• 한국식품조리과학회지
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• 제22권6호통권96호
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• pp.890-897
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• 2006

The aim of this study was to develop muffins with whey protein concentrate (WPC) substituted for fat at the content of 10%, 20%, 40% or 80%. The quality characteristics were compared with those of a full-fat counterpart. With increasing WPC content, moisture, protein, and ash contents increased, fat content decreased, volume and specific volume of muffin decreased, but weight was unaffected. Crust lightness and yellowness of muffins increased, but redness decreased with increasing amount of WPC. Hardness, cohesiveness, springiness, gumminess and brittleness were the highest in muffin substituted with 80% WPC. Results of sensory evaluation indicated that muffin with up to 40% of the butter substituted by WPC was considered to be as acceptable as the control muffin prepared without WPC.

• 전기전자학회논문지
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• 제22권2호
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• pp.393-401
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• 2018

이 논문에서는 WPC / A4WP 무선 전력 전송을 위한 정류기가 설계하였다. 설계된 정류기는 WPC (무선 전력 컨소시엄) 및 A4WP (무선 전력 연합)를 모두 지원하며 전파 브리지 정류기로 설계되었다. WPC는 100kHz ~ 205kHz의 주파수에서 전력을 전송하고 A4WP는 6.75MHz의 주파수에서 전력을 전송한다. 브리지 정류기는 다이오드 대신 MOSFET을 사용하기 때문에 출력 전압이 입력 전압보다 높으면 역전류가 흐르고 효율에 영향을 미친다. 따라서 MOSFET을 통해 흐르는 전류를 감지하고 역전류를 차단하는 역전류 검출기를 추가했다. 주파수 판별기는 주파수 대역이 다르기 때문에 사용된다. 설계된 정류기는 CMOS $0.35{\mu}m$ 고전압 공정을 사용하여 설계되었다. 입력 전압은 최대 18V이며 100kH ~ 205kHz, 6.78MHz 주파수에서 작동한다. 최대 효율은 94.8 %이고 최대 전력 공급은 5.78W 이다.

• 자원리싸이클링
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• 제8권4호
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• pp.57-63
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• 1999

재활용된 농업용 폐비닐과 목재부산물로부터 Wood-Polymer Composites (WPC)을 만들었으며, 또한 LLDPE 및 혼합 polyethylene으로 만들어진 WPC와 비교하였다. 접착성 향상제로 maleic anhydride를 사용하였으며, 이의 개시제로 dicumyl peroixde를 첨가하였다. 접착성 향상제로 maleic anhydride를 사용하였으며, 이의 개시제로 dicumyl peroixde를 첨가하였다. 제조된 WPC의 물성은 인장강도 시험으로 측정하였으며, 목재 및 접착성 향상제의 첨가량에 따라 분석하였다. 또한 파단면을 SEM을 이용하여 분석하였다. 목재의 양이 증가함에 따라 WPC의 신율은 감소하고, 탄성율은 증가하였다. 하지만 인장강도는 MA가 첨가된 경우에만 증가하였으며, MA 1% 첨가로 크게 증가하였지만 더 이상의 첨가는 효과가 없었다. 농업용 재활용 비닐로 제조된 WPC의 물성은 구매된 PE 수지로 제조된 WPC와 비슷한 값을 보였다.

• 한국축산식품학회지
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• 제28권1호
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• pp.105-108
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• 2008

The cell growth and antioxidant activity of Bacillus polyfermenticus SCD were studied in tryptic soy broth (TSB) medium and whey protein concentrate (WPC)-based medium. Overall, higher lactose contents in WPC-35 medium (up to 2.0%), and longer culture times correlated with greater cell viability. In WPC-35 medium with 1.5% and 2.0% lactose, the cell growth of B. polyfermenticus SCD was similar to growth in TSB medium. The 1,1-diphenyl-2-picyrylhydrazyl (DPPH) radical scavenging activity of culture supernatant of B. polyfermenticus SCD in WPC-35 medium was measured to assess antioxidant activity. The antioxidant activity increased up to 32 hr of culture, reaching a maximum of 75.57% DPPH radical scavenging activity. The antioxidant activity seemed to follow the typical kinetics of primary metabolite synthesis. The antioxidant activity of B. polyfermenticus SCD supernatant in WPC-35 medium was more effective and stable than supernatant from TSB medium. These results suggest that WPC-35 medium is effective for the production of antioxidant by B. polyfermenticus SCD.

• Journal of the Korean Wood Science and Technology
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• 제47권1호
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• pp.51-65
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• 2019

A wood-plastic composite (WPC) paver block was manufactured using wood chips waste through an extrusion process, and it was intended to be used for paving in basic rest areas. The first stage in this study covered preliminary tests in terms of flexural strength and dimensional swelling to determine the optimal WPC compounding mix condition, by variation of the WPC ingredients. Next, three different paver blocks including the WPC block, a non-porous cement block, and a porous cement block were tested in terms of various material properties in the laboratory. Finally, two outdoor test sections of the proposed paver blocks were prepared to simulate a basic rest area. Test results indicated that the flexural strength of the WPC paver blocks was about 1.6 times greater than that of the tested cement paver blocks. The WPC block pavement was unaffected by water buoyance as well as volume expansion due to swelling. Results from the impact absorbance test and light falling weight deflectometer (LFWD) test clearly showed that the WPC block paving system marginally satisfied the comfortable and safe hardness range from the pedestrians' perspective, while the results demonstrated that it is structurally sound for application as a road paving block.

• Journal of Dairy Science and Biotechnology
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• 제30권2호
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• pp.93-109
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• 2012

This study was performed to investigate the effects of added whey protein concentrates (WPC) and whey powder (WP) on the quality and shelf life of Tofu, a traditional food in Korea. Combined whey powder and whey protein concentrates were obtained at drainage after the casein was separated by using rennet enzyme or acidification of milk. We manufactured whey Tofu and evaluated its nutritional quality by testing, the general composition for yield, moisture, pH, crude protein, crude fat, carbohydrate, rheology, sensory properties, and change during storage. 1. The general compositions of WPC and WP were as follows: (a) WPC: moisture, 5.9%; crude protein, 56.2%; crude fat, 0.1%; carbohydrate, 32.6%; ash, 5.2%; and pH 5.93 and (b) WP: moisture, 3.7%; crude protein, 13.2%; crude fat, 1.6%; carbohydrate, 74.4%; ash, 7.1%; and pH, 6.65. 2. The yield of Tofu was as follows: (a) in WPC, the content was $CaCl_2$:GDL=6:4 > $CaCl_2$:GDL=9:1 > $CaCl_2$:GDL=7:3 > $CaCl_2$:GDL=8:2 and (b) in WP, 2% addition was the highest (265%) at $13.3g/cm^2$, but with 4% addition WP was the lowest (184%) at $22.2g/cm^2$. 3. The moisture content of Tofu was as follows: (a) in WPC, the content was $CaCl_2$:GDL = 6:4 > $CaCl_2$:GDL=9:1 > $CaCl_2$:GDL=7:3 > $CaCl_2$:GDL=8:2 and (b) in WP, 2% addition was the highest at 79.82% ($13.3g/cm^2$), but 4% was the lowest at 75.18% ($22.2g/cm^2$). 4. The pH of Tofu was as follows: (a) in WPC, the value was WPC 6% > WPC 4% > WPC 2% > control and $CaCl_2$:GDL=6:4 > $CaCl_2$:GDL=8:2 > $CaCl_2$:GDL=9:1 > $CaCl_2$:GDL=7:3 and (b) in WP, WP 4% > WP 2% > control. 5. The ash content of Tofu was as follows: (a) in WPC, the content was $CaCl_2$:GDL=8:2 > $CaCl_2$:GDL=7:3 > $CaCl_2$:GDL=6:4 > $CaCl_2$:GDL=9:1 and (b) in WP, there was no difference between 2% and 4% addition. 6. The crude protein content of Tofu was as follows: (a) in WPC, the content was $CaCl_2$:GDL=8:2 > $CaCl_2$:GDL=7:3 > $CaCl_2$:GDL=9:1 > $CaCl_2$:GDL=6:4 and (b) in WP, there was no difference between 2% and 4% addition. 7. The crude fat content of Tofu was as follows: (a) in WPC, the content was $CaCl_2$:GDL=8:2 > $CaCl_2$:GDL=7:3 > $CaCl_2$:GDL=9:1 > $CaCl_2$:GDL=6:4 and (b) in WP, values decreased with increasing pressed weight. 8. The carbohydrate content of Tofu was as follows: (a) in WPC, the content was $CaCl_2$:GDL=8:2 > $CaCl_2$:GDL=7:3 > $CaCl_2$:GDL=6:4 > $CaCl_2$:GDL=9:1 and (b) in WP, values increased with increasing pressed weight. 9. The rheology test results of Tofu were as follows: (a) in WPC, hardness and brittleness was highest with $CaCl_2$:GDL=8:2 and 6% added WPC. Cohesiveness was highest with $CaCl_2$:GDL=6:4 and 2% added WPC. Elasticity was the highest with $CaCl_2$:GDL=7:3 and the added WPC control. (b) in WP, hardness was the highest with $22.2g/cm^2$ and added WP control. Cohesiveness was the highest with $17.8g/cm^2$ and added WP 2%. Elasticity was the highest with $17.8g/cm^2$ and added WP 4%. Brittleness was the highest with $17.8g/cm^2$ and added WP control. 10. The sensory test results of Tofu were as follows: (a) in WPC, the texture, flavor, color, and smell were the highest with $CaCl_2$:GDL=6:4 and 6% added WPC. (b) in WP, the texture was the highest in the control with $22.2g/cm^2$. Flavor and smell were the highest in WP 2% and $22.2g/cm^2$. Color was the highest in WP 2% and $17.8g/cm^2$. 11. The quality change of Tofu during storage was as follows: (a) in WPC, after 60 h, all samples began to get spoiled and their color changed, and mold began to germinate. (b) in WP, the result was similar, but the rate of spoilage was more rapid than that in the control.

• Journal of Dairy Science and Biotechnology
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• 제31권1호
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• pp.35-49
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• 2013

The purpose of this study was to develop Mozzarella cheese analogues by using dairy products in the form of WPC 34, WPC 80, whey protein, demineralized whey powder, and lactose powder along with soy milk. Soy milk was separately blended with 5% WPC 34 (A), WPC 80 (B), DWP (C), WP (D), and LP (E) and also with 10% WPC 34 (F), WPC 80 (G), DWP (H), WP (I), and LP (J). Blending of soy milk and whey products showed that increase in the proportions of whey products (WPC 34, WPC 80, DWP, WP, and LP) led to increase in the protein, lactose, and SNF levels of the admixture. A decrease in fat content was observed for all cheeses prepared from mixtures, relative to those for the control cheese. The nitrogen content within analogue samples was higher than that in the control cheese and increased with increase in the proportions of whey products within soy milk. Higher water soluble nitrogen levels were observed in cheese prepared from whey-product-blended soy milk than in the control cheese. The non-protein nitrogen level within the control Mozzarella cheese was significantly lower than that in the Mozzarella analogues, and, in the case of cheese analogues, it increased with increase in the proportion of whey products in soy milk. With regard to the physicochemical and sensory qualities of the Mozzarella cheese analogues and control cheese, the pH of all analogue samples, with the exception of the cheese prepared from group G, was lower than that of the control Mozzarella cheese. Rheological studies showed that the hardness of Mozzarella cheese analogues was lower than that of the control Mozzarella, while the elasticity, cohesiveness, and brittleness of the analogues was higher. The control sample had a higher meltability level than any of the Mozzarella analogues. Mozzarella cheese prepared with the traditional method had higher browning and stretching levels than all the cheese analogues, but a lower oiling-off level.

• Journal of the Korean Wood Science and Technology
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• 제42권6호
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• pp.682-690
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• 2014

본 연구에서는 WPC의 열안정성을 향상시키기 위해 폴리프로펠렌 매트릭스에 목분과 폴리인산염(ammonium polyphosphate, APP)의 삼종혼합 후, 목분과 난연제 첨가에 따른 목재플라스틱 복합재(wood plastic composites, WPC)의 열분해 거동이 조사되었다. 모든 배합비의 WPC 열분해 거동은 질소의 환경에서 분당 $10^{\circ}C$ 상승속도로 제어하여 열중량분석기(Thermogravimetric analyzer)를 통해 분석하였다. 목분의 열분해온도가 PP의 열분해온도 보다 낮기 때문에 목분에 의해 생성된 char막은 PP로의 열전달 속도를 낮추며, 2차 열분해온도 증가 및 열분해속도를 늦춘다. APP를 첨가한 WPC의 경우 1차 열분해온도 감소 및 2차 열분해온도의 증가를 보여준다. 목분의 함량이 높은 WPC의 경우, APP 첨가 시 1차 열분해온도 감소 및 2차 열분해속도가 증가하였고, 고온에서 잔여물의 양은 APP 함량이 증가할수록 크게 증가하였다. APP가 첨가된 WPC 경우, 목분의 함량이 10 wt%에서 50 wt%로 증가 시 고온에서 잔여물 양이 증가하였는데, 이는 APP 및 목질섬유의 char화가 동시에 발생되기 때문으로 보이며 결과적으로 목분 함량이 증가할수록 APP의 효과가 높게 나타나 열안정 효과를 관찰할 수 있었다.

• 한국식품과학회지
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• 제30권4호
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• pp.988-991
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• 1998

소와 돼지 혈액중의 혈장 단백질을 분리하여, 성분 분석과 단백질 함량을 정량했으며 혈장단백질의 식품 기능성에 관하여서는 기존 유화제로서 활용되는 유청 단백질인 WPC와 비교하여 유화능력을 비교 검토하였다. FPLC 및 SDS-PAGE에 의한 성분분석 결과 혈장 알부민(SA)은 돈혈장단백질(PPP), 우혈장단백질(BPP), 유장단백질(WPC)의 순서로 많이 함유되었으며, 혈장 단백질에는 ${\beta}-globulin$분획(주로 transferrin)이 다량 포함되어 있고, 그외 미량성분(fibrinogen, immunoglobulin)들이 확인되었다. 단백질 함량은 BPP (85%) 및 PPP (82%) 모두 높은 함량을 보여 우수한 단백질원으로 이용 가능할 것으로 보였다. 유화력도 혈장단백질들이 단백질 농도 2% 이하에서는 WPC보다 높았으며, 4% 이상에서는 WPC보다는 약간 낮았다. 또한 염농도 및 pH 의존성에 관하여 유화력에 미치는 영향을 검토한 결과, PPP 및 BPP의 pH 영역에 대한 유화활성은 WPC와는 상이하게 산성쪽의 pH에서 염기성쪽보다 더 높은 활성을 보였으며, 염(NaCl)첨가로 인한 유화 활성의 영향은 WPC와 비교하여 pH 의존성이 상당히 높았으며, 특히 산성쪽에서 높은 활성을 나타냈다. 이상의 결과들을 살펴볼 때 소 및 돼지의 혈액에서 제조한 혈장단백질들은 우수한 유화특성을 갖는 식품소재로 확인되었다.

• 석유와에너지
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• 1호통권222호
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• pp.101-104
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• 2001