• Korean Journal of Poultry Science
• /
• v.25 no.1
• /
• pp.21-30
• /
• 1998

The effects of dietary levels and feeding period of Korean hot pepper (Capsicum annum) seed on the performance and egg quality were investigated. Rhode Island Red layers of 84 wk of age were fed the experimental diets containing O.O(Control), 0.5, 1.0, 2.0, and 3.0% of HPS, respectively, in individual cages during 10 wk of the feeding period. The dietary hot pepper seed significantly(P<0.05) improved hen-day egg production and daily egg rnass, but reduced egg weight(P<0.05). During the 10 wk of the feeding period, the egg production and daily egg mass improved after 6 or 7 wk of feeding 0.5, 1.0 or 2.0% hot pepper seed diets. When the layers were fed the 3.0% HPS diet, it only took 1 wk to improve the egg production and daily egg mass. In addition, the birds fed 3.0% hot pepper seed diet showed relatively constant egg weight while those of the Control increased gradually as the feeding period passed. The dietary hot pepper seed significantly improved the eggshell thickness, and redness and whole color of egg yolk. The results indicate that dietary hot pepper seed( $\geq$2.0%) may improve the egg production and egg shell thickness, and increase the redness of egg yolk in layers.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.26 no.5
• /
• pp.860-865
• /
• 1997

Investigations were performed on the effects of extraction temperature, pressure, time on solubility and selectivity of egg yolk lipid and cholesterol, and color and fatty acid composition of the residue in supercritical carbon dioxide(SC-Co$_2$) extraction. Lipid and cholesterol solubility increased as the increase of Co$_2$ density and was found to strongly depend on the extraction pressure rather than the extraction temperature. The relative concentration of cholesterol in the extract increased with an increase in temperature and decreased with an increase in pressure and extraction time. extraction of dried eg yolk for 3hr at 4$0^{\circ}C$/276 bar removed 46.1% of cholesterol from the residual egg yolk with a yield of 63.2%. SC-Co$_2$ extraction produced a lighter color egg yolk with less redness and yellowness. As the extraction time increased, the resultant residual egg yolk became more saturated with fatty acids. SC-$CO_2$ extraction offers a safe, natural method for removing cholesterol from dried egg yolk.

• Korean journal of food and cookery science
• /
• v.17 no.1
• /
• pp.7-12
• /
• 2001

Yackwa was prepared by different amounts of egg yolk and then instrumental characteristics and sensory evaluation were investigated during storage periods. In texture profile analysis, hardness, gumminess and chewiness of Yackwa were increased during storage and texture parameters were increased by increasing egg yolk level. In Hunter's color value, lightness and redness were increased by increment of egg yolk level, whereas. yellowness was increased in negative region. During storage all values were increased. In the results of sensory evaluation, crispiness and overall acceptance were significantly different during storage and other parameters didn't showed significant difference among samples. The results showed that Yackwa prepared with 20g of egg yolk had good sensory quality and nutritious improvement.

• Korean Journal of Poultry Science
• /
• v.31 no.2
• /
• pp.79-84
• /
• 2004

A total of 225 ISA Brown layers, 63-wk-old, were used in a 5-wk feeding trial to measure the effect of dietary canthaxanthin(0, 50, 100, 200, and 300mg/kg feed) on its accumulation in various body parts and the egg yolk. There were three replications per treatment and 15 birds per replication. The redness(a$\^$*/) and yellowness(b$\^$*/) of wing and thigh skin significantly(P＜0.05) increased when canthaxanthin was fed at 2200 and 250mg/kg feed, respectively. However, the color of breast skin was not significantly affected by the canthaxanthin supplementation. Skin lightness(L$\^$*/) was not influenced by the dietary canthaxanthin. The dietary canthaxanthin supplementation did not significantly affect the redness or the yellowness of breast and thigh muscles. However, feeding canthaxanthin at 300mg/kg, compared to the control(0mg/kg feed), significantly(P＜0.05) decreased the lightness of wing and breast muscles. Feeding of canthaxanthin for 1-3d also significantly increased the color of egg yolks. In conclusion, canthaxanthin can be used to improve the color of skin and egg yolks, but it should be used cautiously because too intense egg yolk redness could be rejected by consumers.

• Journal of Environmental Health Sciences
• /
• v.41 no.6
• /
• pp.438-448
• /
• 2015

Objectives: This study was performed to examine the effects of storage time and temperature and their interaction on the hygienic quality parameters of shell eggs. Methods: Eggs from 40-week-old Hy-Line Brown hens were sampled immediately after being laid and subjected to storage periods of four weeks at a refrigerated temperature ($4-5^{\circ}C$) or room temperature ($13.0-19.7^{\circ}C$). Interior/exterior qualities were examined every one week. Results: Weight loss was 2.4-3.1%. The initial specific gravity of the eggs was maintained until one week at both temperatures. Air cell size exceeded 4 mm when stored for one week at room temperature, and two weeks at refrigerated temperature. Albumen index and Haugh unit were significantly decreased at both temperatures after one week (p<0.001). Rapidly increased pH of the albumen with one week of storage was observed, regardless of temperature (p<0.001). Extension of the storage for up to four weeks at room temperature resulted in remarkable deterioration of eggshell quality and instrumental color as redness (a). Air cell size, albumen and yolk indices, Haugh unit, pH of albumen and yolk were found to be influenced by storage time and temperature (p<0.001). Interaction effects between storage time and temperature were also significant for air cell size, pH of albumen and yolk (p<0.001). Conclusion: The results suggest that air cell size and pH of albumen and yolk were important parameters influenced by storage time and temperature in shell eggs. Storage time was more influential for air cell size, and temperature for the pH of yolk. Both variables almost equally influenced the pH of albumen.

• Asian-Australasian Journal of Animal Sciences
• /
• v.28 no.6
• /
• pp.840-846
• /
• 2015

The objective of this study was to investigate the effects of dietary corticosterone on egg quality. For 2 weeks hens received either control or experimental diet containing corticosterone at 30 mg/kg diet. Feed intake and egg production were monitored daily, and body weight measured weekly. Egg weights and egg quality were measured daily. Corticosterone treatment resulted in a remarkable increase in feed intake and sharp decrease in egg production compared with control (p<0.05) whereas body weight remained unchanged. Decreased albumen height, but no changes in egg weight, led to decreased Haugh unit (p<0.05). Corticosterone caused elevated eggshell thickness (p<0.05) without altering weight and strength, suggesting possible changes in shell structure. Yolk color and redness were increased by corticosterone (p<0.05) but lightness and yellowness were either not changed or inconsistent over the time period of measurements. Increased concentrations in plasma were also found for corticosterone, glucose, cholesterol, creatinine, uric acid, albumin, aspartate aminotransferase, creatine kinase, lactate dehydrogenase, total protein, and amylase (p<0.05), suggesting that corticosterone increased protein breakdown, renal dysfunctions and pancreatitis. Together, the current results imply that dietary corticosterone affects egg quality such as yolk colors and shell thickness, in addition to its effects on feed intake and egg production.

• Korean Journal of Poultry Science
• /
• v.31 no.2
• /
• pp.73-78
• /
• 2004

The effect of supplemental yellow ${\beta}$-8-Apo-carotenoic acid ethyl ester (ACA) (0~300mg/kg feed) on its accumulation in each body part of laying hens and the pigmentation in egg yolk was determined. The chickens used in this study were 78-wk-old ISA brown laying hens. ACA significantly affected the color of the bodies of laying hens. The yellowness ($b^*$) but not the redness ($a^*$) and, the lightness ($L^*$) of the skin, and muscle as measured by a colorimeter significantly (P < 0.05) increased when ACA was fed at 50~100 mg/kg feed. Egg yolk color was also significantly affected by feeding ACA longer than 2 days (P < 0.05) at the levels higher than 50 mg/kg feed. Conclusively, ACA is recommended for improving yellowness of skin.

• Culinary science and hospitality research
• /
• v.20 no.1
• /
• pp.65-75
• /
• 2014

This study prepared steamed eggs at various ratios of yolk and white in packaged liquid eggs to investigate the quality characteristics of steamed eggs through sensory tests and analyses of water content, color, pH and texture profiles. The results are expected to be used in developing steamed egg products and preparing processed egg dishes. Moisture contents of steamed egg samples increased with increased percentage of egg white. Hunter color values of L(lightness) also increased with increased percentage of egg white, while a(redness) and b(yellowness) decreased. Moreover, pH increased with increased percentage of egg white. Texture profile analyses in hardness, springiness, chewiness, gumminess, and cohesiveness decreased significantly with increased percentage of white, but adhesiveness was not significantly different. As the results of sensory test, yellowness increased with increased percentage of yolk. Roasted nutty smell was highest in the steamed egg sample prepared with 250g yolk and 200g white, and fishy smell increased and boiled egg smell decreased with increased percentage of white. Roasted nutty taste and fishy taste increased with increased percentage of white. In contrast with brittleness, hardness, springiness, and chewiness decreased with increased percentage of egg white. The acceptance score was high in the steamed egg samples prepared with a ratio of egg yolk 250/egg white 200 or egg yolk 150/egg white 300.

• Journal of Animal Science and Technology
• /
• v.45 no.5
• /
• pp.847-856
• /
• 2003

This study was carried out to investigate the effects of dietary xanthophylls supplementation on pigmentation and antioxidant properties in the egg yolk. ISA Brown laying hens aged 50 weeks were fed five kinds of xanthophyll combination such as control(neither natural nor artificial xanthophylls in feed), T1(Commercial diet containing natural xanthopylls in grain + Lutein 10ppm + Capsantin 10ppm), T2(T1 + Capsanthin 65ppm), T3(T1 + Canthaxanthin 65ppm), T4(T1 + Capsanthin 10ppm + Canthaxanthin 65ppm), and T5(T1 + Capsanthin 65ppm + Canthaxanthin 10ppm). The pH values of all egg yolks were not significantly different during storage or feeding periods. CIE L$^{*}$(lightness) values of T2 ~ T5 egg yolks were lower than those of control and T1. Conversely, the CIE a$^{*}$(redness) value of T2 ~ T5 egg yolks showed significantly higher(P<0.05). Egg yolk from chicks fed xanthophylls increased CIE b$^{*}$ values. The CIE b$^{*}$(yellowness) values of T2 ~ T5 egg yolks were higher than control and T1 during storage at 37$^{\circ}C$ for 48 hours respectively. In the antioxidation experiment, dietary xanthophylls supplementation affected lipid antioxidation of egg yolk during storage. The TBARS(O.D.) of egg yolks from chicks fed xanthophylls were lower than that of control during incubation at 37$^{\circ}C$ for 10 hours. In conclusion, dietary xanthophylls supplementation influence to color difference and retardation of lipid oxidation in egg yolk.

• Korean Journal of Veterinary Research
• /
• v.36 no.2
• /
• pp.463-470
• /
• 1996

The red yeast Phaffia rhodozyma, which contains astaxanthin(3, 3'-dihydroxy-$\beta$, $\beta$-carotene-4, 4'-dione) as its primary carotenoid, was tested as a dietary pigment source for egg yolks of laying hens. When the yeast was fed to laying hens at several concentrations, the intensity of redness in egg yolks was dependent on the yeast concentration in the feed and the deposition period. Addition of P rhodozyma in feed did not cause any visible adverse effect on laying hens.