• Korean Journal of Fisheries and Aquatic Sciences
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• v.34 no.4
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• pp.320-326
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• 2001

To obtain the basic data for preparing edible or biodegradable film, fish meal protein isolates (FMPI) were prepared through alkaline extraction. And FMPI's properties and the ester compounds permeability of FMPI film were measured. FMPI were extracted under various extracting time with 0.2 N NaOH solution at $60^{\circ}C$, Recovery ratios of FMPI extracted from fish meal were increased with extracting time increasing. Surface hydrophobicity of FMPI extracted for 1 hr showed highest value. Emulsifying activity index (EAI) was increased with the increasement of extracting time but its emulsifying stability index (ESI) showed an inverse results. Viscosity of FMPI solution showed the highest value at pH 2 but showed the lowest value at pH 4, The higher concentration of sorbitol as plasticizer showed the higher ethyl acetate permeability of FMPI film, Ethyl acetate permeability of FMPI films according to kind of plasticizers showed different degree and increased in order as follow: polyethylene glycol, glycerol and sorbitol. Ester compounds having the lower molecular weight showed the higher permeability. Increment of temperature increased the ethyl acetate permeability of FMPI film. FMPI haying higher surface hydrophobicity made FMPI film be higher tensile strength. On elongation of FMPI films, kinds of plasticizer were more effective than surface hydrophobicity of FMPI.

• Journal of the Korean Society of Food Science and Nutrition
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• v.12 no.3
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• pp.251-258
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• 1983

This experiment was carried out to investigate the capability of production of artificial milk for leaf protein concentrate (LPC). Chloroplastic protein and cytoplasmic protein were extracted from leaves of Dystaenia takeshimana Nakai and LPC was extracted from leaves of Italian ryegrass to increase the functional properties of LPC as a level of milk casein. One gram of chloroplastic protein and cytoplasmic protein and 1g of LPC were succinylated by addition of succinic anhydride 0.1, 0.25, and 1g respectively. Their functional properties were investigated in this experiment. The results obtained were summarized as follows: 1. The non-succinylated LPC showed a higher value in bulk density than the chloroplastic protein, the cytoplasmic protein and LPC succinylated by addition of succinic anhydride 0.1, 0.25, and 1g respectively. Nevertheless, succinylation had an enhancing effect as indicated by the rises as the degrees of succinylation was increased. 2. Although solubility of non-succinylated LPC was lower than that of milk casein, succinylation caused an effective increase in the solubility of the protein and LPC. 3. Water absorption and fat absorption of succinylated LPC were twice to eight times higher than those of milk casein. Fat absorption was not influenced to the extent by succinylation as the water absorption. Excessive succinylation resulted in the decrease of both water absorption and fat absorption. 4. Emulsifying activity and emulsion stability were increased in proportion to the succinylated degree of LPC. More than 10% increase in the amount of succinic anhydride resulted in an apparent increase in emulsifying activity and emulsion stability. Besides, the succinylated LPC showed more excellent functional properties in emulsifying activity and emulsion stability than milk.

• Journal of the Korean Applied Science and Technology
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• v.16 no.2
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• pp.147-153
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• 1999

As main components of antifoamers, we were used fatty alcohols, fatty acid and fatty acid esters. Then the antifoaming properties on the particle size distribution, temperature and concentration for antifoamers was measured by Air Injection Method of ASTM under 1L/min air flow rate condition, and was measured surface tensions and emulsifying power of antifoamers. The antifoaming properties on the particle size distribution of antifoamers showed excellent antifoaming properties in the range of emulsion particle size from 5.5 to 6.8${\mu}m$. Surface tensions on the $10^{-2}$wt% aqueous solution of antifoamers was $33{\sim}34$ mN/m. And emulsifying power of fatty alcohol antifoamers showed good.

• Korean journal of food and cookery science
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• v.16 no.2
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• pp.151-159
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• 2000

The effects of bromelain and $\alpha$-chymotrypsin treatments on the functional properties(foaming capacity, foaming stability, emulsifying capacity, and emulsifying stability) of soy protein isolate(SPI) and the addition of various sweeteners(sucrose, sorbitol, xylitol) on the quality attributes(viscosity, overrun ratio, melt-down property, and sensory characteristic) of soy ice cream were studied. SPI was more effectively hydrolyzed with $\alpha$-chymotrypsin than bromelain, resulting in a better foaming and emulsifying capacity. Adding xylitol could significantly improve the viscosity, overrun and melt-down property of soy ice creams while the effect was the lowest in the sucrose addition. Bromelain treatment caused a lower apparent viscosity of SPI suspension compared with $\alpha$-chymotrypsin treatment and untreated. The overrun ratios of the soy ice cream prepared with bromelain and $\alpha$-chymotrypsin treated SPI were 18.9∼25.9% and 24.9∼40.3%, respectively as a result of freezing with agitation for 20 min in an ice cream maker. Comparatively, untreated SPI could bring only 15.8∼21.4% overrun ratios after operating for 15 min. The bromelain treatment caused high melt-down tendency of the product while soy ice cream with untreated SPI showed an opposite trend. In sensory characteristics, no significant differences in the strength of beany flavor were noted among the samples. Sweetness, bitter taste, icy feel, and mouthfeel of the product were greatly affected by the enzyme-treatment of SPI. Soy ice cream added with xylitol after $\alpha$-chymotrypsin treatment was the most acceptable among all samples.

• Journal of Life Science
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• v.14 no.2
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• pp.320-324
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• 2004

The objective of this study was investigate the characteristic of biosurfactant produced from the isolated strain. The strain was isolated from soil samples and identified as Bacillus sp. TBM 911-5 by physiological characteristics and the partial nucleotide sequence analysis of 16S rDNA. We measured the surface tension every 6 hours for 80 hours. The surface tension of the culture filtrate of Bacillus sp. TBM 911-5 was decreased to 29 mN/m. Biosurfactant concentration was determined by diluting the culture filtrate until the critical micelle concentration (CMC). The biosurfactant emulsified hydrocarbons, vegetable oil and crude oil. Using soybean oil as substrate, the maximum emulsification activity and stability was obtained from the biosurfactant. The biosurfactant produced from Bacillus sp. TBM 911-5 had strong properties as an emulsifying agent and an emulsion-stabilizing agent.

• Korean Journal of Food Science and Technology
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• v.23 no.1
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• pp.25-30
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• 1991

Chicken liver was enzymatically hydrolyzed with an alkaline protease and determined the optimal conditions of reaction temperature and time, pH and enzyme to substrate ratio(E/S ratio) for possible utilization as a protein supplementary ingredient. The functional properties of hydolysate measured were water and oil absorption capacity, emulsifying activity and viscosity and sensory properties were also evaluated. It was found that hydrolysis at $60^{\circ}C$ and pH 8.0 were most effective and the degree of hydrolysis increased with increasing E/S ratio. A decrease in water and oil absorption capacity and an increase in viscosity were found during hydrolysis. The lowest emulsifying activity and highest water absorption were measured for 1/2 hour-hydrolysate and little difference was found for those treated more than 1 hour. The sensory characteristics of odor showed no significant difference among the chicken liver hydrolysates while the brightness increased and red decreased significantly(p<0.01) as the hydrolysis proceeded.

• Journal of the Korean Applied Science and Technology
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• v.15 no.2
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• pp.77-81
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• 1998

Surface active properties of these aqueous Gemini surfactant solutions including surface tension, critical micelle concentration(cmc), foaming power, foam stability, emulsifying power and Krafft point were measured at given conditions. They showed excellent properties, being compared with conventional single-chain surfactants such as sodium dodecyl sulfonate(SDS). Their surface tensions in the aqueous solutions were decreased to $30{\sim}38$ mN/m, which is lower than 39 mN/m of SDS, and their cmc values evaluated by surface tension method were $2.8{\times}10^{-5}{\sim}3.3{\times}10^{-4}$ mol/L. These values were also much lower than that of SDS, $9.8{\times}10^{-3}$ mol/L. The foaming power and foam stability, especially decyl and dodecyl compounds, were good and the emulsifying power in benzene or soybean oil was also excellent. All of the synthesized Gemini surfactants possessed good water solubility and their Krafft points were all below $0^{\circ}C$. As results, DDED and DDOD, Gemini surfactants which were synthesized are expected to be applied as foamers, emulsifiers and so on.

• Journal of the Korean Applied Science and Technology
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• v.30 no.4
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• pp.779-789
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• 2013

This study aimed to investigate the emulsifying properties of bovine lactoferrin in food emulsion system. First, lactoferrin solution was prepared to study its surface activities, such as surface adsorption characteristics and ${\zeta}$-potential. Second, some physicochemical properties of lactoferrin emulsion which resulted from variations of environmental conditions (i.e., pH or NaCl addition) were determined. As for surface adsorption characteristics evaluated by surface tension, it was decreased with increasing lactoferrin concentration in solution ($1{\times}10^{-5}{\rightarrow}0.2wt%$) and showed a plateau (${\fallingdotseq}44$mN/m) above 0.01 wt%. It was also changed with pH and the minimum value of 53.8 mM/m was observed at pI of lactoferrin. This was related to changes in ${\zeta}$-potential of the lactoferrin solution with respect to pH. Fat globule size of lactoferrin emulsion was decreased with increasing lactoferrin concentration and a stable emulsion was formed above 0.5 wt% lactoferrin in emulsion with fat globule size $d_{32}$ of ca. 0.33 ${\mu}m$ as confirmed by creaming stability experiment (i.e., Turbiscan). As with surface tension, fat globule size of lactoferrin emulsion also changed with pH and showed a maximum value at pI. As evaluated by Turbiscan, in the presence of NaCl, the lactoferrin emulsion showed instability in particular above 10 mM.

• Applied Chemistry for Engineering
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• v.5 no.1
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• pp.99-104
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• 1994

Nonionic surfactants, monoglyceryl pyroglutamates, have been synthesized in a high yield by esterification of monoglyceride with pyroglutamic acid in the presence of sodium acetate catalyst. Their structures were confirmed by IR and $^1H-NMR$ studies. For these compounds surface active properties including interfacial tension and emulsifying power were measured. The interfacial tensions of their oil solution against water were decreased to 5~9dyne/cm and hydrophobic alkyl chain of monoglyceryl pyroglutamates. The experimental results indicated that emulsifying power of the nonionic surfactant was better in benzene than in soybean oil. Due to the good surface properties, the nonionic sutfactants, monoglyceryl pyroglutamates, are expected to be used as emulsifiers.

• Korean journal of food and cookery science
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• v.3 no.2
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• pp.1-8
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• 1987

Eighty eight percent of succinylation at $\varepsilon$-amino group of lysine was obtained from silkworm larvae protein concentrate and it resulted in increased bulk density and fat absorption, improved flavor and color, increased solubility over fivefold. Both emulsifying activity and emulsion stability of the succinylated protein were improved by 30% and emulsifying capacity was enhanced by 4%. Foaming capacity of the succinylated Protein concentrate was improved by 30% and foaming stability improved fivefold. The viscosity of succinylated silkworm larvae protein concentrate was increased at all concentrations and reached the highest at 4~5% of concentations. Acetylation of silkworm larvae protein concentrate caused negligible change in the functional properties studied. Therefore, high emulsification properties of silkworm larvae protein concentrate would be a good protein source for the emulsified foods.