• 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.

• 한국축산식품학회지
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• 제38권1호
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• pp.14-25
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• 2018

Chemical compositions, trypsin inhibitory activity, and gelling properties of albumen from duck egg during salting of 30 days were studied. As the salting time increased, moisture content decreased, the salt content and surface hydrophobicity increased (p<0.05). Trypsin inhibitory activity and specific activity were continuously decreased throughout the salting time of 30 days (p<0.05). This coincided with the decrease in band intensity of inhibitor with molecular weight of 44 kDa as examined by inhibitory activity staining. Nevertheless, no differences in protein patterns were observed in albumen during the salting of 30 days. Based on texture profile analysis, hardness, springiness, gumminess, chewiness, and resilience of albumen gel decreased with increasing salting time. Conversely, salted albumen gels exhibited higher cohesiveness and adhesiveness, compared to those of fresh albumen. Scanning electron microscopic study revealed that gel of salted albumen showed the larger voids and less compactness. In general, salting lowered trypsin inhibitory activity and gelling property of albumen from duck egg to some extent. Nevertheless, the salted albumen with the remaining inhibitor could be an alternative additive for surimi or other meat products to prevent proteolysis.

• Asian-Australasian Journal of Animal Sciences
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• 제4권4호
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• pp.399-405
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• 1991

The interaction of 4 dietary crude protein (13, 16, 19 or 22%) and 4 metabolizable energy (2600, 2800, 3000 or 3100 kcal ME/kg) levels on egg quality performances of Starcross layers were assessed between 245 and 275 days of age. The egg weight increased significantly with the increasing dietary protein and energy levels. But egg shape index, albumen index, yolk index, yolk dry matter, yolk protein, yolk fat, albumen protein and shell tickness were similar at all dietary protein and/or energy levels. The egg specific gravity and albumen weight increased but the yolk, weight, Haugh unit and albumen drymatter decreased with the increase of dietary protein levels and showed irregular trend with energy levels. The albumen dry matter and egg shell weight, however, were not affected by energy and protein levels. Simultaneous increase of protein and energy increased specific gravity, albumen index and shell thickness at a greater rate than that increased by the increase of protein or energy alone.

• 한국가금학회지
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• 제17권3호
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• pp.211-216
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• 1990

난백단백질의 농도와 당류의 첨가수준이 난백의 열안정성에 미치는 영향을 검토하기 위하여 가열처리($120^{\circ}C$, 30분 또는 $90^{\circ}C$, 30분) 전후 난백겔의 조직감 및 색택을 측정하였으며 그 결과는 다음과 같다. 난백단백질의 농도가 낮아짐에 따라 난백겔의 경도는 열처리 조건에 상관없이 급격히 덜어졌으며 명도와 황색도는 점차 감소하였다. 응집성은 단백질 농도가 $8.3^{\circ}C$ 이하로 희석됨에 따라 증가하기 시작하였다. Sucrose 2.5%의 첨가로 난백겔의 경도가 다소 증가하였으나 그 이상 원가로 점차 저하하였으며 sucrose의 첨가로 응집성은 다소 저하하였다. Glucose의 첨가에 의해 고온처리 시 난백의 응집성은 다소 증진되었으나 명도가 감소하고 황색도는 저온처리의 경우에도 고온처리와 같이 높아졌다.

• 한국가금학회지
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• 제17권3호
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• pp.217-223
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• 1990

화학변형에 의해 난백의 열안정성을 증진시키기 위하여 acetic anhdride, succinic anhydrice 및 maleic anhydride 등을 사용하여 화학변형 된 난백친의 열처리 조건에 따른 특성을 검토하였다. 난백겔의 경도는 acetylatiorl과 succinylation에 의해 증가되었으며 고온처리의 경우($120^{\circ}C$, 30분)의 경우가 저온처리의 경우($95^{\circ}C$. 30분)보다 높은 값을 나타내었다. 응집성은 succinylation과 maleylation에 의해 증가되었으며 고온처리 시에는 화학변화에 의해서 모두 증가되었다, 난백겔의 명도( L value)는 maleylation에 의해 크게 감소하였으며 황색도( b value)는 화학변형에 의해 전반적으로 감소하였다. 난백의 초기 열변성온도는 acetylation에 의해 11$^{\circ}C$, maleylation에 의해 $12.5^{\circ}C$ 그리고 sucinylation에 의해 $14.5^{\circ}C$씩 증가하였다.

• 한국식품영양과학회지
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• 제24권1호
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• pp.82-91
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• 1995

This study was designed to elucidate the effects of lysozyme, clupeine, sucrose, and sodium chloride on the foaming properties of egg albumen and podered beef plasma. Surface tensions of egg albumen(5%, w/w) and powdered beef plasma(5%, w/w) adding to lysozyme, clupeine, sucrose, and sodium chloride were 46.8$\pm$0.379~52.4$\pm$ 0.404dyne/cm(control, 51.5$\pm$0.416dyne/cm) and 54.6$\pm$0.231~60.7$\pm$0.467dyne/cm(control, 53.9$\pm$0.153dyne/cm), respectively. Turbidities of the solutions were 77.0$\pm$0.058~97.9$\pm$ 0.058(control, 91.2$\pm$0.153) and 90.3$\pm$0.058~98.5$\pm$0.115 (control, 82.7$\pm$0.100), respectively. Surface hydrophobicities of the solutions were 524~811(control, 485) and 5102~ 7128(control, 4665), respectively. The solution with high hydrophobicity revealed good foaming properties. Analysis of egg albumen and powdered beef plasma foam by electrophoresis showed that lysozyme was retained for a long time in foam. The optimal concentraitons of lysozyme and clupeine for foaming properties were 0.5% and 0.3% in egg albumen(5%, w/w) and 0.5% and 0.5% in powdered beef plasma(5%, w/w), respectively. In case of egg albumen, sodium chloride dominantly enhanced the action of clupeine. The addition of 0.3% clupeine with sodium chloride(2.0M) to egg albumen(5%, w/w) increased overrun and foam stability by 119.5% and 70.9%, respectively. The addition of 0.5% clupeine to powdered beef plasma(5%, w/w) also increased overrun and foam stability by 43.7% and 127.3%, respectively.

• Asian-Australasian Journal of Animal Sciences
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• 제13권7호
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• pp.980-985
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• 2000

Influences of Japanese green tea powder (GTP) supplementation to commercial diet on laying performance and egg quality were studied by using 60 laying hens. The experimental diet with or without 0.6% GTP was given ad libitum to the birds during the period from 6 to 71 weeks of age. The birds started egg production from 21 wk of age regardless GTP feeding. Body weight, feed intake, egg weight tended to decrease with GTP supplementation, while egg production rate tended to increase. Haugh unit score was significantly increased with GTP, which accompanied with the increased albumen height. These were observed almost throughout the laying period over 50 wk. Gel proportion in thick albumen was decreased as storage time is prolonged, then higher values of the gel proportion were recorded in the eggs from GTP group. Thick albumen of the eggs from GTP-fed layers had more carbohydrate than that from control layers. All these indicate physical stability of thick albumen in the eggs from GTP group. Thiobarbituric acid content of egg yolk tended to remain lower in the eggs from GTP group during 5-10 days of storage at room temperature. Levels of egg yolk cholesterol and yolk lipid were significantly reduced by GTP feeding. There were no significant differences in eggshell weight, shell thickness and shell strength between the two groups. Thyroid gland and liver from hens slaughtered at 71 wk of age did not differ in weight irrespective of GTP feeding. The present results suggest that GTP could modify components of edible part of egg, leading to the characteristics favourable to consumers such as high durability of thick albumen and less cholesterol in yolk, without altering general performance of the layers throughout this year round experiment.

• 한국가금학회지
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• 제16권1호
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• pp.17-22
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• 1989

난백의 열광수성을 순화시키기 위하여 각종금속염(Fe$^{2＋}$, Fe$^{3+}$ , $Al^{3+}$ , Cu$^{2＋}$)을 첨가하고 가훈처리($60^{\circ}C$, 5분간) 전후 난백의 기능성을 검토하였으며 알루미늄염(Al$^{3+}$ )이 첨가된 난백의 pH에 대한효과도 검토하였다. 금속염의 첨가에 의해 가열처리 전후 난백의 탁도는 대체로 증가하였으나 알루미늄염의부가시 탁도의 변화가 가장 작았다. 난백의 기포력은 금속염의 첨가에 의해 전반적으로 증가하였으며 Fe$^{3+}$ 의 첨가효과가 가장 컸다. 특히 가열처리 후 난백의 기포력은Fe$^{3+}$ , Al/ sup 3＋/ 및 Cu$^{2＋}$의 첨가에 의해 크게 증가되었다. 기포안정성의 경우 열처리 전에는 Fe$^{3+}$ , Al/ sup 3＋/의 첨가효과가 있었으나 열처리 후에는 Fe$^{3+}$ 와 Al/ sup 3＋/의 첨가가 효과적이었다. 한편 알루미늄염을 첨가한 난백을 pH 7 -10의 범위에서 가열처리한 결과 pH 7-8.5 범위에서는 탁도 및 기포성의 변화가 크지 않았고 pH 9이상에서는 탁도와 기포성은 낮아졌으나 기포안정성은 향상되었다. 난백액에 Salmonella typhimurium을 $10^{6}$ cells/$m\ell$수준으로 접종 후 $60^{\circ}C$, 5분간의 가열처리 결과 pH에 상관없이 모두 사멸되었다.

• 한국가금학회지
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• 제19권1호
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• pp.1-12
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• 1992

본 시험은 난백 129g에 자당(백색) 150g을 첨가한 구와 난백 161g에 자당 150g을 첨가한 2구로 나누고, 다시 각 구를 난황 0g, 8.71g, 17.43g 및 26.14g, 14g 첨가구로 4구분 하였다. 각 구는 5$0^{\circ}C$ shaking water bath(Tecom 58-16, U.K)내에서 1분간 92회 왕복속도로써 2, 4, 6, 8, 10및 12시간 후까지 경시적으로 pH와 비중을 측정하였다. 측정회수는 3회로써 그 평균치를 시험성적으로 하였으며 비중은 비중계로써 측정하였던 바 얻은 본 시험의 결과는 다음과 같다. 1. 전 시험구간에 있어서 shaking시간에 따라 pH와 비중은 경시적으로 증가되었으나 난황 및 난백의 첨가량에 따라 그 변화는 상이한 결과를 보였다. 2. 난백 129g 첨가구와 161g 첨가구에 있어서 shaking시간이 경과함에 따라 일정한 수준의 자당과 난황을 혼합했을 때는 난백의 첨가량이 많을수록 pH는 더 높아지고 비중은 낮아지는 결과였다. 3. 난백 161g 첨가구에 있어서 shaking 10시간 후의 PH는 8.60으로써 최고치였으며, 그 후에는 낮아졌다. 난백 129g 첨가구에 있어서 shaking 12시간 후의 pH는 8.39로써 최고치였으며 shaking 10시간 후부터 점차 낮아지는 경향이었다. 두 구간의 pH 최고치가 나타나는 시간의 상이는 난백의 첨가량에 의한 것으로 사료된다. 4. 전체설험구간에 있어서 난황을 무첨가한 구가 첨가한 구보다 pH와 비중이 모두 높았다. 5. 자당 150g에 난백 129g, 난황 0g, 8.17g, 17.43g 및 26.14g을 각각 첨가하여 12시간동안 shaking water bath 내에서 조사한 pH와 비중의 성적간에는 상관관계를 검정한 결과, 상관도는 높았으며(r＝0.9692$^{**}$ ) 그 회귀방정식은 Y＝0.050十0.145X였다. 6. 자당 150g과 난백 161g, 난황 0g, 8.17g, 17.43g 및 25.14g을 각각 첨가하여 12시간동안 shaking water bath내에서 조사한 pH와 비중의 성적간에 상관관계를 검정한 결과, 상관도는 높았으며(r＝8963$^{**}$ ) 그 회귀방정식은 Y＝0.294＋0.110X였다.

• Asian-Australasian Journal of Animal Sciences
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• 제28권6호
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• pp.855-861
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• 2015

Lactobacillus plantarum is used for fermentation of fish products, meat and milk. However, the utilization of these bacteria in egg processing has not been done. This study was designed to evaluate the potential of fermented egg albumen as a functional food that is rich in angiotensin I-converting enzyme inhibitors activity (ACE-inhibitor activity) and is antihypertensive. A completely randomized design was used in this study with six durations of fermentation (6, 12, 18, 24, 30, and 36 h) as treatments. Six hundred eggs obtained from the same chicken farm were used in the experiment as sources of egg albumen. Bacteria L. plantarum FNCC 0027 used in the fermentation was isolated from cow's milk. The parameters measured were the total bacteria, dissolved protein, pH, total acid and the activity of ACE-inhibitors. The results showed that there were significant effects of fermentation time on the parameters tested. Total bacteria increased significantly during fermentation for 6, 12, 18, and 24 h and then decreased with the increasing time of fermentation to 30 and 36 h. Soluble protein increased significantly during fermentation to 18 h and then subsequently decreased during of fermentation to 24, 30, and 36 h. The pH value decreased markedly during fermentation. The activities of ACE-inhibitor in fermented egg albumen increased during fermentation to 18 h and then decreased with the increasing of the duration of fermentation to 24, 30, and 36 h. The egg albumen which was fermented for 18 h resulted in a functional food that was rich in ACE-inhibitor activity.