• Asian-Australasian Journal of Animal Sciences
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• 제14권6호
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• pp.844-849
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• 2001

This study was carried out to determine the optimum conditions for cholesterol removal from homogenized milk by treatment with saponin using a response surface methodology (RSM). The effects of temperature, reaction time, and amounts of celite or saponin added on cholesterol removal from milk were investigated. The level of cholesterol removal from milk increased with saponin concentration and varied from 57.4 to 73.3%. The optimum reaction time, amount of celite addition determined by a partial differentiation of the model equation, and amount of saponin addition were 30min, 0.95% and 1.5%, respectively. Under these conditions, the predicted cholesterol removal by RSM was estimated to be 73.4%. The experimental removal value was 73.7%. Thus, there was no appreciable difference between the experimental value and the predicted value based on RSM.

• Asian-Australasian Journal of Animal Sciences
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• 제18권12호
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• pp.1794-1799
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• 2005

The present study was carried out to develop crosslinking of $\beta$-cyclodextrin ($\beta$-CD) using adipic acid, and to determine the optimum conditions of different factors ($\beta$-CD concentration, mixing temperature, mixing time and mixing speed) on cholesterol reduction from homogenized milk. Crosslinked $\beta$-CD was prepared with adipic acid. When the milk was treated with different conditions, the cholesterol removal rate was in the range of 92.1 to 93.1% with 1% $\beta$-CD addition, which were not significantly different among treatments. After cholesterol removal from milk, the used crosslinked $\beta$-CD was washed for cholesterol dissociation and reused. For recycling study, the cholesterol removal rate in the first trial was 92.5%, which was mostly same as that using new crosslinked $\beta$-CD. With repeated ten time trials using same sample, 81.4% of cholesterol was removed from milk. Therefore, the present study indicated that the optimum conditions for cholesterol removal using crosslinked $\beta$-CD were 1% $\beta$-CD addition and 10 min mixing with 400 rpm speed at 5$^{\circ}C$ with over 90% cholesterol removal. In addition, crosslinked $\beta$-CD made by adipic acid resulted in the effective recycling efficiency.

• 한국축산식품학회지
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• 제20권2호
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• pp.101-106
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• 2000

유지방구로부터 분리 정제한 lipase의 활성과 안정성에 미치는 pH의 영향을 야자유와 균질유를 기질로 하여 조사하였다. 효소원으로 buttermilk를 사용하였을 경우는 반응온도 $37^{\circ}C$에서 야자유, 균질유 모두 pH 9.5에서 최대 활성을 나타내었으며, 전형적인 종형의 pH의 존곡선을 나타내었다. 그러나 반응온도 $0^{\circ}C$에서는 pH 10.0까지 활성이 증가하였다. 정제 lipase를 사용한 경우는 반응응도 $37^{\circ}C$에서 균질유를 기질로 사용하였을 때 종 모양의 곡선을 나타내었으며, 최대 활성은 pH 9.0에서 나타났다. 반응온도 $0^{\circ}C$에서는 pH 10.0까지 활성이 계속 증가하였다. BSA를 첨가한 야자유를 기질로 사용한 경우는 반응온도 $37^{\circ}C$, $0^{\circ}C$ 모두 최대 활성이 pH 9.5에 나타났으며, pH 10.0에서는 활성이 현저하게 저하하였다. 정제 lipase의 안정성에 미치는 pH의 증가에 따라 현저하게 저하하였다. pH 10.0에서 $37^{\circ}C$로 20분간 효소를 유지하였을 경우 lipase의 활성은 pH 8.5 때의 활성에 비하여 13%로 감소하였다. 그러나, $4^{\circ}C$에서 60분간 효소를 유지하였을 경우는 lipase 활성이 pH 7.5∼10.0의 범위에서 안정하였다.

• Journal of Nutrition and Health
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• 제9권2호
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• pp.54-58
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• 1976

국내(國內)에서 생산(生産)되는 시유(市乳)와 유제품(乳製品)의 riboflavin함량(含量)을 분석(分析)하고 병우유와 폴리팩우유, 흰우유와 초코렛색의 우유를 대비(對比)시켜 일광(日光)에 예민한 riboflavin의 함량변화(含量變化)를 추적한 결과(結果)를 요약(要約)하면 다음과 같다. (1) Riboflavin의 함량(含量)은 시료 100g당 병우유 흰것 $62.4{\mu}g$, 폴리팩우유 $62.4{\mu}g$, 초코렛우유 $61.5{\mu}g$, 커피우유 $62.5{\mu}g$, 바나나우유 $87.7{\mu}g$, 딸기우유 $89.3{\mu}g$, 발효유 $36.2{\mu}g$, Hard ice cream bar $130.4{\mu}g$, vanilla soft ice cream $195.9{\mu}g$이었다. (2) 한시간 일광(日光)노출후 병우유 72.4%, 폴리팩우유 77,7%, 두시간 경과후 병우유가 92.0%, 폴리팩우유가 91.4%로서 폴리팩우유가 riboflavin이 약간 빨리 파괴되는 경향(傾向)을 보였으나, 두시간 경과후의 파괴율은 서로 비슷하였다. (3) 1시간 일광(日光)노출후 초코렛색 우유는 36.1%, 흰우유는 72.4%, 두시간 후에는 초코렛색 우유 46.3%, 흰우유는 92.0%의 riboflavin의 파괴율을 보여 초코렛우유가 훨씬 파괴율이 적었다. 이상의 결과(結果)로 미루어 특히 여름철의 일광(日光) 노출은 riboflavin의 막대한 손실이 올 수 있음을 알 수 있었고 초콜렛색의 우유가 흰우유 보다 일광(日光)노출에 대한 riboflavin의 보존(保存)에 효과적이었다.

• 한국축산식품학회:학술대회논문집
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• 한국축산식품학회 2002년도 제30차 추계 학술대회
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• pp.179-179
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• 2002

• 한국축산식품학회:학술대회논문집
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• 한국축산식품학회 1997년도 제18차 정기총회 및 학술발표회
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• pp.103-103
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• 1997

• 한국식품영양학회지
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• 제7권4호
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• pp.345-352
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• 1994

High protein beverage of cow-soy milk was prepared by mixing the soymilk and commercial homogenized cow milk in the various ratios. Effect of heat treatment, pH and addition of calcium and sucrose was studied on the water-soluble nitrogen of cow-soy milk The heat-treated soymilk at 10$0^{\circ}C$ were centrifuged at the range of 830~29,900xg for 30 min and 11,200xg was found to be proper for determination of the degree of protein denaturation by centrifugal method. When soymilk was heated at 70~10$0^{\circ}C$ for 30~240 min, soluble nitrogen (QA SN) in supernatant of protein was decreased to 78.0~56.8% due to protein denaturation. Most of heat denaturation of protein was found to be occurred during Initial heating 10$0^{\circ}C$ for all mixed cow-soy milk. The sedimentation of SN was maximum at pH 4.0 In the range of pH 3~8. Addition of sucrose affected little on oASN while calcium addition reduced %SN significantly to approx. 55% for soymilk(100%). The effect of Ca was less as the ratio of cow milk increased.

• Asian-Australasian Journal of Animal Sciences
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• 제14권2호
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• pp.268-275
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• 2001

The effects of homogenization conditions and $\beta$-cyclodextrin ($\beta$-CD) on cholesterol removal of Mozzarella cheese were examined. The homogenization pressure influenced markedly on the cholesterol removal in milk and, 75.64% of cholesterol, the highest rate, was removed at $70.0kg/cm^2$. In addition, an increase in temperature resulted in an increase of cholesterol removal in the range of 71.75 to 78.22%. Among different concentrations of $\beta$-CD addition, 1.0% showed 78.21% of cholesterol removal. Therefore, cholesterol-reduced Mozzarella cheese was made by cheese milk treated with 70 $70.0kg/cm^2$ homogenization at $70^{\circ}C$ and 1% $\beta$-CD addition for a subsequent study. The cholesterol reduction of cholesterol-reduced Mozzarella cheese was 63.92%. Meltability, stretchability and oiling-off in cholesterol-reduced cheese were significantly lower than those in control. Hardness, gumminess and chewiness were significantly reduced, while cohesiveness and elasticity increased. Appearance and flavor of the cheese were superior, but texture inferior to the control.

• Journal of Dairy Science and Biotechnology
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• 제35권3호
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• pp.202-207
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• 2017

본 연구에서는 반응표면분석법을 활용하여 균질 조건, 저장 온도, 저장 기간 등이 유지방의 크림화와 상층부와 하층부의 지방 함량 변화 등에 대해 미치는 영향을 분석하고, 최적의 균질 효율을 갖는 조건들을 예측하고자 실시하였다. 반응표면분석법의 독립변수로는 균질압, 저장 온도, 저장 기간을 설정하였고, -1, 0, 1의 3수준으로 20개의 실험구를 설계하여 종속변수인 creaming, USPHS code, 상층부의 $D_{4,3}$, 하층부의 $D_{4,3}$에 대해 실험을 실시하였다. 반응표면분석과 회귀분석 결과, 균질한 우유의 실험 데이터와 RSM에 의해 예측된 값들간의 상관계수는 0.8 이상의 상관성을 보였다. 반응표면분석의 최적화 결과, $10^{\circ}C$에서 15일의 저장 기간 동안 3 mm 이하의 크림화를 유지하기 위해서는 14 MPa 이상의 균질압이 요구되고, $20^{\circ}C$에서 15일의 저장 기간 동안 3 mm 이하의 크림화를 유지하기 위해서는 17 MPa 이상의 균질압이 요구된다. $10^{\circ}C$에서 15일의 저장 기간 동안 USPHS code를 10% 미만으로 유지하기 위해서는 16.8 MPa의 균질압이 요구되며, $20^{\circ}C$에서 15일 동안의 저장 기간을 유지하기 위해서는 23.1 MPa의 균질압이 요구된다.

• 대한지역사회영양학회지
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• 제1권1호
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• pp.28-40
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• 1996

This study was conducted to evaluate the nutrition quality of the commercial infant formulas and to seek the solution to the establishment of the standard of nutrient requirements for infant formula in Korea. Nutrition informations were obtained from the labels of nineteen commercial infant formulas manufactured by 3 different companies, and the actual amounts of some nutrients were analyzed and compared to the labeled amounts. In addition, the nutrient composition of the commercial infant formulas was compared to the composition of breast milk, RDA for infants, and Codex standard for infant formula. The kind of minerals, vitamins and special components added to the commercial infant formulas were the major differences among 3 manufacturers. For some nutrients, the analyzed amounts were lower than the labeled amounts. In addition when different batches of the same kind of infant formula were analyzed, the large variations in the amounts of certain nutrients were noted. These data suggest that the nutrition labeling informations need to be validated, and nutrients added to the formulas are to be homogenized thoroughly. In order to solve these problems, therefore, like other countries, we need to establish the standard of nutrient requirements for infant formulas. Considering the available data on breast milk composition, RDA for infants and coordination with the international standard, we suggest the adoption of the Codex standard for infant formula may be the best way to manage the nutrition quality of commercial infant formulas at the present time.