• YAKHAK HOEJI
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• v.53 no.3
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• pp.114-118
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• 2009

Bioemulsifiers are those chemicals which are produced from microorganisms but which have both hydrophilic and hydrophobic groups. $\alpha$-Glucosidase inhibitor ($\alpha$-GI) produced from Bacillus lentimorbus B-6 (B-6) showed bioemulsifying activity. But $\beta$-glucosidase inhibitor produced from B-6 didn't show emulsifying activity. $\alpha$-GI was purified from supernatant of B-6 grown in minimal culture medium containing glucose and sodium glutamate by Sephadex G-100 column chromatography and isolated from $\beta$-GI by dialysis against water. Toluene was determined as the best substrate for emulsifying activity of $\alpha$-GI. $\alpha$-GI showed thermostability at $100^{\circ}C$ for 15 min, high salt tolerance up to 32% NaCl and wide range of pH-stability at pH $4\sim10$. Emulsifying character of $\alpha$-GI can be useful for the liposome formation for the treatment of diabetes mellitus.

• Korean journal of food and cookery science
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• v.9 no.4
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• pp.278-283
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• 1993

This study was attempted to investigate the effects of enzymatic modification of milk protein with protease on functional properties. The selected functional properties were solubility, emulsifying activity (EA), emulsion stability(ES), foam expansion(FE), and foam stability(FS). These properties were measu-red from pH 3.0 to pH 8.0. The proteases used in this study were iaolated from Meju(fermemted soybean) and had specific activity of 250 units/㎎ protein at pH 7.0, 1600 units of pretense was used for 1gr. of skim milk protein. Skim milk showed 30.5％ degree of hydrolysis for 1 hr. and 36.4% degree of hydrolysis for 3.5 hrs. of protease treatment at pH 7.0. Solubility of native skim milk, control, 1 hr. and 3.5 hrs. groups were 3.37, 3.64, 10.21, 14.34％o at pH 4.0 respcetively. The emulsifying activity of native skim milk, control, 1 hr. and 3.5 hrs. groups were 38.8,42.0,43.0,46.7ft at pH 4.0, respectively. Enzymatic modification resulted in the increase of solubility and emulsifying activity at pH 4.0. However at pH 5.0 emulsifying activity of 1 hr. and 3.5 hr. group were lower than native skim milk and control groups. 1 hr. protease treatment was found to be most effective way of increasing foam expansion at pH 4.0 to 6.0. It was supported that, protease treated skim milk can be used to improve solubility, emulsifying activity, foam expansion at acid pH. meju protease. skim milk, solubility, emulsion, foam.

• Food Science of Animal Resources
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• v.23 no.1
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• pp.63-69
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• 2003

This experiment was carried out to study changes in solubility and emulsifying properties of whey protein. Whey protein hydrolysates were obtained from tryptic hydrolysis of whey protein concentrate at pH 8.0 and 37$^{\circ}C$ for 6 hours. Emulsifying activity of whey protein hydrolysate was highest at 4 hours of hydroysis and at 5.50% of DH. During hydrolysis of whey protein concentrate with trypsin, ${\alpha}$-lactalbumin was not easily broken down. But ${\beta}$-lactoglobulin was hydrolysed rapidly from the early stage of hydrolysis, producing several low molecular weight peptides, which have to participate in increasing emusifying activity. The solulbility of hydyolysates tended to increase depending on hydrolysis time; however, there was a gradual decrease after 5 hours. The hydrolysate had a minimum solubility near the isoelectric point range (pH 4∼5). The more hydrolysed the whey protein concentrates, the more soluble they are near the pl. They aye also more soluble above pH 6. Emulsifying activity of hydrolysates showed similar results to solubility. Creaming stability gradually increased when hydrolysis increased, increasing rapidly above pH 8 after 4 hours of hydrolysis.

• Applied Biological Chemistry
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• v.39 no.4
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• pp.282-286
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• 1996

To effectively utilize fish skin gelatin as a material for quality improvement in surimi gel from fish with a red muscle, conger eel skin gelatin was modified with succinic anhydride, and funtional properties such as emulsifying activity and emulsifying stability were determined. The degree of chemical modification incresed up to 0.3 g of succinic anhydride/g of gelatin, above this adding ratio a nearly constant value was reached. The maximum amount of modification was about 90%. The emulsifying activity and emulsifying stability of gelatin gradually increased up to 89.8% of succinylation extent, little changed above of succinylation extent. The other functional properties as solubility, water holding capacity, foam expansion and foam stability were improved following succinylation with 0.3 g of succinic anhydride/g of gelatin. Amino acid composition of succinylated gelatin was similar to that of unmodified gelatin. Heavy metal contents such as cadmium, lead, copper and zinc of succinylated gelatin were lower than those of unmodified gelatin.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.38 no.2
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• pp.119-131
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• 2012

The W/O emulsion is widely used for cosmetics because of its water-proofing benefit and long-lasting moisturizing effect. However, because of low stability of the W/O emulsion, it is very important to control the concentration of electrolyte and emulsifying agent, and ratio of water phase. Among these factors, we focused on the effects of different structures of emulsifying agents on the change of stability. Emulsifying agents were sorted into polyglyceryl ester, silicone and sugar series. We also examined the emulsifyingability of emulsifier by changing the ratio of normal and silicon oil in the oil phase. Through these experimental results, we figured out the property of w/o emulsion depending on the types of emulsifiers, and observed the stability of emulsion considering the change of particles and viscosity over time.

• Journal of the Korean Society of Food Science and Nutrition
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• v.25 no.1
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• pp.118-122
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• 1996

난황을 이용한 유화식품인 마요네즈 제조시 천연고분자 물질인 chitosan의 사용가능성을 조사하기 위하여 난황의 유화력과 유화 안전성에 미치는 chitosan의 효과와 마요네즈 제조시 chitosan 첨가특성을 조사하였다. Chitosan을 난황 무게에 대해 0.1% 첨가한 결과난항의 유화력은 약 10%증진되었으며 유화 안정성은 뚜렷이 증진되었다. 마요네즈 제시 0.1% chitosan 첨가에 의해 마요네즈의 유화 안정성을 증가되었으며 대조구의 첨가 대두유에 비해 40% 증량 처리구에 있어 유화 안정성 및 점도는 대조구에 비해 우수하였으며 색택은 비슷한 경향을 나타내었다. 마요네즈의 퍼짐서, 점성, 맛, 종합적 기호도에 관한 기호성은 0.1% chitosan 첨가구가 대조구에 비해 양호하였으며, 40% 증량한 경우 더욱 우수하였으며 60% 증량한 겨웅 대조구와 유사하였다.

• Food Science of Animal Resources
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• v.35 no.3
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• pp.315-321
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• 2015

The aim of the present work was to investigate the effect of NaCl concentration on the emulsifying and rheological properties of porcine myofibrillar protein (MF)-stabilized soybean oil and fish oil emulsion (SO-EMs and FO-EMs). Emulsions (EMs) were prepared from 1% MF with 10% SO or FO at various NaCl concentration (0-0.5 M). The emulsifying ability index (EAI) of the EMs increased with increasing NaCl concentration for both oil types. Conversely, increasing NaCl manifested decrease in the emulsion stability index (ESI). In addition, creaming index (CI) also increased with NaCl concentration. From the microscopic observation, droplets of the EMs were more aggregated at relatively higher NaCl concentrations, especially for FO-EMs. All EMs had a gel-like structure owing to G' > G" from the rheological analysis. Comparing the oil types, the emulsifying capacity of SO-EMs was more stable than that of FO-EMs at all NaCl concentrations as determined from the CI value and microscopic observation. Therefore, it can be concluded that SO-EMs and FO-EMs are more stable at relatively lower concentrations of NaCl. In addition, the dispersed stability of SO-EMs was better than that of FO-EMs at the same concentration of NaCl.

• Journal of Life Science
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• v.12 no.6
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• pp.745-751
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• 2002

Several bacterial strains producing biosurfactants were isolated from polluted marine and soil by oil. One of the strains named LSC11 showed strong production activity of biosurfactants. This strain was identified as a Bacillus sp. LSC11 based on the morphological, biochemical, and physiological characteristics. The biosurfactant, produced by the strain, emulsified crude oil, vegetable oil, and hydrocarbons. The surface tension of the culture broth of Bacillus sp. LSC11 decreased to 32 mN/m. The crude biosurfactant was obtained from the culture broth by acid precipitation, freeze drying, solvent extraction, and evaporation. The emulsifying activity of the biosurfactant showed better than the chemically synthesized surfactant (SDS, Span40, Span 85). The biosurfactants had strong properties as an emulsifying agent and as an emulsion-stabilizing agent.

• Journal of the Korean Applied Science and Technology
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• v.18 no.1
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• pp.55-59
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• 2001

These N-acyl amino acid surfactants is normally produced by reaction of acid anhydride with sodium ${\ell}-glutamate$ hydrolysates under Schotten-Baumann condition i.e., in alkaline aqueous medium. To avoid using fatty acid chlorides, acylations were also carried out with the fatty acids themselves or with their methyl esters, but unfortunately these methods cannot be used in practice, dodecenyl succinic anhydride, was to be studied for their suitability as acylating agents the production if acylated glutamine hydrolysates. The surface activities including surface tension forming power, forming stability and emulsifying power were measured. The experimental results revealed that the products have a good emulsifying power. Thus, there derivatives will be expected to be used an emulsifying agent for O/W type cosmetic emulsion.

• Journal of the Korean Applied Science and Technology
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• v.34 no.4
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• pp.1058-1065
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• 2017

Amino acid based surfactants as protein-surfactants is eco-friendly compound. So, amino acid based surfactants is expected as next generation surfactants. Amino acid based surfactants has high biodegradability, low toxicity and surface active properties. In this experiment, amino acid based surfactants, cocoyl glycine, was synthesized by glycine and triglyceride such as coconut oil and palm oil. And it was tested the surface tension, emulsifying properties, foam stability and HLB value. The synthesized surfactants was confirmed by FT-IR. Surface tension of surfactants synthesized by coconut oil on diluted aqueous solutions of surfactants was 31.2 dyne/cm at $1.0{\times}10^{-4}mol/L$. Surface tension of surfactants synthesized by palm oil on the diluted aqueous solutions of surfactants was 42.1 dyne/cm at $3.2{\times}10^{-5}mol/L$. Foam stability measured the foam height as time passed. Initial foam height of surfactants synthesized by coconut oil is 14.5 cm, and 10.7 cm after five minutes. Initial foam height of surfactants synthesized by palm oil is 3.0 cm, and 2.8 cm after five minutes. Foam height of surfactants synthesized by coconut oil was higher than surfactants synthesized by palm oil. But foam stability of surfactants synthesized by palm oil was better than surfactants synthesized by coconut oil. The emulsifying properties of synthesized surfactants are observed in benzene and soybean oil and emulsifying properties in organic solvent is better than in soybean oil.