• Journal of the Korean Applied Science and Technology
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• v.31 no.4
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• pp.642-652
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• 2014

The synthesis of octenyl succinyl ${\beta}$-gucan (OSA-${\beta}$-glucan) was carried out and its interfacial properties at the oil-water interface and in emulsion systems were investigated. An aqueous ethanol system as a reaction media was used to facilitate the synthesis process; 10% (w/w) ethanol found to be the best as it showed a maximum degree of substitution (DS: 0.0132). FT-IR showed a characteristic absorption spectrum at $1736cm^{-1}$, indicating the esterification of octenyl succinyl groups to ${\beta}$-glucan backbone. As for interfacial tension measurements, it was decreased with increasing concentration of OSA-${\beta}$-glucan in the aqueous phase and when NaCl was added to aqueous OSA-${\beta}$-glucan solution in the range of 0.01 M to 0.1 M and also when pH was raised (pH 3 ~ pH 9). In systems of emulsion stabilized with OSA-${\beta}$-glucan, fat globule size found to decrease with increasing concentration of OSA-${\beta}$-glucan, showing a critical value of about $0.32{\mu}m$ at 0.5 wt%. When the OSA-${\beta}$-glucan emulsions were stored, it was found that fat globule size was increased with storage time and particularly pronounced increase was observed in emulsion with 1% OSA-${\beta}$-glucan, possibly due to depletion flocculation. Results of creaming stability evaluated by light scattering technique showed that it was more stable in emulsions containing smaller fat globule size. Surface load of OSA-${\beta}$-glucan in emulsions increased with increasing concentration of OSA-${\beta}$-glucan, suggesting a multilayer adsorption.

• Journal of Life Science
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• v.21 no.6
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• pp.829-837
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• 2011

The purpose of this study was to investigate the effects of ethanol extracts from red pepper seeds on cholesterol adsorption capacity and UDP-glucuronyl transferase activity. In vitro cholesterol adsorption capacity of 2%, 5% and 10% ethanol extracts from red pepper seed groups were significantly higher than that of the control group. Sprague-Dawley strain male rats weighing $100{\pm}10$ g were randomly assigned to one normal diet N group and experimental groups fed high fat and high cholesterol diet, which were divided into HF (0.0%), HEA (0.1%), HEB (0.2%), and HEC (0.5%) groups according to the amount of ethanol extracts from red pepper seeds added to their basal diet. The body weight gain in the HF group was higher than that in the N group, and those in the HEA, HEB and HEC groups were lower than that in the HF group However, there were no statistically significant differences among the all the groups. The hepatic triglyceride and total cholesterol contents in the N group was significantly lower than that in the HF group, and those in the HEA, HEB and HEC groups were lower than that in the HF group. The hepatic UDP-glucuronyl transferase activity in the N group was lower than that of the HF group and those in the HEA, HEB and HEC groups were lower than that of the HF group. The serum total cholesterol and triglyceride contents of the HF group were significantly higher than that of the N group, and those of the HEA, HEB and HEC groups were lower than that of the HF group. The serum HDL-cholesterol contents in all groups supplemented with the ethanol extracts from red pepper seeds were significantly higher than that of the HF group. The serum LDL-cholesterol contents of the HF group were significantly higher than that of the N group, and those of the HEA, HEB and HEC groups were lower than that of the HF group. The fecal total cholesterol contents were significantly higher in the HF group compared to the N group, and those of the HEB and HEC groups were lower than that of the HF group. The fecal triglyceride contents in the N group was higher than that of the HF group, and those of the HEA, HEB and HEC groups were lower than that of the HF group. This study suggested that the ethanol extracts from red pepper seeds have powerful health benefits by the UDP-glucuronyl transferase activity and lipid metabolism.

• Korean Journal of Food Science and Technology
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• v.43 no.3
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• pp.375-380
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• 2011

This study was performed to investigate cholesterol improvement effects of adding fermented defatted soybean grit (FD) and FD added to 5 or 10% Corchorus olitorius (FDC). Cholesterol adsorption in the FD and FDC group was more than 70%. Apolipoprotein AI and CIII improved in HepG2 cells, and a greater improvement effect was shown in FDC than that in FD. We also investigated the effect of FDC on body lipid metabolism and a high-fat diet for 4 weeks. Rats were divided into control (Con), high-fat (HF), HF treated with 20% FD (HF-FD), and HF treated with 20% FDC (HF-FDC) groups. Plasma total cholesterol and low density lipoprotein-cholesterol concentrations, hepatic total cholesterol, and triglyceride contents were significantly lower in the HF-FDC group than those in the HF group. Additionally, fecal total cholesterol and triglyceride contents increased in rats treated with FDC. Hepatic 3-hydroxy-3-methylglutaryl-coenzyme A reductase activities were significantly lower in the HF-FDC group than those in the HF group.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.10
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• pp.1278-1286
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• 2008

The effect of Tween 20 addition on changes in the stability of methylcellulose (MC) emulsions (1 wt% MC, 10 wt% n-tetradecane, 20 mM bis-tris buffer, pH 7) was investigated by creaming stability and orthokinetic stability measurements. In the case of MC emulsions containing varying amounts of oil (1$\sim$30 wt%) and no Tween 20 added, creaming stability, judged by mean migration velocity of fat globules ($V_m$), was found to depend on droplet size: the larger the droplet size, the worse the stability [$V_m$: 0.326 $\mu$m $min^{-1}$ ($d_{32}$: 0.32 $\mu$m) ${\rightarrow}V_m$: 0.551 $\mu$m $min^{-1}$ ($d_{32}$: 0.53 $\mu$m)]. With Tween 20, creaming stability was found to be worse than the one without Tween 20, except for MC emulsion containing 0.2 wt% Tween 20. In addition, cream stability was the lowest with the lowest concentration of Tween 20 and a tendency to recover with increasing Tween 20 concentration [$V_m$: 0.598 $\mu$m $min^{-1}$ (0.01 wt%)${\rightarrow}V_m$: 0.389 $\mu$m $min^{-1}$ (0.2 wt%)] was found. From viscosity measurement for aqueous bulk phase of MC emulsions, such a change in the creaming stability was found to coincide well with the results of viscosity measurement. Therefore, it was reasonable to say that creaming stability of MC emulsions containing Tween 20 depended on MC concentration in aqueous bulk phase, which was in turn varied by competitive adsorption between MC and Tween 20 at the oil droplet surface. In case of orthokinetic stability, judged by destabilization time ($t_d$), it was found that the addition of Tween 20 resulted in lowered stability with more pronounce tendency at higher concentrations [$t_d$: 160 min (0.03 wt%)${\rightarrow}t_d$: 100 min (0.2 wt%)]. Moreover, combined with previous results, the orthokinetic stability of MC emulsions containing Tween 20 was found to be exponentially proportional to MC load. In conclusion, competitive adsorption between MC and Tween 20 may affect the stability properties of MC emulsion to varying extents, depending on the concentration of Tween 20.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.12
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• pp.1677-1685
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• 2012

The autolysate and hydrolysate of a common squid liver, Todarodes pacificus, were prepared. Autolysis (liver ratio, pH, temperature) and Protamex-treated hydrolysis (pH, temperature, ratio of protease to liver) conditions were optimized by response surface methodology using central composite design for under 1 hr of hydrolysis time. The desirability profile indicated that maximum DH could be achieved at a squid liver of 93.5%, pH 6.4, and $47^{\circ}C$ in autolysis, while that of Protamex-treated hydrolysis did at a Protamex-to-squid liver level of 0.33%, pH 6.0, and $55^{\circ}C$. Three amino acids, proline, cysteine, and methionine, were not detected in the total amino acid composition of the Protamex-treated hydrolysate, while they were detected in the free amino acid composition. Cadmium was $8.32{\pm}0.03$ mg/100 g-powder for raw, $3.56{\pm}0.02$ mg/100 g-powder for the autolysate, and $13.26{\pm}0.04$ mg/100 g powder for the Protamex-treated hydrolysate. The major molecular weight ranged from 1.0 to 1.5 kDa for the autolysate and from 210 to 470 Da for the Protamex-treated hydrolysate. Food functionalities of the autolysate, such as surface hydrolphobicity, emulsion activity index, emulsion stability, water, and fat adsorption, were similar to the Protamex-treated hydrolysate. Both the autolysate and Protamex-hydrolysate showed high inhibitory activities on the angiotensin-I converting enzyme. Cell toxicity against the HepG2 cell line was not detected in the autolysate or the Protamex-treated hydrolysate by 200 ${\mu}g/mL$.

• Food Science and Preservation
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• v.14 no.3
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• pp.276-280
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• 2007

This study investigated the physicochemical properties of traditional Olbyeossal(Korean-style parboiled waxy rice) and other rices(dried cooked rice, germinated brown rice, and waxy brown rice). Olbyeossal had a moisture content of 12.7% a crude fat level of 1.0%, a crude ash content of 0.9%, and a crude protein value of 6.3%. The color values were 58.63(L value), 0.83(a value) and 21.73(b value). The water adsorption index(WAI) of Olbyeossal was 6.2g/g after 40 min steeping at room temperature, which was much higher than the WAI of the other rices. The hardness of Olbyeossal(10.5 kgf) was higher than those of other rices($7.5{\sim}8.9$ kgf). The initial pasting temperatures of Olbyeossal, dried cooked rice(DCR), germinated brown rice(GBR) and waxy brown rice(WBR) were $39.5^{\circ}C,\;43.5^{\circ}C,\;65.0^{\circ}C,\;and\;64.5^{\circ}C$, respectively. The breakdown and total setback viscosities of Olbyeossal(70 B.U., 50 B.U.) and WBR(10 B.U., 30 B.U.) were lower than those of DCR(120 B.U., 275 B.U.) and GBR(142 B.U., 340 B.U.).

• Korean Journal of Fisheries and Aquatic Sciences
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• v.35 no.1
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• pp.97-104
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• 2002

Protein hydrolysate was prepared as a natural flavor stock from the sharp toothed eel (Muraenesox cinereus) mince using com-mercially available proteolytic enzymes, Alcalase, Neutrase, Protamex, and Flavourzyme. A 6 hr hydrolysis of mince, to which water of the equal weight of the mince was added, with $2\%$ (w/w, protein weight) Elavourzyme at $50^{\circ}$ yielded a hydrolysate of the highest acceptability. Removing the access lipid in liquified hydrolysate (not dehydrated) after enzyme hydrolysis, five times repetitive extraction using n-hexane (liquified hydrolysate : n-hexane=4 : 1, v/v) was effective, resulting in less than $1\%$ lipid content of the dehydrated-hydrolysate. The amino acid composition of the hydrolysate (prepared with Flavourzyme) was similar to that of the starting material. Hydrolysis led to an increase in concentration of not only total free amino acid but also free amino acid such as serine, glutamic acid, alanine, and methionine responsible for umami taste, especially up to about 40 times for methionine. Major free amino acids in amount were leucine, phenylalanine, valine, alanine, and isoleucine and they comprised about half of the total free amino acids, Moisture adsorption, fat adsorption, emulsifying capacity, and foaming capacity of the hydrolysate were 870.1 $\pm$ $7.9\%$, 352.0$\pm$ $5.3\%$, 50.3 $\pm$ $1.2\%$, and $87.5\pm$ $2.5\%$, respectively, and solubility was 83$\~$$84\%$ at acid pH range of 2$\~$4.