• 한국축산식품학회지
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• 제23권1호
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• pp.63-69
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• 2003

본 연구는 단백질분해효소로 whey protein을 가수분해하여 얻은 가수분해물의 용해도와 유화특성의 변화를 측정하기 위해 실시하였다. Whey protein concentrates를 porcine trypsin(E : S=1 ; 3,000)으로 pH 8.0, 37$^{\circ}C$에서 6시간 동안 가수분해한 whey protein 가수분해물의 유화활성은 분해 4시간째에 가장 높게 나타났으며, 이 때 가수분해도는 5.50%이었다. whey protein의 효소가수분해로 whey protein 중의 $\alpha$-lactalbumin은 분해가 잘 일어나지 않으나 $\beta$-lactoglobulin은 분해 초기부터 급속히 분해되며 유화력 상승에 관여하는 여 러개의 저분자량 peptide를 생성하였다. 가수분해물의 용해도는 가수분해시간이 지남에 따라 증가세를 보이다가 5시간부터 조금씩 감소 추세를 보였으며, pH에 따라서는 등전점 부근인 pH4~5에서 용해도가 가장 낮았으나 가수분해시간이 증가함에 따라 이 부근의 용해도가 현저히 증가하였으며 pH 6이상에서는 pH가 증가함에 따라 용해도도 증가하였다. 유화활성은 용해도의 결과와 거의 비슷한 결과를 나타내었다. 유화 안정성은 분해시간이 지남에 따라 조금씩 증가함을 보여주었으나, 가수분해 4시간부터 pH 8 이상의 PH에서 급격한 증자를 나타내었다.

• 한국응용과학기술학회지
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• 제33권1호
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• pp.155-167
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• 2016

Surface-active substances in defatted rapeseed cake were obtained using a supercritical fluid extraction method. Then, it was purified by removing sinapine in the extract through a series of steps using a mixed solvent: diethyl ether and ethyl acetate (1:1, v/v). Emulsifying properties of purified surface-active substances were investigated, including fat globule size, zeta potentials and creaming stability and its antioxidant activity in emulsion systems were also studied by peroxide value and $^1H$-NMR spectrum. It was found that fat globules in emulsions with purified surface-active substances were much smaller than ones with the unpurified. In addition, as pH of the emulsion lowered and with increasing NaCl concentration in the emulsion, they were observed to increase, which led to worse creaming stability. These properties were reflected in changes of zeta potentials of emulsions. The oxidative stability was better in emulsions with purified surface-active substances than ones with Tween 20 or commercial lecithin, possibly resulted from the existence of sinapic acid in the extract. It was concluded that purified surface-active substances from defatted rapeseed cake could be simultaneously used as emulsifier and antioxidant agent in emulsion system.

• 한국식품저장유통학회지
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• 제17권4호
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• pp.435-443
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• 2010

Physicochemical and functional properties of collage from skate skin (Raja Kenojei) are examined depending on pH and NaCl concentration in the medium. The solubility decreased as NaCl concentration increased but, turbidity increased as concentration of collagen increased. Oil-holding capacity and water-holding capacity were similar to other fish skin collagens. Emulsion activity, creaming stability, and viscosity were lowest at where pH levels were isoelectric point regions of collagens. However, the higher pH values at 7.0-9.0 caused increasing foam expansion, foam viscosity, and gel strength. These results indicated that collagen from skate skin could be used as a functional ingredient for food and industrial applications.

• Food Science and Biotechnology
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• 제16권6호
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• pp.999-1005
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• 2007

An oil-in-water (O/W) emulsion [20 wt% com oil, 0.5-6.0 wt% fish gelatin (FG), pH 3.0] was produced by high pressure homogenization, and the influence of pH, protein concentration, and homogenization condition on the formation of FG-stabilized emulsions was assessed by measuring particle size distribution, electrical charge, creaming stability, microstructure, and free FG concentration in the emulsions. Optical microscopy indicated that there were some large droplets ($d>10\;{\mu}m$) in all FG-emulsions, nevertheless, the amount of large droplets tended to decrease with increasing FG concentration. More than 90% of FG was present free in the continuous phase of the emulsions. To facilitate droplet disruption and prevent droplet coalescence within the homogenizer, homogenization time was adjusted in O/W emulsions stabilized by 2.0 or 4.0 wt% FG. However, the increase in the number of pass rather promoted droplet coalescence. This study has shown that the FG may have some limited use as a protein emulsifier in O/W emulsions.

• Food Science and Biotechnology
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• 제18권3호
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• pp.610-617
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• 2009

The stability of corn oil-in-water emulsions coated by milk proteins, sodium caseinate (CAS), or whey protein concentrate (WPC), was compared under the environmental stress of pH change. Emulsions were prepared at 0.1 of protein:oil because the majority of droplets were relatively small ($d_{32}=0.34$ and $0.35\;{\mu}m$, $d_{43}=0.65$ and $0.37\;{\mu}m$ for CAS- and WPC-emulsions, respectively) and there was no evidence of depletion flocculation. As the pH of the emulsions was gradually dropped from 7 to 3, there was no significant difference in the electrical charges of the emulsion droplets between the 2 types of emulsions. However, laser diffraction measurements, microscopy measurements, and creaming stability test indicated that WPC-emulsions were more stable to droplet aggregation than CAS-emulsions under the same circumstance of pH change. It implies that factors other than electrostatic repulsion should contribute to the different magnitude of response to pH change.

• KSBB Journal
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• 제7권2호
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• pp.118-125
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• 1992

1.에멀젼형 화장품시료의 오염정도는 P. aeruginosa의 증식을 촉진하는 fatty acids, waxs, oils, steroids 등의 유기물에 의존하였다. 2. 오염의 결과, 물성의 변화로서 화장품시료의 pH가 40일 경과시 7.6에서 6.0으로 변화되었다. P. aeruginosa의 영양원으로서는 상대적으로 낮은 굴절률을 갖는 물질들이 소모되어 화장품시료(물:오일=70:30)의 굴절률이 1.4430에서 1.4530으로 변화 되었다. 3. 오염이 진행되는 동안 화장품시료의 相의 안정서이 파괴되었으며, 약간의 변색, 변취와 함께 creaming 및 응집현상이 나타났다. 4. P. aeruginosa의 최적증식조건인 pH7.0, 온도$20^{\circ}C$에서, 물과 오일의 부피비에 의한 균증식은 70:30, 80:20, 30:70, 90:10, 50:50의 순서로 되었다. 5. 방부살균제를 첨가하여 challenge test를 한 결과, P. aeruginosa의 증식이 억제되었으며 40일 경과시 균수는 방부살균제를 첨가하지 않은 경우 $10^8$개/ml에서 p-hydroxy benzoic acid propyl ester + phosphoric acid buffer solution첨가로 $5{\times}10^3$ 개/ml로 감소되었다. 6. 시험균주인 P. aeruginosa에 대한 항균력은 p-hydroxy benzoic acid propyl ester + phosphoric acid buffer solution>p-hydroxy benzoic acid buthyl ester + acetic acid buffer solution>p-hydroxy benzoic acid methyl ester + phosphoric acid buffer solution>p-hydroxy benzoic acid methyl ester + p-hydroxy benzoic acid propyl ester>p-hydroxy benzoic acid buthyl ester + potassium chloride sodium hydroxide buffer solution>p-hydroxy benzoic acid buthyl ester + p-hydroxy benzoic acid propyl ester>p-hydroxy benzoic acid methyl ester + acetic acid vbuffer solution>acetic acid buffer solution _ potassium chloride sodium hydroxide buffer solution의 순으로 우수하였으며 pH, 농도, 균수등은 양호한 수준을 유지하였다.

• 한국식품조리과학회지
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• 제24권4호
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• pp.473-479
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• 2008

The principal objective of this study was to evaluate the sensory properties and physical characteristics of muffins produced using different fats(butter, grape seed oil) and mixing methods(Creaming method, Foam method, Single-stage method). The muffins weighed between $63.25{\sim}64.50$ g and were $5.77{\sim}6.42$ cm in height. In a texture analyzer test, muffins prepared via the single-stage method with butter evidenced the highest hardness, gumminess, and chewiness values among the five kinds of muffin prepared in these experiments. The springiness value was highest in the muffin prepared via the foam method with grape seed oil. In the sensory evaluation, we detected no significant differences among the muffins in terms of flavor($4.76{\sim}5.24$), taste($4.65{\sim}5.29$), softness ($4.65{\sim}5.41$), and overall acceptability ($4.47{\sim}5.29$). In the chemical composition analysis, moisture and crude protein contents were found to be higher in the control group(p<0.05) than in the muffin prepared via the foam method with grape seed oil(p<0.01). We noted no significant differences among the muffins in terms of crude lipids or crude ash content.

• 약학회지
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• 제41권5호
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• pp.607-614
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• 1997

Flurbiprofen- and flurbiprofen axetil-loaded microemulsions composed of soybean oil, poloxamer 407, glycerine and water were prepared by generator-type homgenizer and ultrasoni c probe system. The particle size of microemulsions was measured by the dynamic light scattering method. The pharmacokinetics and organ distribution of flurbiprofen were investigated after intravenous injection of flurbiprofen solution, flurbiprofen-loaded microemulsion and flurbiprofen axetil-loaded microemulsions equivalent to 10mg/kg of flurbiprofen to rats. Blood samples were collected from the anterior ciliary artery of rats for 24hr, and flurbiprofen in plasma and organs was analyzed by HPLC. Stable microemulsions were prepared. Even though there is a little change in droplet size just after the preparation, no creaming and no separation were occured during the storage period for 6 months at 4, 21, 37 and 45$^{\circ}C$. Pharmacokinetic parameters and organ distribution of flurbiprofen after intravenous injection of flurbiprofen- and flurbiprofen axetil-loaded microemulsions emulsified with poloxamer 407 were not significantly different from those of commercial lipid microemulsion emulsified with lecithin. Therefore, it is concluded that flurbiprofen- and flurbiprofen axetil-loaded microemulsion prepared with poloxamer 407 could be used as a parenteral formulation.

• 동아시아식생활학회지
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• 제7권2호
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• pp.159-165
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• 1997

The primary objective of this study was to learn the effect of various sugar particle size and level on cookie spread, The effect of sugar particle size and level on sugarsnap cookie spread was studied. Three different particle sized sugars; powered sugar, granulated sugar and sanding sugar, were used for the cookie test baking with five different sugar levels; 30, 45, 60, 75 and 90% based on the weight of flour. In mixing process, 5 minutes of creaming time was used for cream making and then the specific gravity of cream was measured on the basis of each different sugar particle size and level. In the result, the specific gravity of cream was influenced by sugar particle size and sugar level. However, the specific gravity of cream had no influence on cookie dough specific gravity. Cookie spread was influenced by sugar particle size and sugar level. Greater cookie spread was obtained by decreasing sugar particle size and increasing sugar level resulted in increased spread. Therefore, selection of suitable sugar particle size and its use level can be factors in controlling spread and imparting desired packaging characteristics.

• 한국안전학회지
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• 제7권3호
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• pp.22-29
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• 1992

Emulsion-type cometics contain many kinds of carbon and energy source i.e., vegetable oil, mineral oil and carbohydrate etc., those can be used as nutrients and caused contamination by microbials. Thereby we have to keep cosmetics from the possibility of contamination by microbials. From this viewpoint, the purpose of this study is to get the data necessary not only to prevent dermatopathia occurred by microbials but also to sustain the quality. In this experiment, we observed how many Staphylococcus aureus were grown in the prepared cosmetics with or without antiseptics so as to prevent contamination. When the contamination proceed, the stability of phase was disturbed and creaming phenomina was happened with some discoloration and bad smell. About 40 days after, the pH was changed from 7.6 to 6.5 and the refractive index of cosmetic raw materials were changed from 1.4415 to 1.4490(water : oil=70:30). By adding antiseptics Into prepared cosmetics, the number of Staphylococcus aureus with challenge test method were decreased to 7$\times$103 cell/ml. For the antibacterial effect against Staphylococcus aureus, p-hydroxy benzoic acid propyl ester in phosphoric acid buffer solution was the best.