• 한국가금학회지
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• 제20권1호
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• pp.33-41
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• 1993

세척란의 저장성에 영향을 주는 여러 가지 요인 중에서 저장중의 온도 및 습도는 계란의 품질에 가장 큰 영향을 주는 요소로서 낮은 온도와 높은 습도에서 저장하는 것이 품질의 변화를 최소화할 수 있겠다. 또한 계란의 세척 시 사용하는 세척수의 온도, 이물질의 혼합 정도 그리고 세척방법도 계란의 저장성에 영향을 미치는 요인으로 지적되었다. 세척 시 소독제를 처리한 시험구는 물만으로 세척한 처리구가 세척하지 않은 처리구에 비해 계란의 부패율을 떨어뜨리는 결과를 얻을 수 있었으며 난각의 표면에 도포제 처리를 한 경우에는 계란 내부의 수분증발을 억제하고 외부로부터 미생물의 침투 등을 방지하는 효과를 가져 와 세척란 또는 미세척란보다 저 장성이 연장되는 결과를 나타내었다. 따라서 세척란의 경우에도 난각의 미생물 오염도를 줄이고 적절한 처리를 할 경우 장기저 장이 가능한 것으로 사료된다.

• Asian-Australasian Journal of Animal Sciences
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• 제5권3호
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• pp.461-464
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• 1992

A survey of the cholesterol content of eggs obtained from commercial sources in Korea was conducted. Eggs from 17 different strain birds were obtained from the Poultry Random Sample Test Station at Ansung, Kyonggi province. Yolk cholesterol contents, determined by the colorimetric procedure, were obtained from three consecutively laid eggs from birds of about 63 weeks of age. The overall mean of cholesterol value was 17.25 mg/g of wet yolk and ranged from 16.40 to 18.18 mg/g yolk. Analysis of t-test between white shell eggs and brown shell eggs showed no difference in cholesterol content: however, the white shell eggs were somewhat high in cholesterol (17.41 vs. 17.08 mg/g yolk). Significant differences (p<0.05) were found in yolk cholesterol contents among strains within the breed.

• Asian-Australasian Journal of Animal Sciences
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• 제15권1호
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• pp.1-6
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• 2002

Eggs obtained from 46 and 42 weeks old meat (Hybro) and layer (Leghorn) breeders flocks, respectively were used to examine the effects of genetic type of birds and egg size (small, medium and large) on variables of eggshell characteristics and hatchability traits. The variables measured were egg weight (EW), egg surface area (ESA) and eggshell characteristics (shell conductance (EC), per cent shell (PS), shell thickness (ST), shell volume (SV), shell density (SD) and hatchability traits (per cent hatchability (HP), early dead embryos (ED), late dead embryos (LD), pips with live embryos (PL) and pips with dead embryos (PD)). Genetic type of bird influenced all egg characteristics and HP of eggs. Eggs produced by the small Leghorn bird had lower EW, ESA, EC, ST, SV and HP than those produced by the heavy Hybro bird. The reduction of HP was associated with an increase in the percentage of ED and PL. Egg size influenced all variables measured except ST. Small size eggs had lower EW, ESA and EC and higher PS and SD than those of large eggs. Medium size eggs produced a higher HP when compared with that of large size eggs. The reduction of HP in large eggs was associated with higher percentage of ED, LD and PL. There were significant interactions between the genetic group of birds and egg size on LD and HP. Large egg size of Hybro birds had higher LD and lower HP than those of small size eggs produced by the same flock. However, There was no difference in HP and LD among the different egg sizes produced by Leghorn birds. It was concluded that genetic make up of birds and egg size influence eggshell characteristics and HP. The type of bird (heavy or small) influences the optimum egg size for successful hatching. Attention should be given to the size and eggshell characteristics of eggs of breeders' flocks for achieving maximum HP.

• 한국가금학회지
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• 제43권1호
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• pp.31-38
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• 2016

Consumers demand fresh and high-quality eggs. Egg quality may be represented by shell color, shell weight, egg weight, shell thickness, shell density, albumen height, yolk color, albumen pH and viscosity. Various factors such as strain, age of hen, storage temperature, humidity, the presence of $CO_2$ and storage time affect egg quality. Therefore, we investigated the effects of storage time and temperature on egg quality to define the freshness of Korean market eggs. A total of 1,800 eggs were used for this experiment and were separated into 45 treatments with 40 eggs in each. The treatments were consisted of 15 storage periods (2 d to 30 d) and 3 storage temperatures ($2^{\circ}C$, $12^{\circ}C$, $25^{\circ}C$). Each egg was weighed and broken, and the height of the thick albumen, Haugh units (HU), egg shell color and yolk color were measured by a QCM+system. We also observed the physiochemical properties of eggs such as yolk pH, albumen pH and albumen viscosity. The egg weight, shell weight, albumen height, HU and albumen viscosity significantly decreased with increasing storage time and temperature. However, the albumen and yolk pH significantly increased with increasing storage period and temperature. The interaction effects between the storage period and temperature were significant for shell weight, shell density, egg weight, albumen height, HU, yolk color, yolk pH, albumen pH and albumen viscosity. In the analysis of the correlation with egg quality, the storage temperature exhibited a higher correlation coefficient than the storage period. In conclusion, storage time and temperature are the major factors affecting egg quality, but the storage temperature is a more sensitive determinant of egg quality deterioration compared with the storage period.

• Asian-Australasian Journal of Animal Sciences
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• 제30권7호
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• pp.1013-1020
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• 2017

Objective: Stripe marks, which occasionally occur on the shell, do not cause breakage to the shell and shell membranes of eggs. This study investigated the quality of intact eggs (IEs), minor stripe-marked eggs (MEs), severe stripe-marked eggs (SEs), and cracked eggs (CEs) during 3-week storage at $25^{\circ}C$. Methods: Shell eggs were collected the day after being laid and were washed. Among them, eggs without any visual cracks or stripe marks on the shells were evaluated as IEs by the plant employees using candling in a darkened egg storage room; the remaining eggs exhibited some eggshell defects. At day 3, the eggs were further categorized into IEs, MEs, SEs, CEs, and broken eggs (BEs) on the basis of the description given. Except BEs, which were discarded, the remaining eggs were stored at $25^{\circ}C$ (approximate relative humidity 50%) and then analyzed. Results: Stripe marks were observed primarily within the first 3 days after washing. At day 3, CEs had significantly (p<0.05) lower Haugh unit values, but all eggs had grades AA or A, according to the United States Department of Agriculture standard. As storage time increased, differences in egg quality between groups were more obvious. IEs had the highest eggshell breaking strength. During storage, the total plate counts and pathogens, namely Escherichia coli, Campylobacter spp., Staphylococcus aureus, and Salmonella spp., were not detectable in the internal content of IEs and SEs. Conclusion: In conclusion, cracks degraded egg quality severely and minor stripe marks only slightly influenced the egg quality.

• 한국유기농업학회지
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• 제24권1호
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• pp.115-122
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• 2016

The main purpose of the current study was to compare quality of eggs 1) produced from hens housed in battery cages vs. free range, 2) from young vs. old hens, and 3) tagged with the lowest vs. the highest price in a local franchised mart. The ages of hens, at which their eggs were used for the analysis of quality, were 70 weeks old in the experiment 1, 22 and 47 weeks old in the experiment 2, and were unknown in the experiment 3. Eggs were analyzed for weight, albumen height, Haugh unit, shell color, shell strength, shell thickness, shell weight, yolk color, yolk weight, and egg white weight. In the experiment 1, significant differences were detected between two housing systems in shell color, shell weight, yolk color, and yolk weight (P<0.05), but not in egg weight, albumen height, Haugh unit, shell strength, shell thickness, and egg white weight (P>0.05). Although egg weight was slightly but not significantly higher in battery cages by 2.2 g than in free range, yolk weight was significantly higher in battery cage (P<0.05). On the contrary, shell color was greatly increased in free range system by 68.5% compared with battery cage. In the experiment 2, there were significant differences between young and old hens in egg weight, albumen height, Haugh unit, shell strength, shell weight, yolk color and yolk weight (P<0.05). Egg weight, shell weight, yolk color and yolk weight were increased in old hens than young hens while albumen height, Haugh unit, and shell strength were decreased. In the experiment 3, egg weight, albumen height, Haugh unit, shell weight, and egg white weight were significantly higher in the highest priced eggs than the lowest ones (P<0.05), whereas shell strength and yolk color were lower (P<0.05) but shell color, shell thickness and yolk weight were not different (P>0.05). So, egg freshness was clearly higher in the highest priced ones than in the lowest (P<0.05). Due to the limited information on raising and husbandry of laying hens whose eggs were tested for egg quality in the current study, the present results should be cautiously interpreted while contributing to the future study as a basis in this field.

• Asian-Australasian Journal of Animal Sciences
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• 제15권2호
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• pp.297-302
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• 2002

The effects of eggshell pigmentation and egg size (medium and large) on the spectral properties and characteristics of eggshells were examined in eggs from two genetic groups of breeder flocks. Birds from meat (Hybro, pigmented eggshell, PES) and layer (Leghorn, non-pigmented eggshell, NPES) at 40 and 46 weeks of age, respectively, were used. Measurements of per cent shell (PS), shell thickness (ST), shell volume (SV), shell density (SD), egg shell conductance (EC) and physical dimensions of eggs were made. The spectral properties of eggshells were measured over the wavelength (WL) range of 200 to 1,100 nm. Eggshell absorbed approximately 99.8 percent of the light and transmitted only about 0.12 percent with a maximum light transmission at the near-infra-red region of about 1075 nm. It attenuated shorter WL and transmitted longer WL. Eggshell pigmentation and egg size influenced light transmission into the egg. The NPES had higher EC and transmission of light and lower PS and SD than those of the PES. Large size eggs had higher EC, SD, SV, transmission of light and egg physical dimensions than those of medium size eggs. It is concluded that genetic make up of birds and egg size influenced eggshell characteristics including EC and that, as a consequence, the difference in the spectral properties of eggshells. The pigmentation of eggshell influenced the amount and WL transmitted into the egg. The size and EC of eggs influenced the amount of light transmitted through the eggshell. EC is a good indicator for the ability of eggshell to transmit light.

• 한국가금학회지
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• 제7권2호
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• pp.47-53
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• 1980

본 시험은 메추리의 난각과 난각막의 두께 변화를 구명하기 위해서, 공시난 520개로부터 다음과 같은 결과를 얻었다. 1) 메추리 란의 외모색에 따라 구분한 사종의 난각은 그 색에 따라서 대반점백색난각. 대반점난각, 소반점보라난각, 소반점베이지난각으로 구분되고, 그 평균 란중은 8.993g, 8.866g, 8.403g, 8,109g이었다. 2) 사종 난각의 평균 두께는 대기점백색락각이 0.171mm, 대반점각이 0.169mm. 소반점베이지난각이 0.160mm, 소반점보라난각이 0.156mm였다. 3) 사종의 난각막의 평균 두께는 대반점 난각이 0.0449mm. 대연점백색난각이 0.0431mm, 소반점베이지난각이 0.398mm 소반점보라난각이 0.0397mm였다. 4) 난각과 난각막의 두께간에서 빈의 상관계수가 나타났으나 유의성은 없었다. 5) 일반적으로 난각의 두께가 닭에 비하여 매우 엷었다. 그러나 난각막의 두께는 대동소이했다.

• International Journal of Industrial Entomology and Biomaterials
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• 제4권2호
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• pp.149-153
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• 2002

Induction of non-diapause eggs and manifestation of quantitative characters were studied in different seasons by low temperature incubation of eggs of a low yielding diapause with coloured cocoons silkworm breed, RDI of Bombyx mori. Hundred percent of nandiapause eggs were induced when the egg incubation was carried out at 15$^{\circ}C$ followed by incubation initially at $25^{\circ}C$ and then at $15^{\circ}C$. The diapause-nondia-pause relation was found to be reversible. Analysis of variance study demonstrated significant variation in all the quantitative characters whereas significant variation due to different incubation treatments was observed for larval span, fifth instar larval span, cocoon yield/10,000 larvae by weight, cocoon weight, cocoon shell weight, and cocoon shell ratio. study on hybrid vigour skewed significant heterosis over mid parent value for four economic characters viz., cocoon weight, cocoon shell weight, cocoon shell ratio and filament length in a Fl hybrid between RD1 with diapause eggs and Japanese type bivoltine $NB_{4} D_{2}$.

• 농업과학연구
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• 제49권4호
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• pp.909-921
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• 2022

Eggs are considered an excellent complete food because they contain many major energy sources, including protein. Eggs are one of the most widely consumed foods worldwide, and egg consumption is steadily increasing. Eggs are generally classified according to their quality and weight. Various characteristics of eggs must be considered for the design and effective utilization of equipment used for the transport, processing, packaging, and storage of eggs. In this study, egg surface area, volume, density, etc. were measured according to the grade of the egg. The values of several geometrical properties that were measured tended to increase with increasing egg grade. The smallest grade eggs had the lowest shell thickness and density. The electrical conductivity of the eggshell and its contents was measured with a self-made electrode and equipment. The egg shell showed properties similar to insulators, and as the thickness increased, the electrical conductivity tended to increase. The electrical conductivity of the egg yolk showed almost constant values under all conditions. The electrical conductivity of the egg white and mixture was particularly low at 0.1 kHz. Fouling and electrode corrosion occurred in a low frequency region due to the egg white. In this study, various geometric and electrical characteristics of eggs were measured, and based on this, factors that could serve as new indicators for egg processed production were analyzed and investigated.