• Food Science of Animal Resources
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• v.33 no.5
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• pp.672-677
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• 2013

The aim of this study was to develop sample preparation method and evaluate the exact cholesterol content in egg and egg powder purchased from Korean markets, and to determine whether significant differences exist among various egg products, since a variety of products are available in Korean markets and there are no recent databases for cholesterol. To evaluate the cholesterol content in chicken egg sold in Korean local market, a simple method using non-heated saponification to determine cholesterol for emulsified foods was applied. The results of recovery for egg and egg powder were in a range of 92.4-105.0%, with a relative standard deviation between 1.1% and 2.8% by using gas chromatography-flame ionization detector. Therefore, the total cholesterol content in whole egg was estimated between 160.8 and 226.3 mg/egg (AV(average) $186.8{\pm}3.5$), which is similar or lower than previously reported levels. The value for cholesterol in egg powder was estimated between 2.94 and 3.49 mg/g (AV $3.23{\pm}0.15$). We suggested method that can be applicable to chicken egg and egg powder matrix as providing rapid and accurate determination of cholesterol in egg and egg powder. This information will be helpful for processed food producers for deciding food labels of cholesterol content.

• Korean journal of food and cookery science
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• v.32 no.5
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• pp.619-626
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• 2016

Purpose: This study aims to provide important methods to increase egg usage eggs in communal food services, based on the knowledge and awareness of the dietician. Methods: A survey on 200 dieticians in various aspects, such as egg purchase, utility, importance of egg dishes and allergy awareness was conducted. Result: Dieticians' highest consideration in purchasing eggs were cost (41.5%) and food safety certification (41.0%); the 88.6% of purchases were general egg. The most inconvenient issues in the purchase were inability to confirm freshness (42.0%), frequent breakage (23.5%) and inconvenience in shell disposal (18.5%). During the process of cooking, cracking egg shells (49.5%) and disposal of shells (14.0%) were marked as the major inconveniences. When questioned on intention to purchase liquid and powder eggs to overcome the shell disposal inconvenience, 64% answered no, with distrust in food safety (44.5%) being the major concern. The frequency of using eggs as the main ingredient was 1~2 times per week, with 49.0%. Food service customers favored rolled omelet (36.7%) and steamed egg (20.6%), and the most used utensil was the frying pan (56.5%). When important factors in egg dishes, namely diverse menu, taste, nutrition, consumer satisfaction and allergic reaction were surveyed, most answered that all 5 factors were important. Conclusion: For increasing egg dish inclusions in communal food service, the safety assurance, increase in liquid and processed egg use, and supply of cooking utilities are necessary.

• Korean Journal of Poultry Science
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• v.27 no.1
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• pp.7-12
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• 2000

An experiment was conducted to investigate the effects of feeding fermented food waste on the egg production and egg qualities in laying hens. A lot of 30 commercial layer(ISA Brown) at the age 58 weeks were placed in individual of 80% commercial feed and 20% fermented food waste(C80%+F20%), a mixture of 50% commercial feed and 50% fermented food waste (C50%+F50%), and a mixture of 20% commercial feed and 80% fermented food waste (C20%+F80%). Daily measurements were made on feed intake, egg production rate, egg weight, yolk color, Haugh unit, shell color during the experimental period. At the end of the experiment, body weight change and egg cholesterol contents were determined. The results indicate that up to 50% of basal diet could be supplied by fermented food waste with little depression in feed intake and efficiency in egg production (p＜0.01). Egg weight, egg shell thickness and Haugh units were not significant different between the treatments and the control. Egg color quality improved with increasing the proportion of the fermented food waste in the diet.

• Journal of the FoodService Safety
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• v.2 no.1
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• pp.30-35
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• 2021

This study was conducted to understand the perception and the usage pattern of egg dishes in university students. The questionnaires were collected from 200 university students residing in Seoul. The age group was 118 (59.0%) in 20s, 50 (25.0%) in 30s, and 32 (16.5%) in 40s and older. Also, 179 (89.5%) were undergraduate students and 21 (10.5%) were graduates. The result of food preferences in the overall survey was as follows: Meats and Poultry (4.46±1.03) > Seafoods (2.92±1.41) > Fruits (2.91±1.17) > Eggs (2.50±1.10) > Vegetables (2.21±1.17). The preference of foods using eggs as the main ingredient was as follows: Rolled egg (4.07±0.81) > Steamed egg (4.05±0.91) > Scrambled egg (3.83±1.03) > Rice omelet (3.77±1.03). The preference of foods using eggs as sub-ingredient was Egg in Ramyeon (4.11±1.08) > Fried egg over Bibimbob (3.87±0.91) > Sliced boiled egg in Naengmyeon (3.78±1.11). The preference of eggs as desserts was Egg tart (4.01±1.08) > Sponge cake (3.72±1.09) > Egg bread (3.63±1.13). The result of the frequency of eating eggs indicating that approximately two-thirds of university students consumed eggs more than 3 times a week. Although there was no significant difference, male students not only consumed eggs more frequently than female students, but also consumed a higher amount. In recent years, since one-person household in college students tends to increase, it is more important to save cooking time and food quality. Thus, the development and dissemination of various egg recipes should be prioritized for university students.

• 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.

• Journal of the Korean Society of Food Culture
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• v.28 no.6
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• pp.603-622
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• 2013

Egg is a food that has been loved from ancient times by people all around the world. It has been called a present from god because its rounded shape was believed to refer to the earth. We found the oldest and most perfectly preserved egg fossil at Chunmachong (天馬) in Kyungju (慶州). We believe that it was used during the period of the Three States or the unified Silla (新羅), and, accordingly, it was a noble food that has been found at the king's grave of the age. Egg, which is called egg of chicken in Korean, was written as egg of chicken (鷄卵), son of chicken (鷄子), bird's egg of chicken (鷄蛋), and round thing of chicken (鷄丸) in the Korean alphabet and Chinese characters. The ancient countries had the following myths about eggs In myths about offspring by egg, they were born as heaven's will to make them god. There were 19 proverbs: 'Hitting a rock with an egg', 'It's like the yellow part of an egg' and 'Even an egg stops when it rolls', etc. According to a theory of divination based on topography, people use eggs when they find a good place. There are 10 proverbs (四字 成語): Dongjiipran (冬至立卵), Nanyeoseoktu (卵與石投) etc. Studies for analysis of egg recipes found in the old literature (cooking, agriculture and fishing, and medical books) in the Chosun Dynasty recorded 36 times where cuisine with egg was mentioned as the main ingredient, 154 times as a sub-ingredient, 79 times as a garnish, and 20 times etc. As a garnish, they were 'finely sliced', 'thin rectangular and the rhombus form', and 'rounded shape'; after grilling they were divided into yellow and white parts. When cooked, they were used in comparison of the size or shape of an object with that of other objects.

• Food Science and Biotechnology
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• v.14 no.6
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• pp.793-797
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• 2005

Optimum conditions for cholesterol removal in egg yolk were evaluated based on ratio of egg yolk-to-water, crosslinked ${\beta}$-cyclodextrin (${\beta}$-CD) concentration, and mixing temperature, time, and speed by adding crosslinked ${\beta}$-CD treated with adipic acid. Cholesterol removal in egg yolk-water mixture increased with increasing ${\beta}$-CD level (10-25%). About 95% was removed by 25% ${\beta}$-CD at 1:1 ratio of egg yolk-to-water and 800 rpm mixing at $40^{\circ}C$ for 30 min. In recycling study, removal rates were measured using ten times recycled crosslinked ${\beta}$-CD in egg yolk, and 85% cholesterol removal was observed with eight times reuse. These results indicated that over 90% cholesterol was removed at 1:1 ratio of egg yolk-to-water, 20% crosslinked ${\beta}$-CD addition, and 30 min mixing with 600 rpm at $40^{\circ}C$.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.7
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• pp.853-859
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• 2006

This study was carried out to investigate the effect of egg shell calcium salt types and egg shell membrane on calcium metabolism in rats. Sprague-Dawley male rats, 4 weeks of age, were fed on free-calcium diets for 2 weeks after adjustment period. Rats weighing approximately $247{\pm}2.3g$ were divided into 6 groups and were fed on the experimental diets containing 0.2% calcium for 4 weeks. Experimental groups were as follows; {ES(M+)} (egg shell powder diet with egg shell membrane), {ES(M-)} (egg shell powder diet without egg shell membrane), {AC(M+)} (egg shell calcium acetate diet with egg shell membrance), {AC(M-)} (egg shell calcium acetate diet without eg shell membrane), {GC(M+)} (egg shell calcium glucuronate diet with egg shell membrane) and {GC(M-)} (egg shell calcium glucuronate diet without egg shell membrane). Bone length of femur was significantly different by the types (p<0.05) of egg shell calcium salts. Bone mineral density of femur showed the highest level in AC(M-) group. Calcium content of femur and calcium absorption rate were higher in egg shell calcium salt groups than in eg shell powder groups. Calcium absorption rate and retention were significantly different (p<0.05) among the types of eg shell calcium salts and were higher in the AC(M-) group than in the other groups. Alkaline phosphatase activity, parathyroid hormone and osteocalcin levels of serum showed no significant difference among the experimental groups. From the above results, it is concluded that bioavailability of calcium is higher in groups of egg shell calcium salts compared to those in egg shell powder, even though egg shell membrane has no effect on calcium metabolism. Thus, these findings suggest the possibility of using egg shell calcium salts as a functional food material related to calcium metabolism.

• Journal of Ecology and Environment
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• v.36 no.1
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• pp.11-17
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• 2013

The life cycle of butterflies is closely related to the growth of food plants and, through a prolonged coevolutionary process, has undergone an ecological adaptation. So, it is important that control the egg-laying number and place to secure enough food plant by female adult to guarantee the survival of the larvae. To study whether oviposition control of the Luehdorfia puziloi takes into greater consideration food plant leaf biomass or leaf abundance, correlation among the egg cluster size, the leaf size, and the number of leaves around egg clusters was investigated. According to the results, the egg clusters size exhibited positive correlation with the leaf size of food plants on which eggs had been laid but did not do so with the number of surrounding leaves. In addition, the number of egg clusters laid exhibited positive correlation with the number of surrounding food plant leaves but not with the leaf size on which eggs had been laid. Consequently, for the Luehdorfia puziloi, the females' recognition of the leaf size seems to be the most important factor in the egg cluster size, and the number of egg clusters had positive correlation with food plant density per unit area.

• Food Quality and Culture
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• v.1 no.1
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• pp.6-12
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• 2007

In this study, we examined the effects of egg yolk powder added to flour dough on the lipid oxidation of fried products during storage. The flour dough containing the egg yolk powder (0, 5, and 10%) was fried in sunflower oil at $180^{\circ}C$ for 90 sec. The fried products were then stored at $60^{\circ}C$ for 9 days in the dark. The lipid oxidation of the fried products was evaluated by fatty acid composition, peroxide values (POV), conjugated dienoic acid (CDA) contents, and thiobarbituric acid (TBA) values. The color and phospholipids (PL) contents of the fried products were also determined by colorimetry and high performance liquid chromatography, respectively. The addition of egg yolk powder to the dough decreased the POV, CDA contents, and TBA values of the fried products during storage. Although POV, CDA contents, and TBA values significantly increased in the products without egg yolk powder during storage, little change was observed in the products with egg yolk powder. The PL contents remained relatively constant in the flied products added with egg yolk powder during storage. The lightness and greenness of the fried products decreased, and the yellowness increased, as the storage time increased. The results clearly indicate that the addition of egg yolk powder to the dough improved the lipid oxidative stability of the fried products during storage in the dark, and the PL in the egg yolk might have contributed to the improvements in lipid oxidative stability.