• 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.

• Asian-Australasian Journal of Animal Sciences
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• v.22 no.3
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• pp.421-427
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• 2009

A mixture of three dietary medicinal herb extracts (MHE, mulberry leaf:Japanese honeysuckle:goldthread = 48.5: 48.5:3.0) was prepared as an additive of hen's feed. One hundred-eight, 28-wk-old Lohmann Brown hens were assigned randomly with three levels of MHE in the diet (0, 0.3, and 1%). Hens were fed for 6 wks and eggs were collected in the 6th week, and stored at $4^{\circ}C$ for 14 days to investigate the effect of MHE on the quality and oxidative stability of eggs. Internal quality of the egg including weight, shell color, albumen height, yolk color, shell weight, shell thickness, and Haugh units was not different among the dietary treatments. The oxidation stability of raw and cooked egg was determined by 2-thiobarbituric acid reactive substances (TBARS) value, 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity and 2,2'-azinobis(3-ethylbenzonthianoline-6-sulfonic acid) ($ABTS^{+}$) radical reducing ability. Results indicated that TBARS value at day 0 and $ABTS^{+}$ radical reducing ability of eggs from hens fed MHE were higher than from the control group. However, DPPH radical scavenging activity showed no difference in both raw and cooked samples. Results of the present study indicate that dietary MHE may slightly enhance the oxidative stability of eggs.

• Journal of the East Asian Society of Dietary Life
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• v.27 no.1
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• pp.78-87
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• 2017

The objective of this study was to investigate the effects of various washing waters on the quality and safety characteristics of eggs during storage. Eggs were washed with tap water, 100 ppm of sodium hypochlorite, or 30 ppm of slightly acidic electrolyzed water and stored at $10^{\circ}C$ and $20^{\circ}C$. Effects of various washing waters on reduction of Salmonella Enteritidis and aerobic plate counts and survival of S. Enteritidis on egg shells were also analyzed at $10^{\circ}C$ and $20^{\circ}C$ for 25 days. As an index of quality, haugh unit, weight reduction, and pHs of egg white and egg yolk were measured. Reduction percentages of haugh unit and weight were higher at $20^{\circ}C$ than at $10^{\circ}C$. Egg qualities were less affected by tap water, slightly acidic electrolyzed water, and sodium hypochlorite, regardless of storage temperature. The greatest reductions in aerobic plate counts and S. Enteritidis were observed with slightly acidic electrolyzed water. The level of S. Enteritidis on egg shells gradually decreased during 20 days of storage at both $10^{\circ}C$ and $20^{\circ}C$, whereas S. Enteritidis survived longer at $20^{\circ}C$ than at $10^{\circ}C$. S. Enteritidis was not detected in eggs at $10^{\circ}C$, 2.13 log CFU/g of S. Enteritidis was detected in eggs washed with sodium hypochlorite after 20 days of storage at $20^{\circ}C$, indicating that S. Enteritidis penetrated into the egg shell during storage at $20^{\circ}C$. In conclusion, slightly acidic electrolyzed water increased microbial reduction and least affected quality of washed eggs. Thus, slightly acidic electrolyzed water can be recommended for washing of graded eggs, at retail markets.

• Journal of the East Asian Society of Dietary Life
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• v.7 no.4
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• pp.491-501
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• 1997

The purpose of this study was to investigate the storage and cooking of eggs in addition to the purchase of special eggs. This survey was tarried out through questionnaire and subjects were 429 housewives whose children were middle or high school students in Kyunggi-do and Inchon. Most housewives began to purchase special eggs one year ago. When housewives purchased special eggs, the first consideration was in order of nutrition, freshness, price and preference. The higher housewives' education level was, the higher they took nutrition into consideration. More than half of housewives replied that the proper package of special eggs was 10 eggs or more, and perceived that the period between producers of eggs and consumers was less than 5 days. Most housewives did the freshness test by checking roughness of shell surface or the interior quality of egg yolk and white after purchase. Also most housewives stored eggs in the inside rack of refrigerator door. Most housewives served dishes made from eggs more than 2 or 3 times per week and perceived that soft-boiled eggs are foods easy of digestion. These results suggested that it is necessary to supply fresh and nutritious eggs and to develop various dishes made from eggs for quickly-prepared meals.

• Korean Journal of Poultry Science
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• v.12 no.1
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• pp.39-44
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• 1985

These studies were conducted to compare the nutritive values and optimum prices of eggs among 6 groups of different egg Weight. With the total of 100 eggs of each weight group, after the weight percentage of egg yolk, albumen and shell in the whole egg were investigated, protein and fat contents of e99 yolk and albumen were analyzed. and then protein and fat contents in the whole eggs were calculated. Finally, the optimum prices of eggs in relation to the egg weight were studied on the basis of egg weight, protein content and protein plus fat contents of eggs, respectively. The results obtained are summarized as follows; 1. As the egg weight (X, g/10 eggs) increased, egg yolk (Y$_1$, %) and shell(Y$_2$, %) percentages tended to decrease, but egg albumen(Y$_3$, %) percentage increased lineally; Y$_1$=44.34-0.02X, Y$_2$=15.358-0.006 X, and Y$_3$=40.136＋0.026 X. 2. There were no significant differences in protein and fat contents of eggs among 6 different groups of egg weight. 3. Protein (Y$_1$, %), fat (Y$_2$, %) and protein plus fat (Y$_3$, %) contents in the whole eggs declined progressively as the egg weight (X, g/10 eggs) increased ; Y$_1$=11.943-0.00032X, Y$_2$=13.996-0.00614X, and Y$_3$=25.939-0.00646X. 4. Similar results were obtained whether the optimum prices of eggs were estimated on the basis of egg weight or protein content of eggs, and they were higher in the large size eggs and lower in the small size eggs than the optimum prices of eggs estimated on the basis of protein plus fat content of eggs.

• Journal of Animal Science and Technology
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• v.54 no.3
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• pp.209-217
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• 2012

The objective of this study was to assess the external and internal quality traits of eggs in wholesale egg market in Colombo, Sri Lanka and the effect of storage period in egg quality traits in the same market after receiving the eggs. First, a total of 482 fresh eggs were randomly collected from the above market and external egg quality traits were determined and recorded according to the definitions given in the Specification for Chicken Egg SLS 959:1992. After that, a total of 288 fresh eggs were randomly collected and various external and internal egg quality traits were measured and recorded according to the standard procedures over a storage period of 1, 3 and 5 d after receiving the fresh eggs to the wholesale market. Information about the shops was also collected using a pretested questionnaire. Using the recorded data, shape index, Haugh unit, albumen index and yolk index were calculated for each egg. Average weight, width, length and shape index of the eggs in the sample was 59.96 g, 4.33 cm, 5.78 cm and 75.03, respectively. Average shape index value was much closer to the standard value of 74. From the total sample 80.5% eggs had a normal and sound shape. However only 60.37% of the eggs are in the desirable quality range specified in SLS 959:1992, when the overall shell quality of the sample is considered based on shell cleanliness, defects and shape. The results of the current study indicated that eggs had significant (p<0.05) deterioration of all internal quality parameters tested with increasing storage time. However the effect was not significant (p>0.05) between the storage periods of 3 and 5 d after receiving eggs except for yolk color and yolk height. Desirable category of eggs had reduced and rejections had increased with the storage period. Main problems associated with the particular market were less space availability, higher percentages of dirty eggs, unavailability of proper packaging materials, no standard packaging system for eggs, and not implementing a standard grading system for eggs. Therefore the results of this study suggest that proper egg handling and storage conditions such as low temperature storage may be implemented to increase the proportion of desirable quality eggs in the above market.

• Fisheries and Aquatic Sciences
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• v.4 no.4
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• pp.208-218
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• 2001

We have investigated the gonad index (GI), gonadal development, reproductive cycle, first sexual maturity, sex ratio, the number of spawned eggs and spawning frequency of the Manila clam, Ruditapes philippinarum. Samples were collected from the intertidal zone of Komso Bay, Korea from January to December in 1999. Monthly changes in the gonad index (GI) and condition index showed a similar pattern in the reproductive cycle. The spawning period was once a year between early June and early October, there was a spawning peak between July and August when seawater temperature was over $20^{\circ}C$. The reproductive cycle of this species can be categorized into five successive stages; early active (February to March), late active (April to May), ripe (April to August), partially spawned (June to October), and spent/inactive stage (August to March). Percentages of first sexual maturity of female and male clams of l5.1-20.0mm in shell length were $56.3\%$ and $60.0\%$, respectively, and $100\%$ for the clams >25. mm. The sex ratio of individuals >15.1 mm in shell length was about 1:1 $(\chi^2= 0.02,\;p>0.05)$. Number of the eggs released from each clam by the induction increased as the size of clam in terms of shell length increased. Mean number of the eggs from the second induction of the spawning was $75.35-84.30\%$ $(average\;79.81\%)$ of the number of the eggs released in the first spawning. Our data indicated that R. philippinarum in Komso Bay has one major spawning peak with over two minor spawning, and the interval of each spawning was estimated to be approximately 15-17 (average 16.5) days.

• Asian-Australasian Journal of Animal Sciences
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• v.9 no.6
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• pp.723-726
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• 1996

A water loaded pressure device using water as the breaking force was developed to evaluate eggshell strength and compared with a dropping ball techniques. Further, relationships of shell thickness and weight of eggs to shell strength were also studied. Values for both of the shell strength measuring methods showed a highly significant correlation (p < 0.001) with shell thickness. The water loaded pressure method had a much higher simple correlation coefficient for shell thickness (r = + 0.786) than the dropping ball method (r = + 0.577). The shell strength measured by the water loaded pressure method appeared not to be correlated to egg weight. On the other hand, the negative sign of the standard partial regression coefficient and the partial regression coefficient of egg weight in the estimated multiple regression equation implied that for a given shell thickness a larger egg tended to have less shell strength than a smaller egg.

• Food Science of Animal Resources
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• v.37 no.2
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• pp.181-190
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• 2017

The aim of this study was to compare the quality and physicochemical characteristics of blue-shelled eggs (BE) and conventional eggs (CE). Proximate composition, quality, pH value, shell color, collagen content, fatty acid composition, total cholesterol, ${\alpha}$-glucosidase inhibition activity, and antioxidation activity were determined. The proximate composition, general qualities, and pH values of CE and BE showed no significant differences, except in moisture composition, weight, and shell thickness. Moisture content and weight of BE were significantly lower than those of CE. However, shell thickness and weight of BE were higher than those of CE (p<0.05). Lightness of BE was significantly higher than that of CE (85.20 vs. 58.80), while redness ($a^*$) and yellowness ($b^*$) of BE were lower than those of CE ($a^*$: -4.75 vs. 14.20; $b*$: 10.45 vs. 30.63). The fatty acid [C18:1n7 (cis-vaccenic acid) and C18:3n6 (gamma-linolenic acid)] contents of BE were significantly higher than those of CE. The total cholesterol contents of BE and CE were similar. DPPH radical scavenging activity of BE was significantly higher than that of CE (40.78 vs. 35.35). Interestingly, ${\alpha}$-glucosidase inhibition activity of whole egg and egg yolk in BE (19.27 and 36.06) was significantly higher than that of whole egg and egg yolk in CE (13.95 and 32.46). This result indicated that BE could potentially be used as a functional food material. Further studies are required to evaluate the specific compounds that affect functional activity.

• Food Science of Animal Resources
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• v.22 no.3
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• pp.252-258
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• 2002

The objective of the study was to investigate the effects of dietary conjugated linoleic acid (CLA) on the egg quality. The ISA Brown (200 days and 500 days) hens were assigned randomly to six diets containing 0, 0.6, 1.2, 1.8, 2.4 and 4.8% CLA, respectively. The CLA contents was not detected in control eggs, whereas the CLA contents of eggs that fed with CLA diets was significantly increased (p.0.05) as increasing of dietary CLA levels and feeding periods. Eggs weight, Haugh unit (HU), shell color, shell weight, shell density, and shell thickness were not significantly different among treatments. However, the albumen height from hens fed CLA was significantly (P<0.05) lower than those of control at 7 weeks. As increasing of the CLA levels in diet, the rate of saturated fatty acid in egg yolk was increased and yolk color showed more yellow color. Especially, T4 showed significantly (P<0.05) more yellow color than those of control in yolk color. When e99s were boiled, egg yolks from CLA dietary groups showed significantly (p<0.05) higher hardness value than control.