• Asian-Australasian Journal of Animal Sciences
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• v.12 no.2
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• pp.192-196
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• 1999

The purpose of this experiment was to study the effects of feeding egg yolk prepared from quail fed winged bean oil on plasma and liver cholesterol and fatty acids composition in rats. Eggs were collected from laying quails that had been fed diets containing 5% of either animal tallow, soybean oil, corn oil or winged bean oil. Yolk powders (referred to as winged bean yolk, soybean yolk, etc.) were prepared and fed at the 15% level to weanling female Wistar rats for 28 days. Rats fed winged bean yolk had significantly lower body weight gain than did rats fed soybean yolk or animal tallow yolk. There are no significant effects on plasma total cholesterol, liver cholesterol and triglyceride concentration due to feeding yolk powder containing different oil. However, LDL-cholesterol increased and HDL-cholesterol decreased in rats fed winged bean yolk. Liver lipid of rats fed with winged bean yolk had a higher linoleic but a lower linolenic content than did those fed animal tallow yolk. However, rats fed with winged bean yolk had a lower linoleic content than did rats fed soybean yolk or corn yolk. In conclusion, winged bean yolk seemed to have had an adverse effect on rats.

• Korean Journal of Ichthyology
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• v.8 no.1
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• pp.49-55
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• 1996

The growth of total length(TL), total weight(TW) and somatic weight(SW) of rainbow trout, Oncorhynchus mykiss alevin at yolk absorption period was expressed by the Gompertz growth model as $TLt=2.7e^{-1.24{\cdot}e^{-0.11t}}(r^{2}=0.66)$, $TWt=1.8e^{-2.03{\cdot}e^{-0.11t}}(r^{2}=0.66)$ and $SWt=1.8e^{-5.41{\cdot}e^{-0.13t}}(r^{2}=0.83)$ respectively. Yolk length, yolk height and yolk volume of rainbow trout decreased linearly. The relative growth of total weight-total length, somatic weight-total length, yolk length-total length, yolk height-total length, yolk volume-total length, yolk weight-total length, yolk weight-total weight, yolk weight-yolk height and yolk weight-yolk length at yolk absorption period revealed the pattern of yolk absorption in rainbow trout.

• 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 the East Asian Society of Dietary Life
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• v.20 no.1
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• pp.77-83
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• 2010

The study was conducted to investigate the effect of particle size on the physicochemical properties of egg yolk-rice porridge. The pH of egg yolk-rice porridge was decreased when compared to that of the control, while the lightness and yellowness was increased as the rice particle size increased. The viscosity of whole particle egg yolk porridge was highest among the three porridges at $40^{\circ}C$. The protein content of the egg yolk-rice porridge was increased three-fold, when compared to that of the rice porridges. The total amino acid content of egg yolk-rice porridge was 1,500.6 mg/100 g, while that of rice was 1,147.5 mg/100 g. The Lys and Thr content of the amino acid content of egg yolk-rice porridge were also increased. Sensory evaluation results revealed that the half particle size rice egg yolk-rice porridge had the highest scores in color, taste and over-all preference. Based on these results, the half particle size egg yolk-porridge had good quality with respect to both the physicochemical and nutritional properties.

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

• Food Science and Biotechnology
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• v.14 no.6
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• pp.793-797
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• 2005

Optimum conditions for cholesterol removal in egg yolk were evaluated based on ratio of egg yolk-to-water, crosslinked ${\beta}$-cyclodextrin (${\beta}$-CD) concentration, and mixing temperature, time, and speed by adding crosslinked ${\beta}$-CD treated with adipic acid. Cholesterol removal in egg yolk-water mixture increased with increasing ${\beta}$-CD level (10-25%). About 95% was removed by 25% ${\beta}$-CD at 1:1 ratio of egg yolk-to-water and 800 rpm mixing at $40^{\circ}C$ for 30 min. In recycling study, removal rates were measured using ten times recycled crosslinked ${\beta}$-CD in egg yolk, and 85% cholesterol removal was observed with eight times reuse. These results indicated that over 90% cholesterol was removed at 1:1 ratio of egg yolk-to-water, 20% crosslinked ${\beta}$-CD addition, and 30 min mixing with 600 rpm at $40^{\circ}C$.

• Korean Journal of Animal Reproduction
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• v.20 no.2
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• pp.101-109
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• 1996

This study was done to find out the methods of long-term use of liquid boar semen in 100 ml plastic bottle for artificial insemination and to investigate differences between Lactose-Egg yolk and Biitschwiler diluents according to storage temperature, and effect of final glycerol concent ration in Lactose-Egg yolk diluent. Liquid boar semen diluted with Lactose-Egg yolk diluent showed significantly higher sperm motility (p<0.05) after 0.5 and 2h incubation at 37$^{\circ}C$,than Butschwiler diluent at all storage length when it was preserved in the 5$^{\circ}C$ refrigerator. The NAR acrosome in Lactose-Egg yolk diluent a after 0.5 and 2h incubation at 37$^{\circ}C$, respectively, during preservation periods was similar to that in Biitschwiler diluent. When liquid boar semen was preserved at 15$^{\circ}C$, liquid boar semen in the Butschwiler diluent showed significantly higher percentages of sperm motility and NAR acrosome from third day to seventh than that in Lactose-Egg yolk diluent. In the effect of final glycerol concentration of liquid boar semen in the Lactose-Egg yolk diluent, the final glycerol concentration of 2% showed higer percentages of sperm motility and NAR acrosome than that of 0, 1, 3, and 5%. Farrowing rate, litter size and average pig weight at birth did not differ significantly between Lactose-Egg yolk and But schwiler diluents. As a result of this study, we found out that liquid boar semen can be stored for 6-7 days at 5$^{\circ}C$ in Lactose-Egg yolk diluent and at 15$^{\circ}C$ in Butschwiler diluent.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.1
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• pp.158-163
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• 2004

We investigated the usefulness of 2-alkylcyclobutanones as markers for irradiated eggs and egg products by comparing 2-alkylcyclobutanone concentrations in irradiated raw egg yolk, boiled egg yolk, and egg yolk powder. One method of detection radiation-induced 2-alkylcyclobutanones involves extraction fat from irradiated egg samples separating 2-alkylcyclobutanones by florisil column chromatography, and identifying GC/MS. 2-(5'-Tetradecenyl)cyclobutanone of 2-alkylcyclobutanones was high relatively in boiled egg yolk, but 2-dodecylcyclobutanone was high in raw egg yolk and egg yolk Powder. Concentrations of the radiation-induced 2-alkylcyclobutanones increased linearly with the irradiation dose. The radiation-induced 2-alkylcyclobutanones from egg samples at 0.5 kGy over and not detected at the non-irradiated samples. Therefore, these compounds could be used as marker of Post-irradiation for egg Products.

• Korean Journal of Food Science and Technology
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• v.34 no.3
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• pp.459-465
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• 2002

To obtain the basic data for commercial 10% salted egg yolk for mayonnaise preparation, 3 types of egg yolks [pasteurized egg yolk (Yolk A)-not salted, pasteurized before salting (Yolk B)-salted, and pasteurized after salting (Yolk C)-salted] were prepared, and the changes in quality characteristics of these egg yolks with frozen storage were tested. The results obtained were as follows; Yolk A gelatinized during frozen storage, thus could not used for mayonnaise preparation. The viscosity of the egg yolk increased $3{\sim}5$ times after salting. Viscosity of the salted egg yolk increased with frozen storage time. Viscosity of Yolk B was higher at $-20^{\circ}C$ than $-15^{\circ}C$. Viscosity of Yolk C, however, was higher at $-15^{\circ}C$ than $-20^{\circ}C$. Frozen storage of pasteurized salted egg yolk showed some effects on the emulsification capacity. The effect, however, was smaller than that of unpasteurized salted egg yolk. Microbes of salted egg yolk were decreased with frozen storage, but there was no difference between Yolk B and Yolk C. It was suggested that commercially pasteurized 10% salted egg yolk for mayonnaise preparation can be successfully stored for 12 months at the temperature of $-15{\sim}-20^{\circ}C$.

• Journal of Fisheries and Marine Sciences Education
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• v.28 no.5
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• pp.1231-1243
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• 2016

The ultrastructural study on oocyt development and the process of vitellogensis in the oocytes during oogenesis in female Pampus echinogaster were investigated by electron microscope observations. In the previtellogenic phase, in particular, several intermitochondrial cements appear in the cytoplasms of the chromatin nucleleolus oocyte and perinuclear oocyte. The number of intermitochondrial cements are associated with the multiplication of the number of mitochondria in the early developmental stage. In the early vitellogenic phase, the Golgi complex in the cytoplasm of the yolk vesicle oocyte is involved in the formation of yolk vesicles containing carbohydrate yolks. At this time, many pinocytotic vesicles containing yolk precursors (exogenous substances) by pinocytosis are observed in the cytoplasm near the region of initial formation of the zona pellucida. In the late vitellogenic phase, two morphological different bodies, which formed by the modified mitochondria, appeared remarkably in the yolked oocytes. The one is the multivesicular bodies and another is yolk precursors. The multivesicular bodies were transformed into the primary yolk globules, while yolk precursors were connected with exogeneous pinocytotic vesicles near the zona pellucida. After the pinocytotic vesicles were taken into yolk precursors, the yolk precursors were transformed into the primary yolk globules. Thereafter, primary yolk globules mixed with each other, eventually, they developed into secondary and tertiary yolk globules. In this study, vitellogenesis of this species occurred by way of endogenous autosynthesis and exogenous heteogenesis. Vitellogenesis occurred through the processes of endogeneous autosynthesis, involving the combined activity of the Golgi complex, mitochondria and multivesicular bodies formed by modified mitochondria. However, the process of heterosynthesis involved pinocytotic incorporation of extraovarian precursors (such as vitellogenin in the liver) into the zona pellucida (by way of granulosa cells and thecal cells) of vitellogenic oocytes.