The aging treatment was applied to Rehmannia glutinosa rhizome (RGR) to improve the digestibility by the enzymatic hydrolysis of undigestible sugars. However, RGR spoils easily during the aging treatment. Thus, the purpose of this study was to investigate the influence of ethanol addition as preservatives on sugars and microbial growth of aged RGR. The RGR was treated with the addition of ethanol (0~10%) at 55℃ for eight days. Reducing, free sugars, and total bacterial counts of RGR with ethanol concentrations were analyzed during the aging periods. The aged RGR with 0-2% ethanol appeared spoiled in appearance, and total bacterial counts of these samples increased from 1.1×105 to 2.2×107 CFU and then decreased again. When treated with 4~10% ethanol, the total bacterial counts of aged RGR decreased by more than 99.9% at eight days. In all samples, reducing and digestible sugars increased, and stachyose decreased by the aging treatment. Sucrose content was highest in the 6% ethanol sample (18.2% at six days). These results indicate that the ethanol addition can be applied to the aging treatment of the RGR for improving qualities (sweetness, digestibility, and microbial growth), and can be considered for the stable production of high quality aged RGR.

본 연구는 국내에 자생하는 약용식물인 개똥쑥을 배지 재료로 활용하여 느타리 재배를 위한 적정 혼합비율을 설 정하였다. 개똥쑥의 첨가량에 따른 균사생육과 균사밀도를 조사한 결과 균사생육은 배양 23일 후 개똥쑥 5% 첨 가된 배지에서 12.7 cm였고, 대조구인 포플러톱밥+미강 (8:2)배지에서는 12.5 cm로 개똥쑥 첨가배지와 균사생육이 거의 비슷하였다. 그러나 개똥쑥 첨가량이 증가할수록 대조구 보다 균사생육이 느렸으며, 개똥쑥 70%에서는 2.1 cm로 거의 생육하지 못하였다. 개똥쑥 첨가량에 따른 균사밀도는 처리간에 뚜렷한 차이가 없이 높은 밀도를 보였다. 개똥쑥의 첨가량에 따른 느타리 자실체 특성을 조사한 결과 갓의 직경은 대조구보다 개똥쑥 첨가에서 높았지만, 갓의 두께는 대조구에서 조금 높았다. 대의 두께는 개똥쑥 15% 첨가에서 가장 높았고, 대의 길이는 개똥쑥 10%에서 가장 높았지만 대조구보다는 낮은 경향을 보였다. 수확기 자실체의 갓과 대의 색도를 측정한 결과 대의 L값은 개똥쑥 10%에서 가장 높았고, 갓의 L값은 개똥쑥 5%에서 가장 높은 경향을 보였고, a, b값은 처리간에 뚜렷한 차이가 없었다. 자실체 수량은 대조구가 119 g/850 ml였고, 개똥쑥 5%에서 122 g/850 ml으로 가장 높았고, 개똥쑥 첨가량이 증가할수록 수량은 감소되었다.

BW를 이용하여 느타리를 재배함에 있어 면실박을 대체 할 수 있는 재료를 찾기 위해 시험이 진행되었다. 일반성분 분석에서 BW가 면실박에 비해 단백질 함량은 다소 떨어졌으나 자실체의 생육특성에서 BW 혼합 시 대조구와 수량 등의 생육특성이 유사함을 확인할 수 있었고, 자실 체의 구성아미노산 조성 확인결과 처리구 간 아미노산의 함량은 큰 차이를 나타나지 않았다. 따라서 BW가 느타리 배지제작에 있어 면실박을 대체하여 사용될 수 있을 것으로 판단된다.

The objective of this study was to investigate the quality characteristics of emulsion-type pork sausage manufactured with various levels of Eutrema Japonicum (E. Japonicum)(1, 2, and 3%). The crude fat contents of samples containing 2 and 3% E. Japonicum were 27.46-28.38%, significantly higher than those in the control (p<0.05). The cooking yields samples containing 1 and 2% E. Japonicum were 74.99-75.54%, significantly higher than those in the control (p<0.05). Water holding capacities (WHC) of the samples containing 1% and 2% E. Japonicum were 92.22-92.26% significantly higher than those in the control (p<0.05). while the water losses of sample containing 1% E. Japonicum group was 16.41%, significantly lower than those in the control (p<0.05). And fat losses samples containing 1, 2, and 3% E. Japonicum were 0.03-0.64% significantly lower than those in the control (p<0.05) in emulsion stability. Additionally, viscosity increased with increasing E. Japonicum concentration of E. Japonicum. Texture profile analysis (TPA) showed increased with increasing E. Japonicum concentration for hardness, springiness, cohesiveness, gumminess, chewiness. Thiobarbituric acid reactive substances (TBARS) in the samples containing 2 and 3% E. Japonicum were 0.64-0.69 mg MDA/kg significantly lower than those in the control and 1% E. Japonicum group (p<0.05). These results indicate that emulsion-type pork sausage containing 2% E. Japonicum was increasing WHC, emulsion stability, cooking yield, and was decreasing TBARS compared to other E. Japonicum groups. Therefore, emulsion-type pork sausage containing 2% E. Japonicum is high qualified.

The powder manufacturing process using the gas atomizer process is easy for mass production, has a fine powder particle size, and has excellent mechanical properties compared to the existing casting process, so it can be applied to various industries such as automobiles, electronic devices, aviation, and 3D printers. In this study, a modified A4032-xSn (x = 0, 1, 3, 5, and 10 wt.%) alloy with low melting point properties is investigated. After maintaining an argon (Ar) gas atmosphere, the main crucible is tilted; containing molten metal at 1,000℃ by melting the master alloy at a high frequency, and Ar gas is sprayed at 10 bar gas pressure after the molten metal inflow to the tundish crucible, which is maintained at 800℃. The manufactured powder is measured using a particle size analyzer, and FESEM is used to observe the shape and surface of the alloy powder. DSC is performed to investigate the change in shape, according to the melting point and temperature change. The microstructure of added tin (Sn) was observed by heat treatment at 575℃ for 10 min. As the content of Sn increased, the volume fraction increased to 1.1, 3.1, 6.4, and 10.9%.

The grain growth behavior of M-type Sr hexaferrite (SrM) grains is investigated with the addition of MnCO3. First, the SrM powder is synthesized by a conventional solid-state reaction. The powder compacts of SrM are sintered at 1250oC for 2 h with various amounts of MnCO3 (0, 0.5, 1.0, and 4.0 mol%). There is no secondary solid phase in any of the sintered samples. Relative density increases when MnCO3 is added to the SrM. Obvious abnormal grain growth does not appear in any of the SrM samples with MnCO3. The average grain size increases when 0.5 mol% MnCO3 is added to the SrM. However, as the amount of MnCO3 increase to over 0.5 mol%, the average grain size decreases. These observations allow us to conclude that the growth of SrM grains is governed by the two-dimensional nucleation grain growth mechanism, and the critical driving force for the growth of a grain decreases as the amount of MnCO3 increases.

Phosphorus is an element that plays many important roles in powder metallurgy as an alloy element. The purpose of this study is to investigate the influence of phosphorus addition on the microstructures and mechanical properties of sintered low-alloy steel. The sintered low-alloy steels Fe-0.6%C-3.89%Ni-1.95%Cu-1.40%Mo-xP (x=0, 0.05, 0.10, 0.15, 0.20%) were manufactured by compacting at 700 MPa, sintering in H2-N2 at 1260℃, rapid cooling, and low-temperature tempering in Ar at 160℃. The microstructure, pore, density, hardness, and transverse rupture strength (TRS) of the sintered low-alloy steels were evaluated. The hardness increased as the phosphorus content increased, whereas the density and TRS showed maximum values when the content of P was 0.05%. Based on microstructure observation, the phase of the microstructure changed from bainite to martensite as the content of phosphorus is increased. Hence, the most appropriate addition of phosphorus in this study was 0.05%.

In this study, the effects of Sm addition (0, 0.05, 0.2, 0.5 wt%) on the microstructure, hardness, and electrical and thermal conductivity of Al-11Si-1.5Cu aluminum alloy were investigated. As a result of Sm addition, increment in the amount of α-Al and refinement of primary Si from 70 to 10 μm were observed due to eutectic temperature depression. On the other hand, Sm was less effective at refining eutectic Si because of insufficient addition. The phase analysis results indicated that Sm-rich intermetallic phases such as Al-Fe-Mg-Si and Al-Si-Cu formed and led to decrements in the amount of primary Si and eutectic Si. These microstructure changes affected not only the hardness but also the electrical and thermal conductivity. When 0.5 wt% Sm was added to the alloy, hardness increased from 84.4 to 91.3 Hv, and electric conductivity increased from 15.14 to 16.97 MS/m. Thermal conductivity greatly increased from 133 to 157 W/m·K.

본 연구에서는 국내외 저탄소 녹색성장을 위한 대안으로서 수소에너지와 그 이용 기술에 대한 관심이 높아지는 추세에 발맞춰 무탄소 연료인 수소를 LNG 의 주성분인 메탄, 메탄-프로판, 메탄-프로판-에탄 동축류 확산화염 내에 첨가하여 화염형상 및 연소생성물에 미치는 영향을 확인하였다. 상온상압 조건의 확산화염에 수소를 단계적으로 첨가하여 실제 생성되는 연소생성물의 변화 추이를 가스 분석기를 이용하여 실험적으로 관찰하였고 확산화염의 형상은 디지털카메라를 이용하여 단계적으로 관찰 하였다. 실험결과에서 확산화염에 수소를 첨가함에 따라 질소산화물의 생성량이 선형에 가깝게 증가하는 경향을 보였다. 이것은 수소의 상대적으로 높은 단열화염온도와 빠른 연소속도가 Thermal NOx의 생성을 촉진했기 때문이다. 반면 이산화탄소의 생성량은 감소하는 경향이 나타났는데 수소를 첨가함에 따라 메탄, 메탄-프로판, 메탄-에탄-프로판의 혼합 확산화염에 포함되어있는 전체 탄소비율이 줄어들어 이산화탄소의 생성량이 감소한 것이다. 이는 선박에서 LNG-수소의 혼합 연료사용으로 인해 온실가스인 이산화탄소를 저감할 수 있는 하나의 방안으로 고려될 수 있다는 것을 의미한다.

To investigate Oiji (traditional Korean cucumber pickles) with reduced sodium content based on the use of saline foods as a salt substitute, Oiji was prepared using glasswort powder (Salicornia herbacea L.), and its physicochemical properties and sensory evaluation were examined. The moisture content of Oiji was shown to be higher in those to which glasswort powder had been added compared to the control without addition of glasswort powder, and Oiji with 40% glasswort powder substitute showed the highest pH and lowest acidity, resulting in slow progression of fermentation. The salinity of Oiji among those containing glasswort powder substitute was significantly higher with increasing level of glasswort powder. The sodium content of Oiji was significantly reduced as addition of glasswort powder increased. The L value of Oiji decreased with increased addition of glasswort powder, whereas the a value was highest in the control. The hardness of Oiji was higher in the control than in Oiji containing glasswort powder. Taste acceptance was highest for Oiji with 20% glasswort powder substitute, whereas acceptance of appearance was higher for Oiji with 10% glasswort powder substitute. Flavor and texture acceptance was higher for the control. In the attribute difference test, significant differences were found in brownness, off-flavor, salty taste, and sourness. Based on the findings, 10-20% substitution of salt with glasswort powder did not significantly lower overall acceptance compared to the control while salinity of Oiji was maintained. Therefore, the potential production of low-sodium Oiji has been verified.

Piezoelectric ceramic specimens with the Pb(Mg1/3Nb2/3)0.65Ti0.35O3 (PMN-PT) composition are prepared by the solid state reaction method known as the “columbite precursor” method. Moreover, the effects of the Li2O-Bi2O3 additive on the microstructure, crystal structure, and piezoelectric properties of sintered PMN-PT ceramic samples are investigated. The addition of Li2O-Bi2O3 lowers the sintering temperature from 1,200oC to 950oC. Moreover, with the addition of >5 wt.% additive, the crystal structure changes from tetragonal to rhombohedral. Notably, the sample with 3 wt.% additive exhibits excellent piezoelectric properties (d33 = 596 pC/N and Kp = 57%) and a sintered density of 7.92 g/cm3 after sintering at 950oC. In addition, the sample exhibits a curie temperature of 138.6oC at 1 kHz. Finally, the compatibility of the sample with a Cu electrode is examined, because the energy-dispersive X-ray spectroscopy data indicate the absence of interdiffusion between Cu and the ceramic material.

In this study, we investigated the possibility of using mouse embryonic stem cell conditioned medium (ESCM) and embryonic stem cell medium (ESM) for in vitro maturation in the efficient in vitro production of blastocysts from porcine follicular oocyte. Depending on the concentration of supplement of ESCM added to the NCSU-23 solution did not affect 2-cell development rates and blastocysts development. However, in particular, the survival rate (10 days of culture) of blastocyst was significantly higher than that of the control group as the additive concentration (30%) increased (p < 0.05). The survival rate of blastocysts showed a similar tendency even with addition of ESM (30%) alone. On the other hand, the duration of the addition of these additives during IVM (0-44 h) was that the IVM I period (0-22 h) were more effective than the IVM II period (22-44 h). Thus, the effect of these additives is probably due to the combination of the various physiologically active substances of ESCM or the appropriate amino acids and vitamins of ESM. In particular, these additives were more effective during the first half (IVM I) of in vitro maturation. In summary, optimization of ESCM or ESM supplementation may improve in vitro maturation of porcine oocyte and affect developmental competency. Therefore, if more efficient methods of adding ESCM or ESM to basal culture medium can be developed during in vitro maturation of porcine follicle oocytes, high quality blastocysts will be developed from low porcine follicular oocyte compared to other domestic animals.

느타리버섯 재배에서 영양원으로 가장 많이 사용하고 있는 면실박의 첨가비율은 12%이상이면 충분할 것으로 판단된다. 면실박을 12~18% 첨가된 배지에서는 균사생장량은 13.9~14.0 cm로 균사생장이 대조구와 같거나 조금 빨랐다. 그러나 면실박을 10% 이하 첨가한 배지에서는 대조구보다는 균사생장이 느렸다. 면실박 첨가량에 따른 균사밀도는 처리간에는 뚜렷한 차이를 보이지 않고 높은 밀도를 보였다. CN율은 면실박 2%첨가에서 42.5, 면실박 10%첨가에서 26.8, 면실박 12%첨가에서 25.4였으며, 면실박 16% 첨가에서는 20.4 그리고 면실박 18% 첨가에서는 18로 대조구와 비슷한 수치를 보였다. 갓 직경과 두께는 면실박 14% 처리에서 가장 높았고, 대의 굵기는 면실박 12% 첨가된 처리에서 가장 높았다. 대와 갓의 경도는 면실박 16% 첨가된 처리에서 가장 높았다. 대의 색도를 측정한 결과 L값은 면실박이 적게 첨가된 처리구에서 낮은 경향을 보였지만, a, b 값은 처리간에 뚜렷한 차이를 보이지 않았다. 병당 수량은 대조구가 147.2 g/850 ml였 고, 면실박 12% 첨가에서 147.6 g/850 ml으로 대조구보다 조금 높았다.

In order to study low salinity Oiji (cucumber pickled in salt) with a reduced content of sodium, which was accomplished by replacing the salt in this saliferous food, we produced Oiji using sea tangle and, then performed physicochemical and sensory evaluations. It was found that the moisture content of Oiji was decreased with increasing the amount of added sea tangle. The pH and acidity were significantly different between the samples made with sea tangle, and the pH and acidity showed no consistent tendency according to the amount of sea tangle powder added. The salinity of Oiji was the highest in the control Oiji (2.92%), and the higher the amount of sea tangle added, the lower was the salinity in the Oiji with the salt replaced by sea tangle (2.78 to 2.89%). The sodium content of Oiji was also the highest in the control Oiji (591.65 mg/ 100 g) and significantly decreased with the increasing addition of sea tangle (560.43~366.71 mg/100 g). The color value of Oiji showed a significant difference between the samples, with no consistent tendency according to the amount of added sea tangle powder. The hardness of Oiji was significantly greater in the Oiji with the salt replaced by 40% of sea tangle, with greater hardness noted as the amount of added sea tangle powder increased (217.70 g). As a result of the acceptance test of Oiji, there were significant differences between the samples in overall acceptance, appearance, and taste, showing that the Oiji with salt replaced by 30% of sea tangle was significantly highest in overall acceptance and taste. The attribute difference test showed a significant difference only for the brown color, while no significant differences were found between the samples for off-flavor, bitter taste, fermented taste, salty taste, sour taste, hardness and crispness. The above results demonstrated that when sea tangle was substituted for 30 to 40% of the salt content, the Oiji with a low content of sodium and low salinity can be produced with a high level of taste and overall preference. Therefore, this study firmly demonstrated that 30 to 40% of the salt can be replaced by sea tangle as a substitute in order to produce Oiji that has low salinity, a low sodium content.

와사비 페이스트의 저장성 향상을 위하여 구연산을 농도별로 첨가하고 저장기간에 따른 이화학적 및 미생물학적 특성, 가스발생량 및 ally isothiocyanate 함량 변화를 측정하였다. 와사비 페이스트의 pH는 구연산 첨가량에 따 라 감소하였으며, CA 0.4%처리구에서 4.34±0.01로 가장 낮게 나타났다. 저장기간 동안 와사비 페이스트의 pH는 4.01-5.19사이로 나타났다. 총산의 함량은 저장 7일까지 유의적인 차이가 나타나지 않았으며 저장 14일 이후 감소하였다. 와사비 페이스트의 가용성 고형분 함량은 구연산 첨가량에 따라 증가하였으며, 저장기간에 따른 유의적 차이를 보이지 않고 저장 28일 후 25.60-29.50 oBrix로 나타났다. 저장기간에 따른 와사비 페이스트의 L값은 감소하였으며, a값과 b값은 증가하는 경향을 나타내다. 일반세균 수는 저장기간이 경과함에 따라 감소하는 경향을 나타냈으며, 저장 초기에 2.56±0.09~4.87±0.17 log CFU/g에서 저 장 21일 후 CA 0.30%와 CA 0.40% 처리구에서 일반세균이 검출되지 않았다. 효모의 경우 일반세균의 경우와 마찬가지로 저장기간에 따라 감소하는 경향을 나타내었으며, CA 0.30%와 CA 0.40%의 경우 저장 초기부터 28일까지 검출되지 않았다. 이로써 와사비 페이스트에 구연산 0.30% 이상 첨가하면 미생물의 생장이 억제되는 것을 확인할 수 있었다. 가스발생량은 21일 저장 후 가스 발생량의 증가폭이 가장 크게 나타났으며, 저장 28일 후 19.55-19.80 mL/ tube로 나타났으며, 구연산 처리농도에 따른 유의성은 나타나지 않았다. Allyl isothiocyanate 함량은 구연산 처리 농도 와 저장기간에 따라 감소하였으며, CA 0.40% 처리구에서 저장 초기와 28일 후 각각 45.62±12.78 mg/100 g와 29.72±0.58 mg/100 g로 가장 낮게 측정되었다. 연구 결과 와사비 페이스트에 구연산 0.30%를 첨가하여 제조 시 저장성 향상 효과를 얻을 수 있으며, 이를 통하여 와사비 페이스트의 상온유통 시 유통기한 연장 효과를 얻을 수 있을 것으로 생각된다.