• Korean Journal of Poultry Science
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• v.43 no.1
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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.

• 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.

• Journal of Food Hygiene and Safety
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• v.4 no.1
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• pp.29-36
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• 1989

In order to investigate the Storage time of chicken eggs, several physico-chemical tests from chicken eggs store at 5, 13 and 27$^{\circ}C$ were examined. Egg samples were collected from six poultry farms. Egg stored at 5$^{\circ}C$ based on the depth of air cell and specific gravity, were all acceptable until 17 days ; on the egg yolk coefficient and pH of the egg white and egg yolk until about 10 days. Egg stored at 13$^{\circ}C$, based on the depth of air cell. were acceptable by about 10 days of storage, but on the other physico-chemical tests by about 7 days. Egg samples stored at room temperature(about 27$^{\circ}C$) base on the depth of air cell, were acceptable by about 5 days of storage ; on the specific gravity by 4 days ; and on the egg yolk coefficient and pH of the egg yolk and egg white by 3 days. The results of this study showed that egg stored at 5$^{\circ}C$ were considered acceptable by 10 days of storage ; at 13$^{\circ}C$ by 7 days ; at room temperature (27$^{\circ}C$) by 3 days.

• Korean Journal of Food Science and Technology
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• v.20 no.4
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• pp.594-599
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• 1988

Methods by which liquid egg could be stored in liquid state at frozen storage temperature$(-15^{\circ}C)$ with selected cryoprotectants and enzyme treatment were investiated, and quality changes in samples during storage were examined. The concentration of cryoprotectants (45% fructose and 55% glucose) to be added to egg yolk and whole egg to store them at $-15^{\circ}C$ in unfrozen state were 45.2% and 70.3%, respectively. Changes in consistency, precipitation of protein and microstructure of egg samples during storage indicated that adding cryoprotectants to liquid egg could effectively inhibit development of gelation during storage at $-15^{\circ}C$. Treating liquid egg with 0.15% papain could inhibit gelation during storage to some extent.

• Korean Journal of Veterinary Service
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• v.28 no.3
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• pp.225-234
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• 2005

Egg has been considered as one of the most important food sources in both nutritionally and economically. However, because the hazards of egg flow chains' complexity from producers to consumers and the insufficiency of cold chain systems in Korea are still remained, preventive measures for egg safety should be established. This experiment was carried out to investigate the changes of egg qualify during storage in order to find out the proper storage condition and eggshell treatment. Eggs were stored at cold condition $(5^{\circ}C,\;relative\;humidity;\;RH:\;65\pm3\%)$ and room Condition $(1st: Sep\; 6\~Nov\; 15,\;2001,\; 10\~30^{\circ}C,\;RH\;41\~86\%,\;2nd;\; Dec\;13,\;2001\~Feb\;21,\;2002,\;4\~23^{\circ}C,\;RH\;36\~89\%)$ after eggshell treatment (unwashed, washed and coated egg) during'10 weeks and examined weight loss and interior quality periodically. Weight loss was in decreasing order room washed > room unwashed > cold washed > cold unwashed > room coated > cold coated egg. And, Haugh unit was decreasing order room washed > room unwashed > room coated > cold washed > cold unwashed > cold coated egg. Our findings show that both coated eggs and refrigeration reduces the rate of decline in Haugh units and egg weight. And, washed eggs had lower average Haugh units and a higher weight loss than any of the eggshell treatment in both storage conditions. Conclusively, for washing eggshell, 150 ppm of sodium hypochlorite, regular exchange and temperature control of water should be consistent and also eggs should be dried immediately after washing. Also, national guidelines for temperature and moisture of storage places, transportation and expiration data should be established to keep quality and weight loss of eggs. Storage temperature that is a critical factor in the quality and safety of eggs should be kept under 12'c and labelling of expiration date should be obligatory.

• Asian-Australasian Journal of Animal Sciences
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• v.32 no.6
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• pp.881-890
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• 2019

Objective: A study was conducted to develop non-dairy creamer analogs/mimics using egg white, egg yolk, soy protein and their combinations, and their nutrient content, shelf-life and flavor acceptability were compared. Methods: Spray dried egg white, egg yolk, and soy protein isolate were purchased from manufacturers and used for the formulae. Results: The protein contents of the non-dairy creamer analogs/mimics were about 8.5% as calculated. The amounts of oleic and linoleic acid content increased as the amount of yolk increased in the formula, but the increases of polyunsaturated fatty acids were <0.5% of total fat. Addition of egg yolk to the formula increased choline and lutein content in the products, but the amounts were <0.4 mg/g for choline and $4{\mu}g/g$ for lutein. The lutein in the products continued to decrease over the storage time, and only about 15% to 20% of the 0-month amounts were left after 3 months of storage. Although the thiobarbituric acid reactive substances values of the spray-dried non-dairy creamer analogs/mimics increased as storage time increased, the values were still low. Yellowness, darkness, and egg flavor/odor of the non-dairy creamer analogs/mimics increased as the amount of egg yolk in the formula increased. The overall acceptability of the non-dairy creamer analogs/mimics was closely related to the intensity of egg flavor/odor, but storage improved their overall acceptance because most of the off-odor volatiles disappeared during the storage. Water temperature was the most important parameter in dissolving spray-dried non-dairy creamer analogs/mimics, and $55^{\circ}C$ to $75^{\circ}C$ was the optimal water temperature conditions to dissolve them. Conclusion: Higher amounts of yolk and soy protein combinations in place of egg white reduced the cost of the products significantly and those products contained better and balanced nutrients than the commercial coffee creamers. However, off-flavor and solubility were two important issues in the products.

• Korean journal of food and cookery science
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• v.18 no.1
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• pp.81-86
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• 2002

Yackwa was prepared by the addition of different amounts of egg white, and the samples were analyzed by texture profile analysis, Hunter's colorimetry and sensory evaluation during 5 days of storage. Tn texture profile analysis, the hardness, gumminess and chewiness of Yackwa were increased in all the samples during storage and the texture parameters were increased by increasing egg white level. No significant difference was observed in the lightness, redness and yellowness (p〉0.05), but Hunter's color values were slightly increased during storage in all the samples. In sensory evaluation, no significant difference was observed among the samples during storage except the increase of crispiness and overall acceptance by the addition of egg white. The results showed that Yackwa prepared with 10 g of egg white/(100 g of other ingredients ---약과재료 얼마당 10g 첨가인지 명확히 해야 함) had an acceptable sensory quality.

• Journal of Animal Science and Technology
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• v.64 no.2
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• pp.365-379
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• 2022

The present study was conducted with the aim of investigating the effect of storage length, turning frequency and egg position on internal quality traits of chukar eggs obtained from 56-week-old chukar partridges under the same nutrition and management conditions. A total of 720 eggs were collected and assigned to 36 subgroups according to storage length (7, 14, 21, and 28 d), turning frequency (0, 1, and 24 per day) and egg position (pointed end up, blunt end up and horizontal). As a result of the study, almost all the internal quality traits of chukar eggs were negatively affected by lengthening of storage period especially 21 days and longer (p < 0.001). Internal egg quality traits weren't statistically affected by turning frequency except yolk index (p < 0.01). An improvement was observed in Haugh unit, albumen index and heigh of eggs stored with pointed end up (p < 0.001). Some significant interactions occurred among all internal egg quality traits which were mostly dependent on the eggs stored horizontally, extended storage time more than 21 days and egg turning during storage. The results and interactions showed that internal quality traits would be preserved well for the eggs stored less than 21 days with the position of pointed end up independent of turning. If the storage period was to exceed 21 days, the eggs should be positioned horizontally and turning should be applied to preserve the quality of chukar eggs.

• Asian-Australasian Journal of Animal Sciences
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• v.24 no.2
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• pp.279-284
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• 2011

The objective of this study was to evaluate the effects of storage temperature and time on the quality parameters of eggs from laying hens at peak production. A total of 576 eggs were obtained from Lohmann Light-Brown hens, which were collected 3 times when the hens were 26, 27, and 28 weeks old. The fresh eggs were collected and measured within 2 h of being laid. Samples of 48 eggs each were stored in chambers for 2, 5, or 10 d inside a refrigerator ($5^{\circ}C$), at room temperature ($21^{\circ}C$), and at a high temperature ($29^{\circ}C$). As the storage temperature and time increased, egg weight, percentage of albumen, Haugh unit (HU), and yolk color significantly (p<0.001) decreased. In addition, egg shell weight, shell percentage, and albumen weight significantly (p<0.001) decreased with storage time. Yolk weight, yolk percentage, and albumen pH significantly (p<0.001) increased with increasing storage temperature, and yolk pH significantly (p<0.001) increased with increasing storage time. When the storage temperature was increased to $29^{\circ}C$, egg weight loss dramatically increased from 1.74 to 3.67% at 5 and 10 d of storage time, respectively. With the exception of the $5^{\circ}C$ storage temperature, HU dramatically decreased according to storage time and temperature, decreasing from 91.3 to 72.63 at $21^{\circ}C$ and from 87.62 to 60.92 at $29^{\circ}C$ during 10 d of storage; however, this decline was not found at $5^{\circ}C$. A rapid increase in albumen alkalinity was observed even after just 2 d of storage regardless of the storage temperature. Interactions between storage time and temperature were significant (p<0.001) with respect to egg weight loss, egg shell weight and percentage, albumen weight and percentage, yolk weight and percentage, albumen and yolk pH, HU, and yolk color. The results of the current study indicated that eggs from laying hens at peak production had significant deterioration of internal quality with increasing storage temperature and time. The results suggest that egg weight loss, albumen pH, and HU are parameters that are greatly influenced by the storage temperature and time of eggs from hens at peak laying.

• Korean Journal of Poultry Science
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• v.16 no.4
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• pp.233-238
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• 1989

This experiment was carried out to establish effective egg storage technology by studying the physico-chemical properties of albumen and yolk during the cold storage. The results obtained were summarized as follows：1. Egg Yolk was gelated and whipping quality and whipping stability of albumen was decreased by the freezing storage. 2. NaCl was the best anti-freezer to prevent the gelation of egg yolk among various anti-freezer (NaCl, glucose, sucrose, amides). 3. Viscosity of egg yolk and albumen was increased and color was changed but changes of colorin albumen was slight during the storage at $-5^{\circ}C$ and $-20^{\circ}C$. 4. To store the 5% NaC1 added egg yolk -at $-5^{\circ}C$ was the best way to prevent the gelation of egg yolk and save the energy. 5. Emulsion capacity of egg yolk was decreased by the cold storage with the addition of NaCl.