• Korean Journal of Food Science and Technology
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• v.15 no.2
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• pp.123-127
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• 1983

This experiment was carried out to investigate the change in protein of pasteurized whole egg with or without added 1% of sugar during fermentation S. lactis, L. casei and S. faecalis were used in this fermentation test. Whole egg showed no phenomenen of coagulation by heating at $58^{\circ}C$ for 30 min, but the patterns in polyacrylamide gel of pasteurized whole egg without sugar added were changed by fermentation, especially in the egg fermented with L. casei. Polyacrylamide gel electrophoretic patterns of pasteurized whole egg added 1% of sugar changed more significantly by fermentation than pasteurized whole egg without sugar added and the most significant change was observed in the bands of conalbumin, preconalbumin, globulin and postalbumin by S. faecalis.

• Journal of the East Asian Society of Dietary Life
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• v.18 no.1
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• pp.72-79
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• 2008

This study investigated the changes in textural characteristics that occurred by adding maltose syrup, dextrin, and sucrose to whole egg gels, by assessing coagulation after cooling. It also examined the optimal NaCl and sucrose concentrations for whole egg gels sensory evaluations, and then studied how the addition of sucrose effected gel formation and textural characteristics under optimal NaCl concentration. The additions of maltose syrup, dextrin, and sucrose, presented some color changes. The greater the addition of maltose syrup or dextrin, the lower the L, a, and b values of the whole egg gel and whole egg liquid, and ultimately the color turned dark bluish green. With increasing additions of sucrose, maltose syrup, and dextrin, the viscosity of the whole egg liquid increased slightly. In terms of the mechanical texture characteristic of the gel, the texture was most elastic with the 0.8% addition of sucrose, and hardness decreased by increasing the ratio of added sucrose. Increasing amounts of maltose syrup resulted in less hardness and SF. And for dextrin, the SF increased up to 2.5 and then decreased, and hardness decreased with increasing amounts of dextrin. Based on sensory evaluations, the 0.8% addition of NaCl was significantly preferred(p<0.05), in terms of salty taste. The overall preference scores indicated that the whole egg gel made with 0.3% sucrose and the optimal NaCl concentration(0.8%) was most preferred, and each sample was significant(p<0.05). Under the optimal 0.8% NaCl concentration increasing the sucrose concentration resulted in a darker egg gel color, in terms the L value. SF, NF, and hardness, which are mechanical texture parameters, were when 0.8% sucrose and the optimal NaCl concentration of 0.8% were added to whole egg liquid, in preparing the whole egg gel.

• Korean journal of applied entomology
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• v.34 no.2
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• pp.140-146
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• 1995

Changes in protein content during oocyte development was measured and egg-specific protein was characterized from the eggs in Lucilia illustris. During normal development ovarian protein was rapidly increased at 72hr and reached maximum at 96hr after a protein meal, when the eggs were fully matured. Purified protein from the ovaries by gel filtration of DEAE-cellulose an Sephacryl S-200 was loaded on 7.5% native polyacrylamide gel electrophoresis and identified at ${R}_{f}$ 0.4 as egg-specific protein, which has a mol. wt of 110,000. A total of 13 amino acids in th egg-specific protein was identified and expecially asparagine, glutamic acid, and tyrosine were highly concentrated. Five fatty acids were also identified. It is suggested that there is a specific protein in the eggs of L. illustris except yolk protein synthesized and secreted by fat body.

• BMB Reports
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• v.32 no.6
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• pp.579-584
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• 1999

Mantis egg fibrolase (MEF-3) was purified from the egg cases of Tenodera sinensis using ammonium sulfate fractionation, gel filtration on Bio-Gel P-60, DEAE Affi-Gel blue gel affinity chromatogragphy, and MONO-Q anion-exchange chromatography. This protease had a molecular weight of 35,600 Da as determined by SDS-polyacrylamide gel electrophoresis under reducing conditions and its isoelectric point was 6.0. The N-terminal amino acids sequence was Ala-Thr-Gln-Asp-Asp-Ala-Pro-Pro-Gly-Leu-Ala-Arg-Arg. This sequence was 80% homologous to the serine protease from Tritirachium album. MEF-3 readily digested the ${\alpha}$-and ${\beta}$-chains of fibrinogen and more slowly the ${\gamma}$-chains. It showed strong proteolytic and fibrinolytic activities. Phenylmethanesulfonyl fluoride and chymostatin inhibited its proteolytic activity, while EDTA, EGTA, cysteine, ${\beta}$-mercaptoethanol, elastinal, tosyl-lysine chloromethylketone, and tosyl-amido-2-phenylethyl chloromethyl ketone did not affect its proteolytic activity. Among the chromogenic protease substrates, the most sensitive one to the hydrolysis of MEF-3 was benzoyl-Phe-Val-Arg-p-nitroanilide. Based on these experimental results, we speculated that MEF-3 is a serine protease with a strong fibrin(ogen)olytic activity.

• Korean Journal of Poultry Science
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• v.16 no.3
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• pp.157-167
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• 1989

Pretreatment of egg white and ion exchange resins was attempted to separate lysozyme from egg white efficiently. Apparent viscosity of egg white could be decreased to 3cp by homogenization for 30 minutes at 2, 000rpm and ultrasonication for 45 minutes. The result of testing adsorption capacity of lysozyme was as follows； CM-Sephadex C-25 ＞Duolite C464＞Amberlite C-50＞Dowex MSC-1＞Amberlite IRC-50＞Amberlite IRC-84. Although CM-Sephadex C-25 showed highest adsorption capacity of lysozyme, egg white could not eluted easily. Duolite Cf64 was selected based on relatively high lysozyme adsorption and good egg white eluting property for separation of egg white lysozyme. Na$^{＋}$ form of Duolite C-464 was most effective on adsorption of Iysozyme. To separate lysozyme from egg white efficiently rinse buffer and eluting solution were selected 0.1M sodium phosphate buffer at pH 6.5 and 10% ammonium sulfate respectively. After separating lysozyme from egg white, foaming power of egg white was decreased to 85.3%. Color of egg white gel was not changed while hardness of egg white gel was decreased by 30% after separating lysozyme. However, elasticity of egg white gel was increased by 13% in lysozyme-separated egg white.

• Journal of the Korean Home Economics Association
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• v.17 no.4
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• pp.35-42
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• 1979

The effects of salt concentration on the qualities of cooked egg preparations were evaluated. Diluted egg samples which contained different amounts of slat were prepared by diluting whole egg fluid with rice washing, anchovy stock , or distilled water. After heating them rapidly, hardness, gel strength, and amount of syneresis were determined along with the performance of sensory test. the pH of the diluted eggs also measured before heating. Results obtained from these experiments are summarized in the following. 1. The pH of whole egg, egg yolk, and egg white was 7.32, 6.31, and 8.41 , respectively. 2. The pH whole eggs after addition of diluting solutions and salt showed a little differences over the whole salt concentration as follows. distilled water dilution > anchovy stock dilution > rice washing dilution 3. The hardness and gel strength of cooked samples were increased with the increase of salt concentration in the range of low salt concentrations of all diluting solution. These physical properties marked maximal values at salt concentration of 3% and then decreased as salt concentration increased. 4. Amount of syneresis decreased as salt concentration increased regardless of all diluting solutions used. 5. In sensory test, 1% salt concentration were scored good by the panel members regardless of diluting solutions which showed no significant difference among three diluting solutions.

• Food Science and Biotechnology
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• v.15 no.3
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• pp.418-423
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• 2006

Egg white powders (EWPs) were produced after pH adjustment (PH 6-9) of fresh egg white, followed by spray-drying, and foaming and gelling properties of EWPs were examined. EWP produced after pH adjustment to 6.5 (EWP-6.5) resulted in significantly higher foaming ability and gel hardness than control and other pH-adjusted EWP. Significant increases in surface -SH content and surface hydrophobicity of EWP-6.5 coincided with improved foaming ability and gel hardness. Significantly higher consistency index for reconstituted EWP-6.5 indicates unfolding of egg white protein was substantially increased in EWP-6.5. Decreased a-helix content in EWP-6.5 was confirmed by circular dichroism spectral analysis. These results indicate pH adjustment prior to spray-drying leads to structural changes in egg white proteins, significantly affecting major functionalities of EWP.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.7
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• pp.980-985
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• 2000

Influences of Japanese green tea powder (GTP) supplementation to commercial diet on laying performance and egg quality were studied by using 60 laying hens. The experimental diet with or without 0.6% GTP was given ad libitum to the birds during the period from 6 to 71 weeks of age. The birds started egg production from 21 wk of age regardless GTP feeding. Body weight, feed intake, egg weight tended to decrease with GTP supplementation, while egg production rate tended to increase. Haugh unit score was significantly increased with GTP, which accompanied with the increased albumen height. These were observed almost throughout the laying period over 50 wk. Gel proportion in thick albumen was decreased as storage time is prolonged, then higher values of the gel proportion were recorded in the eggs from GTP group. Thick albumen of the eggs from GTP-fed layers had more carbohydrate than that from control layers. All these indicate physical stability of thick albumen in the eggs from GTP group. Thiobarbituric acid content of egg yolk tended to remain lower in the eggs from GTP group during 5-10 days of storage at room temperature. Levels of egg yolk cholesterol and yolk lipid were significantly reduced by GTP feeding. There were no significant differences in eggshell weight, shell thickness and shell strength between the two groups. Thyroid gland and liver from hens slaughtered at 71 wk of age did not differ in weight irrespective of GTP feeding. The present results suggest that GTP could modify components of edible part of egg, leading to the characteristics favourable to consumers such as high durability of thick albumen and less cholesterol in yolk, without altering general performance of the layers throughout this year round experiment.

• Preventive Nutrition and Food Science
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• v.7 no.4
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• pp.373-377
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• 2002

Allergens in processed foods may place persons with food allergies at significant risk when the labels do not Provide sufficient warnings or identification of high-risk ingredients. Because egg proteins are common food allergens, this study was carried out to identify hen's egg albumin (ovalbumin, OVA) in five commercially processed foods containing egg (custayd, cookie and pasta), and chicken meat (sausage and meatball) by immunological methods using commercially produced murine monoclonal immunoglobulin G (M-IgG), immunoblotting and enzyme linked immunosorbent assay (ELISA). Sample buffer with chelating and reducing agents was prepared and used for the preparation of the protein fractions from the foods. Most bands in sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) profile (5~15% gradient gel) presented at 75 kDa below. OVA (43 kDa) in the sample lanes could not be visually observed on the gel. However, OVA in solutions prepared from custard and cookie could be detected by M-IgG, but were not detected in sausage and pasta. OVA in all samples could be quantitatively determined by the equation obtained from the standard curve by ELISA. Cookie and custard containing egg white and egg, respectively, contained very high concentrations of OVA. OVA in the other products were present in relatively low concentrations, but sufficiently high to pose possible risk of allergy, ELISA is a very sensitive and precise method for the identification and quantification of allergens in food products including allergy-inducible materials.

• The Journal of the Acoustical Society of Korea
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• v.21 no.3E
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• pp.126-131
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• 2002

Ultrasonic measurements are made in egg white to study the properties of the solution of the natural protein. The high-Q ultrasonic resonator method is used to get the ultrasonic absorption spectra over the range 0.2-10 ㎒ at 20℃. It is proportional to the 1.25th power of the frequency. The gelation process caused by heat is studied from the change in the velocity and the absorption. at 3 ㎒ using the pulse echo overlap technique over the range of 10-80℃. The absorption decreases with increasing temperature up to 60℃ where it turns up sharply and rapidly increases thereafter. The strong absorption in the gel region is described by the interaction between the solution and the network structure made of protein. Very slow variation in time elapse is observed after the temperature is quickly raised. It would be a real-time observation of the network building process and the characteristic time for the process is shown to be 400 min. A hysteresis phenomenon with respect to the temperature is observed. This phenomenon is associated with the memorizing effect of the network structure of protein of the gel.