• Journal of Life Science
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• v.30 no.10
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• pp.860-866
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• 2020

This study examined the characteristics of eggs obtained from layer chickens reared with feed that included Tenebrio molitor larvae, which were in turn bred using feed that included dried food waste powder. The eggs showed a tendency to be slightly thinner in the treated groups, but the Haugh unit indicating freshness was higher in the treated groups than the control group, and the 5% larval-treated group showed the highest value. The color of the yolk tended toward higher redness, lower brightness, and lower yellowness in the 5%-treated group, which also showed similar crude fat and protein values to the control group; the 10%- and 15% larval-treated groups had lower crude fat and protein values, although the carbohydrate content was higher. Structural amino acids in the treated groups showed a higher ratio of non-essential amino acids to essential amino acids than the control. The polyphenol content, which is an index of antioxidants, was highest in the 5%-treated group, and it is thought that this may affect the storage and antioxidant properties of the eggs. Thus, when employed with a feed source to maintain high protein and high fat, T. molitor larvae may cause critical changes in the nutrient content of eggs and improve their freshness.

• Journal of the Korean Chemical Society
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• v.49 no.6
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• pp.531-536
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• 2005

• Applied Biological Chemistry
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• v.43 no.4
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• pp.260-265
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• 2000

To determine the quality change of the irradiated eggs during storage, fresh shell eggs were irradiated using $^{60}Co$ at 0, 1, 5, 10, 30 kGy and stored for 30 days. The york index, color, pH, viscosity, egg weight, and SDS-PAGE profile of the irradiated eggs were examined. During storage, york index values of the irradiated eggs and the control were decreased and the increase of dose decreased yolk index. However, the yolk index values were increased temporarily at 10 kGy and 30 kGy. The yolk color had a bright yellow with increases in dose level and there was no significant change during storage. The albumen viscosities were decreased with increases in dosage and were decreased during storage. Also, the albumen pH values of the irradiated eggs were higher than that of the control and were increased during storage. The weight losses of eggs were increased during storage and there were no significant changes by dose level. SDS-PAGE profile of the egg white proteins of the shell eggs showed the change in molecular weight distribution and had aggregation pattern as well as degradation. CD and fluorescence spectroscopy study showed changes in the secondary and tertiary structure of egg white proteins by ${\gamma}-irradiation$. Therefore, this study clearly indicates that irradiation dose of eggs should be appropriate to prevent the loss of egg qualities.

• Food Science and Preservation
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• v.21 no.5
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• pp.609-617
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• 2014

This study was conducted to identify quality indicators of the freshness of chicken eggs circulating in domestic markets. We first stored freshly-laid eggs at temperatures of 0, 10, 20, and $30^{\circ}C$, investigated their weight-loss rate, specific gravity, color, york index, albumen index, Haugh unit (HU), pH, and sensory evaluation, and finally analyzed the correlation between each quality characteristic and the sensory preference. At all the storage temperatures, the quality characteristics of the weight-loss rate, specific gravity, yolk index, albumen index, and HU showed significant correlations (p<0.05) with the preference. In particular, the temperature-dependent correlation between the quality characteristics and the sensory preference was significantly higher with increasing storage temperatures and weight-loss rates (r = -0.78; r = -0.93; r = -0.95; and r = -0.99), albumen index (r = 0.66; r = 0.89; r = 0.89; and r = 0.93), and HU values (r = 0.64; r = 0.92; r = 0.96; and r = 0.98) at 0, 10, 20, and $30^{\circ}C$, respectively (p<0.01). The Color and pH examinations yielded disparate results, and further research is needed to determine the methods of using the characteristics as quality indicators. We believe that the changes in the weight-loss rate, specific gravity, yolk index, albumen index, and HU are adequate quality indicators of the freshness of egg in circulation.

• KOREAN POULTRY JOURNAL
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• v.36 no.7 s.417
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• pp.64-65
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• 2004

닭고기 신선육을 대량으로 소비하는 대형 매장에서는 이번 여름 복(伏) 경기를 어떻게 진단하고 준비하고 있는지 서울 롯데마트 잠실점 계육$\cdot$계란 바이어 이권재 과장(MD)을 찾아 현장의 목소리를 담았다.

• Korean Journal of Poultry Science
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• v.41 no.2
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• pp.135-142
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• 2014

This study was conducted to evaluate dietary effects of Marigold extract on laying performance, egg quality, oxidative stability of egg yolk and lutein transfer into chicken eggs. A total of one-hundred eighty nine 55-wk-old Hy-Line Brown layers were divided into seven groups and fed control diet or each experimental diet containing 0.1, 0.3, 0.5, 1.0, 1.5 or 2.0% Marigold extract. Egg production, egg weight and daily egg mass were not affected by dietary treatments. The yolk colors in groups fed diets containing Marigold extract were significantly higher than that of control. The Haugh unit were tended to be improved by feeding of diets containing Marigold extract although there were no significant difference in egg shell strength and thickness. The MDA (malondialdehyde) contents in groups fed diets containing Marigold extract above 0.5% were significantly reduced than that of control. After 14d of storage, the Haugh unit values in groups feed diets containing 0.3 and 1.0% Marigold extract were significantly higher than that of control (p<0.05). The concentration of lutein in egg yolk increased by feeding of Marigold extract. When 2% Marigold extract was supplemented to the diet, lutein content of egg was increased as much as 1.71 mg/60 g. These results indicated that the use of Marigold extract in layer diets was effective in egg quality and for the production of lutein fortified eggs.

• KOREAN POULTRY JOURNAL
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• v.44 no.3
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• pp.128-132
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• 2012

난가공 전문회사 농업회사법인 세양(주)은 친환경 신선한 계란을 생산하기위해 21만수 규모의 산란계농장을 설립했다. 지난해 3월 충북 음성군 삼성면에 착공을 시작으로 그해 10월 첫입식과 함께 지금은 한창 산란피크를 올리고 있다. 이 농장은 1개동 계사에 21만수 전수사육이 가능하도록 최신식 무창계사를 신축했고, 무엇보다 환기와 차단방역에 중점을 둔 시설설비로 총 74억 원의 어마어마한 투자 비용이 소요되면서 주목받고 있다. 농업회사법인 세양(주) 음성농장(이하 음성농장)의 강구만 대표를 만나 농장에 대해 보다 자세히 들어 보았다.

• KOREAN POULTRY JOURNAL
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• v.33 no.8 s.382
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• pp.116-120
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• 2001

1993년 UR협상타결 이후 닭고기 및 계란의 시장개방에 대비하여 1994닭경쟁력강화대책이래 1998 양계산물 유통개혁대책 시행으로 양계단지 및 닭계열화 등 시설의 자동화$\cdot$규모화로 사육기반시설은 확충되었으나, 양계산물 유통은 전근대적이고 제도의 미흡으로 인한 양계업 발전의 제약요인이 되고있고, 닭고기 수입자유화(1997.7.1)와 IMF사태 등의 어려운 시기를 거치면서 양계산물의 특성상 가격변동 주기가 짧고 질병이 빈번히 발생하는 등으로 인한 가격진폭이 커 수급과 가격이 불안정한 상태이다. 이에 농림부는 지난달 생산과 수급안정, 유통구조 개선을 위하여 닭고기$\cdot$계란의 등급제 도입을 통한 품질차별화와 신선육$\cdot$부분육 유통체계 구축으로 닭고기의 내수기반을 다지고 닭고기 수출을 확대함으로서 양계산업이 안정적으로 발전할 수 있도록 하는 양계산업발전대책을 발표하였다.

• Korean Journal of Food Science and Technology
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• v.46 no.3
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• pp.295-302
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• 2014

This study investigated the effects of storage temperature and time on the physicochemical properties of eggs, and the corelationship of quality factors with egg freshness and the palatability during storage. As storage temperature and time increased, weight loss significantly increased (p<0.05), while the specific gravity, Haugh unit, yolk index, albumen index, and yolk viscosity decreased significantly (p<0.05). A multiple regression equation of $Y_1$ (freshness)=$106.50286-0.81196X_1$ (weight loss)-$77.51667X_5$ (specific gravity)-$2.27156X_8$ (yolk pH)+$0.00178X_{16}$ (yolk viscosity) with $r^2$=0.89 was obtained for the evaluation of egg freshness. Also, sensorial palatability through the multiple regression equation was determined as $Y_2$ (palatability)=$104.98174-0.81466X_1$ (weight loss)-$76.53434X_5$ (specific gravity)-$2.20338X_8$ (yolk pH)+$0.00178X_{16}$ (yolk viscosity) with $r^2$=0.89 indicating that weight loss, specific gravity, yolk pH and yolk viscosity are major factors that affect the freshness and palatability of eggs during storage.

• Korean Journal of Poultry Science
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• v.43 no.4
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• pp.229-233
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• 2016

This study was conducted to compare three commercially available egg testing devices for measuring egg quality. The devices used were a Laser-type (automatic), a Ultrasonic-type (automatic), and a Probe-type (manual). Fresh eggs weighing 60~68 grams were obtained from a commercial hen farm. Three trials were conducted. In Trial 1, a total of 50 eggs were successively analyzed by the three egg testing devices. In Trial 2, fresh eggs were successively analyzed by a combination of two egg testing devices. In Trial 3, a total of 600 eggs (weighing 60~68 grams) laid by same flock were selected, further divided into three sub-groups with a total of 200 eggs, and analyzed by an egg testing device. In Trials 1 and 2, no apparent difference was observed in egg weight between egg testing devices. However, albumin height was scored highest in the Ultrasonic-type egg tester followed by the Probe-type and Laser-type (Trials 1 and 2). Consequently, the Haugh unit was similarly altered. Yolk color was highest in the Laser-type egg tester followed by the Ultrasonic-type and Probe-type (Trials 1 and 2). When fresh eggs laid by a single flock were independently analyzed by three devices, egg weight did not differ, but albumin height and Haugh unit were higher (p<0.05) in the Ultrasonic-type egg tester than in the Probe-type or Laser-type testers. However, Laser-type testers produced higher (p<0.05) yolk color values than the Ultrasonic-type or Probe-type egg testers. In conclusion, the commercially available egg testing devices exhibited performance differences in measuring egg qualities, which warrants further consideration as to whether the magnitude of bias and precision between the devices could be acceptable in the egg grading system, especially when assessing eggs stored for certain durations.