• Preventive Nutrition and Food Science
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• v.20 no.3
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• pp.183-189
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• 2015

In the present study, an optimum protease was selected to hydrolyze the egg white liquid protein for the antioxidant peptides. Alcalase treatment yielded the highest amount of ${\alpha}$-amino groups (15.27 mg/mL), while the control (no enzymatic hydrolysis) showed the lowest amount of ${\alpha}$-amino groups (1.53 mg/mL). Alcalase also gave the highest degree of hydrolysis (DH) value (43.2%) and was more efficient for egg white liquid hydrolysis than the other enzymes. The Alcalase hydrolysate had the highest radical-scavenging activity (82.5%) at a concentration of 5.0 mg/mL. The conditions for enzymatic hydrolysis of egg white liquid with Alcalase were selected as substrate : water ratio of 2:1. Five percent Alacalse treatment did not show significant (P>0.05) increases of DH and ${\alpha}$-amino nitrogen content after 24 hhydrolysis. Thirty two hour-hydrolysis with 5% Alcalase is sufficient to make antioxidative egg white liquid hydrolysate from egg white liquid. DPPH and ABTS radical-scavenging activities were significantly (P<0.05) higher after enzymatic digestion. These results suggest that active peptides released from egg-white protein are effective radical-scavengers. Thus, this approach may be useful for the preparation of potent antioxidant products.

• Food Science of Animal Resources
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• v.38 no.3
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• pp.442-450
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• 2018

Liquid egg products can be contaminated with Salmonella spp. during processing. A predictive model for the growth of Salmonella spp. in unpasteurized liquid eggs was developed and validated. Liquid whole egg, liquid yolk, and liquid egg white samples were prepared and inoculated with Salmonella mixture (approximately 3 Log CFU/mL) containing five serovars (S. Bareilly, S. Richmond, S. Typhimurium monophasic, S. Enteritidis, and S. Gallinarum). Salmonella growth data at isothermal temperatures (5, 10, 15, 20, 25, 30, 35, and $40^{\circ}C$) was collected by 960 h. The population of Salmonella in liquid whole egg and egg yolk increased at above $10^{\circ}C$, while Salmonella in egg white did not proliferate at all temperature. These results demonstrate that there is a difference in the growth of Salmonella depending on the types of liquid eggs (egg yolk, egg white, liquid whole egg) and storage temperature. To fit the growth data of Salmonella in liquid whole egg and egg yolk, Baranyi model was used as the primary model and the maximum growth rate and lag phase duration for each temperature were determined. A secondary model was developed with maximum growth rate as a function of temperature. The model performance measures, bias factor ($B_f$, 0.96-0.99) and $r^2$ (0.96-0.99) indicated good fit for both primary and secondary models. In conclusion, it is thought that the growth model can be used usefully to predict Salmonella spp. growth in various types of unpasteurized liquid eggs when those are exposed to various temperature and time conditions during the processing.

• The Korean Journal of Food And Nutrition
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• v.30 no.2
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• pp.269-281
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• 2017

In this study, quality characteristics and antioxidative activities were comparatively evaluated between the macaron with egg white powder added at the ratios of 2, 4, 6 and 8% and the macaron with added liquid egg white, in order to determine the applicability of the macaron with added egg white powder. The analysis of amino acids indicated that the group with 8% of egg white powder added showed the highest total amino acid content of 7,584.20 mg/100 g. The group with 4% of egg white powder added showed the highest sweetness (p<0.01); whereas, and the group with 2% of egg white powder added showed the highest pH (p<0.001). In terms of the chromaticity, L (p<0.01) and a values (p<0.05) were increased with the increasing percentage of added egg white powder. With the increasing percentage of added egg white powder, textures such as hardness (p<0.01), chewiness (p<0.05), gumminess (p<0.001), and cohesiveness (p<0.001) decreased; whereas, adhesiveness (p<0.001) and springiness (p<0.01) increased. The results of the sensory evaluation indicated the highest preference for the macaron containing 6% white egg powder, in all items. DPPH free radical scavenging activity, SOD-like activity, and reducing power were increased with increasing amounts of added egg white powder (p<0.001). Collectively, the results indicated that the production of macaron with the addition of 6% of egg white powder is the most suitable mixing ratio for enhancing the preference and quality level.

• KSBB Journal
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• v.22 no.2
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• pp.119-122
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• 2007

Since egg white contains various protein, it is important to research the protein distribution of egg white. Specially, lysozyme and ovalbumin important proteins, are used in medicine and food industry. Reversed phase high performance liquid chromatography has been used for separation of egg white, and column of RP-HPLC is available in variety. We have used C4, C8 and C18 columns to obtain chromatograms by varying carbon chain length of stationary phase. Long carbon chain length of stationary phase has good separation of egg white. Also, we have changed the composition of mobile phase (acetonitrile, water, and trifluoroacetic acid) to find optimum chromatograms. Acetonitrile and water composition of 50 : 50 show many peaks from egg white. Isocartic and gradient elution in RP-HPLC were used to compare the chromatography of egg white.

• Food Science of Animal Resources
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• v.37 no.5
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• pp.646-653
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• 2017

Alcalase hydrolysis of liquid egg white was used to produce 5-hydroxytryptophan (HTP) under various conditions and investigate the sleep-potentiating activity of liquid egg white hydrolysate (LEH) on pentobarbital-induced sleep. Alcalase hydrolysis yielded the highest content of 5-HTP ($13.50{\mu}g/mL$), while neutrase hydrolysis showed the lowest 5-HTP content ($5.23{\mu}g/mL$). The liquid egg white to water ratio (1:1) was optimal for the production of 5-HTP with high amino-nitrogen (A-N) content and degree of hydrolysis. The 5-HTP, amino-nitrogen, and degree of hydrolysis increased until 24 h of hydrolysis and slightly increased thereafter during hydrolysis with 2% and 5% enzyme addition. 5-HTP administration at doses of 6 and 9 mg/kg significantly increased sleep duration and decreased sleep latency time compared to that in the control (p<0.05). LEH (150 mg/mouse), which was equivalent to 5-HTP at 6 mg/kg, significantly decreased sleep latency time and increased sleep duration time compared to that in the control (p<0.05). Oral administration of LEH showed sleep-potentiating effects because of 5-HTP. The sleep-potentiating activity of LEH may have occurred through 5-HTP in our pentobarbital-induced sleep model. LEH may be a valuable alternative to sleep enhancement and may be used as a sleep-potentiating agent.

• Journal of Food Hygiene and Safety
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• v.31 no.5
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• pp.342-348
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• 2016

The objective of this study was to compare the change of S. Enteritidis with S. Typhimurium populations in liquid egg products. S. Enteritidis or S. Typhimurium was inoculated into egg white and egg yolk and stored at 8, 10, 15, 25, and $35^{\circ}C$, respectively. In egg white, no growth of S. Enteritidis and S. Typhimurium was observed at 8, 10, 15, and $35^{\circ}C$, while both S. Enteritidis and S. Typhimurium in egg white stored grew more than 1 log CFU/ml after 50 hours storage at $25^{\circ}C$. In egg yolk, there was no growth of S. Enteritidis and S. Typhimurium at $8^{\circ}C$ but growth of both strains was observed at 10, 15, 25, and $35^{\circ}C$. Since growth of S. Enteritidis and S. Typhimurium was only observed in egg yolk, primary growth models for both strains were developed using modified Gompertz equation and then secondary models for lag time (LT), specific growth rate (SGR), and maximum population density (MPD) were developed as a function of temperature. At all temperatures, more rapid growth of S. Enteritidis than S. Typhimurium was observed in egg yolk, indicating the greater risk of S. Enteritidis than S. Typhimurium in egg products. In conclusion, the results indicate that temperature control less than $8^{\circ}C$ is very important to ensure safety of liquid egg products, especially liquid egg yolk.

• Culinary science and hospitality research
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• v.20 no.1
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• pp.65-75
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• 2014

This study prepared steamed eggs at various ratios of yolk and white in packaged liquid eggs to investigate the quality characteristics of steamed eggs through sensory tests and analyses of water content, color, pH and texture profiles. The results are expected to be used in developing steamed egg products and preparing processed egg dishes. Moisture contents of steamed egg samples increased with increased percentage of egg white. Hunter color values of L(lightness) also increased with increased percentage of egg white, while a(redness) and b(yellowness) decreased. Moreover, pH increased with increased percentage of egg white. Texture profile analyses in hardness, springiness, chewiness, gumminess, and cohesiveness decreased significantly with increased percentage of white, but adhesiveness was not significantly different. As the results of sensory test, yellowness increased with increased percentage of yolk. Roasted nutty smell was highest in the steamed egg sample prepared with 250g yolk and 200g white, and fishy smell increased and boiled egg smell decreased with increased percentage of white. Roasted nutty taste and fishy taste increased with increased percentage of white. In contrast with brittleness, hardness, springiness, and chewiness decreased with increased percentage of egg white. The acceptance score was high in the steamed egg samples prepared with a ratio of egg yolk 250/egg white 200 or egg yolk 150/egg white 300.

• The Korean Journal of Food And Nutrition
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• v.29 no.4
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• pp.449-455
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• 2016

We developed a type of sausage made of chicken breast and liquid egg whites for consumers interested in weight management. To determine the quality of the product, its chemical characteristics, fatty acid composition, free amino acid contents, and nucleotides contents were evaluated during 4 weeks of storage. Sensory evaluation was conducted by both general consumers and body-builders. The sausage was proposed as a fat-free product as fat content was 0.12% based on the Korean Indication Standard of Animal Origin Food. Protein content was 13.42% and calorie value was 61.50 kcal/100 g of the sausage. In sensory evaluation, the mixture of chicken breast and egg whites stuffed into the same casing had an adverse effect on taste, color, texture and overall acceptance while the product that contained egg white stuffed separately into the outer casing enclosing the chicken breast (double layer) improved these attributes. The developed double-layer sausage can last for at least 4 weeks of storage without quality deterioration of flavor-related compounds, such as fatty acids and nucleotides.

• Korean Journal of Poultry Science
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• v.25 no.3
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• pp.119-128
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• 1998

On account of the recent improvement in performance of brown layers, the market share taken by brown layers has increased to about 50% in the world and to almost 100% in Korea. There are several other reasons why the industry has moved from white to brown, such as : brown layers are used to be more robust, more docile and easier to manage ; e brown layers are easier to sex at the hatchery ; brown layers lay less second grade eggs, due to a better shell Quality ; brown eggs seem to be more attractive than white ; and a clear consumer preference, thus a better price per egg. More recently, however, the trend towards brown eggs has been slowing down. The main reasons for this lie in that white layers can still produce an egg at a lower cost and that white eggs have better de-shelling properties, easier candling and higher yolk and solid content of the liquid egg which are benefits for egg processing industry. Although the performance of the brown layers is still improving, there are increasing opinions in the poultry industry that the market portion of white layers should be increased based on the following reasons, such as : shell color has no effect on the nutritive value of eggs ; . brown layers consume more feed ; the percentage of meat spots is significantly higher in brown eggs than in white eggs ; . brown layers are less efficient in the second cycle of production than in the first ; white layers are more resistant to the disease of fowl typhoid. In order to increase the market share of white layers in Korea, it may be needed to enlighten the consumers not to prefer the brown and large eggs and to inform the excellencies of white eggs widely.

• Journal of Applied Tourism Food and Beverage Management and Research
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• v.13 no.2
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• pp.119-127
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• 2002

This study was made to find the compound of it's taste and properties of texture and also it's color desired and optimal conditions when the natural spices garlic, celery, parsley, bay leaves, pepper com, nutmeg, shallot, onion, tarragon, lemon juice-are added to reduction of the spices if the liquid egg yolk and hot virgin olive oil. Extracted by white wine and vinegar and then baked on salamander and gas oven in emulsified properties of sabayon and hot virgin olive oil. It may be indicated the pasteurization that during that in all treatment of the liquid egg yolk was achieved with whisk holding water in double boiling pen 95$^{\circ}C$ for 1min with the object of removing salmonella possibly contained in the yolk. (Imai camd namba e2)