 팜 부산물이 생산되고 있어 이를 연료화시 국내에서 거론되고 있는 바이오매스 문제를 해결할 수 있는 신재생에너지원으로써 확보가 가능할 것으로 판단된다. 본 연구에서 대상으로 하는 EFB는 팜오일 생산과정에서 발생되어 일부분만 비료로 사용되고 처리되지 못해 야적되어 있는 것을 사용하였다. 3ton/day급 Pilot급 일체형 다단건조 탄화기를 사용하여 고열량인 EFB(저위발열량 : 4,320 kcal/kg)를 반탄화 고형연료로 생산하기 위해 반탄화 온도(200~300℃)와 시간(30~60분)을 고려하여 고형연료 생산량 및 발열량에 미치는 영향에 대하여 검토하였다. 반탄화 온도 변화에 따라 EFB의 저열량휘발성분의 감소와 탄소함량의 증가로 발열량(5,150 kcal/kg)이 증가하는 경향을 나타나는 것으로 분석되었다. 본 연구로 최적 EFB 반탄화 고형연료 생산인자를 도출함에 따라 경쟁력 있는 바이오매스 신재생에너지로 확보 될 것으로 전망된다.

In this study, the drying characteristics of medicinal (Ganoderma lucidum, Phellinus linteus) and edible (Pleurotus eryngii, Lentinus edodes) mushrooms were investigated. Their shrinkage ratios, Hunter’s color values, and rehydration ratios were evaluated. Mushrooms were cut with rectangular (1 cm) and square (1×1 cm) shapes, and dried in the room temperature and at 50℃ and 70℃ using hot-air dryer. Initial moisture contents of edible mushrooms were higher than those of medicinal mushrooms, whereas final moisture contents were vice versa. Drying rate was the highest when drying at 70℃ (p<0.05). Moreover the drying rate of square slices was higher than that of rectangular slices (p<0.05). The shrinkage ratios of both medicinal mushrooms and edible mushrooms were the least when drying at 50℃ and 70℃, respectively (p<0.05). The changes of color values were less in the medicinal mushrooms dried in the room temperature than in the hot-air dried medicinal mushrooms (p<0.05). However, in case of edible mushrooms, the changes of color values were less in the hot-air dried mushrooms (p<0.05). Rehydration ratios of medicinal mushrooms dried at 50℃ was the highest (p<0.05). In contrast, rehydration ratios of edible mushrooms was the highest when drying in the room temperature (p<0.05). Thus, the hot-air drying at 50℃ would be suggested as the efficient drying method for both medicinal mushrooms and edible mushrooms.

This study was designed to compare the quality characteristics of spray-dried (SD) and freeze-dried (FD) Pueraria thunbergiana extracts powder hot water extracts. Quality characteristics of the SD and FD powder including moisture content, color value, water absorption index, water solubility index, dynamic angle and antioxidant activities were evaluated. The moisture content of SD powder (1.50%) was lower than that of FD powder (2.92%). L* and b* values of SD powder was lower than of FD powder. The water absorption index was higher in FD powder (1.40) and water solubility index in SD powder (94.10%) was higher than that FD powder (90.69%). Dynamic angle of SD powder (36.46°) was higher than that of FD powder (33.30°). The DPPH radical scavenging activities of 5 mg/mL solution of SD powder and FD powder were 85.38 mg/mL, 59.38 mg/mL, respectively. And, the same trend was observed for the ABTS radical scavenging activities of the drying powder as that observed for their DPPH radical scavenging activities. There were relatively higher contents of phenolic compounds in SD powders than in FD powders. In conclusion, spray-dried Pueraria thunbergiana extracts showed the high WSI, polyphenol, DPPH and ABTS radical scavenging activities and low moisture content and dynamic angle than freeze dried powder.

This study was performed in order to provide basic data for predicting the usefulness of Jicama (Pachyrhizus erosus) as a food raw material. The changes in the physicochemical properties of freeze-dried and hot air-dried Jicama were investigated and analyzed. The moisture content of raw Jicama was 81.84%. The crude protein, crude fat, crude ash and carbohydrate content of hot air-dried Jicama powder were 2.85, 0.79, 7.93 and 88.44%, while those of freeze-dried Jicama powder were 3.93, 0.83, 7.92 and 87.32%, respectively on dry basis. Regarding the color values, the lightness of freeze-dried Jicama (92.86) was higher than that of the hot air-dried Jicama (88.01), whereas the redness (-0.67) and yellowness (3.21) of freeze-dried Jicama were lower than those of the hot air-dried Jicama (0.43) and (11.96), respectively. The brown index was lower in the freeze-dried Jicama (0.029) than in hot air-dried Jicama (0.107). The total sugar content showed no significant differences between freeze (46.49 mg/g) and hot air-dried Jicama (45.11 mg/g). Finally, the amylose content was higher in freeze-dried Jicama (5.66%) than in hot air-dried Jicama (6.63%).

본 연구에서는 부재료를 첨가하지 않는 건 블루베리를 제조기술을 확립하고자 건조 온도를 달리하여 건 블루베리의 품질변화와 항산화 특성을 조사하였다. 즉, 건 블루베리 제조는 건조 온도에 따라 A(40℃, 72시간), B(40℃, 48시간 및 50℃, 24시간), C(50℃, 72시간), D(60℃, 72시간)로 하였다. 건 블루베리의 수율을 측정한 결과 17.73~31.17%의 범위이었으며 건조 온도가 낮을수록 유의적으로 높게 나타났다(p<0.05). pH는 A가 가장 높았으며 가용성 고형분 함량은 건조 온도가 높을수록 유의적으로 높아지는 것으로 나타났다(p<0.05). 수분함량 및 수분활성도는 건조 온도가 높을수록 낮아지는 경향으로 나타났다. 색도를 측정한 결과 L값은 건조 온도가 낮은 A가 높게 나타난 반면 a값 및 b값의 경우는 건조 온도가 높은 D가 높게 나타났다. 건조된 건 블루베리의 색도는 건조 온도가 높을수록 건조는 빨리 되었지만 육안으로 보았을 때 과피의 색이 주황색으로 변하여 상품으로 적절하지 않았다. 조직감 변화는 경도(hardness), 점성(gumminess) 및 씹힘성(chewiness)은 건조 온도가 높을수록 높은 값을 나타내었으며 탄력성(springiness)과 응집성(cohesiveness)은 비슷한 경향으로 건조 온도가 높을수록 약간 증가하는 경향이었지만 유의적인 차이는 없었다(p<0.05). 관능적 특성에서 전반적인 기호도는 B > A > C > D순으로 평가되었다. 항산화 특성으로 총 폴리페놀 함량과 DPPH radical 소거능을 측정한 결과 건조 온도가 낮을수록 항산화 활성이 높게 나타났다. 따라서 건 블루베리 제조에 적당한 처리군은 B로 열풍건조 온도를 40℃로 하여 48시간 건조 후 온도를 50℃로 높여 24시간 동안 건조하는 것이 품질이 우수한 상품과 형성율을 높이는데 좋을 것으로 생각된다.

Mechanical Biological Treatment (MBT), widely spread in Europe, is a process combined with mechanical separation and biological treatment. This is an alternative technology that can accomplish WtE (Waste-to-Energy) and landfill diversion. Bio-drying, aimed to produce high quality SRF, focused on removing moisture of waste through generated heat when biodegradable organic material is partially degraded by micro-organism. However, most of SRF production facilities in Korea consist of mechanical treatment. In those, 40% of input waste have been generated as residue disposed of in landfill. As a result of physico-chemical characteristic analysis of residue from target facilities, composition of food wastes, papers and plastics ranged 6.7 ~ 18.3%, 9.1 ~ 17.3%, and 5.8 ~ 12.2%, respectively. The moisture content of residue was about 43%, and low heating value was analyzed a range of 1,300 up to 1,900 kcal/kg. Results showed that combustible material having potential to produce SRF is discarded and the amount of biodegradable material such as food waste is still large. Therefore, we assumed it may cause pollution in terms of landfill gas emission and high concentrated leachate generation. In this study, recent trends of Bio-drying is discussed as the alternative technology to solve problems at SRF production facilities in South Korea.

아로니아의 활용성 제고를 위하여 건조방법에 따른 품질 특성을 비교한 결과, 건조과정 중 중량변화율은 진공동결 건조가 81.6%로 가장 많은 중량감소를 나타내었고, 수분함 량은 진공동결건조에서 가장 많은 수분이 감소하였으며, 건조 후 최종 수분함량은 진공동결건조에서 0.99%로 가장 낮은 함량을 나타내었다. 색도 측정결과, L*값은 건조방법 에 따른 큰 차이를 나타내지 않았으며, a*값과 b*값은 진공 동결건조와 냉풍건조에서 증가하였고, 열풍건조에서는 감 소하였다. 경도는 열풍건조에서는 건조 36시간 이후 급격 하게 증가하였고, 냉풍건조는 서서히 증가하다가 132시간 이후 급격하게 증가하는 모습을 보였다. 건조방법에 따른 품질특성으로 건조수율은 냉풍건조가 24.20%로 가장 높았 으며, 열풍건조 20.40%, 진공동결건조 19.41% 순으로 나타 났다. 일반성분은 생과에서 수분이 61.76%로 가장 높게 나타났으며, 조회분은 열풍건조에서 가장 높게 나타났고, 가용성무질소물, 조단백, 조지방은 진공동결건조에서 가장 높은 함량을 나타내었다. 건조방법에 따른 아로니아의 pH 는 3.84~3.92로 큰 차이가 없었으며, 당도는 동결건조 (6.57°Brix) > 열풍건조(5.37°Brix) > 냉풍건조(4.40°Brix) > 생과(1.07°Brix) 순으로 나타났다. 무기질 함량은 진공동 결건조에서 가장 높았으며, 주요 무기질은 K, Ca, Mg, Na인 것으로 나타났다. 아로니아에 함유된 당은 fructose, glucose 두 종류인 것으로 나타났으며, 진공동결건조가 20.59 g/100g으로 가장 높은 함량을 가진 것으로 나타났다.

In order to produce the high quality of dried-ear mushroom, various drying methods such as hot-air drying at 40~80˚C, freeze drying and drying in vinyl house were carried out. Drying hours of hot-air drying, freeze drying and drying in vinyl house were 12.5~21.5, 36.0 and 72.0 hrs, respectively. Vitamin D2 content of sample was the highest as 6.77μg/g DW in drying in vinyl house and then followed by freeze drying as 5.90μg/g DW and hot-air drying as 1.89~5.01μg/g DW. After dry, external appearance and color of mushrooms applied hot-air drying and drying in vinyl house were better than freeze-dried one. After rehydration, water uptake of sample in drying in vinyl house and hot-air drying at 50~60˚C were 17.8 and 19.3~21.0 times, respectively. The methods of drying in vinyl house and hot-air drying at 50~60˚C also led to high hardness, good shape and resilience. As the results of production of dried-ear mushroom with high quality, we suggest that the best method for drying is the drying in vinyl house due to not only high vitamin D2 content, good external appearance and color after drying but also high hardness and good shape after rehydration.