• Journal of the Korean Applied Science and Technology
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• v.25 no.2
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• pp.196-204
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• 2008

Hemp seed oil and evening primrose oil were incorporated into the diets of laying hens for 5 weeks and the level of gamma fatty acid in the eggs that the treated hens laid was then evaluated. Hens were fed corn-soybean based diets that contained 5% tallow, 5% corn oil (CO), 5% hemp seed oil (HSO), or 5% evening primrose oil (EPO). The hemp seed oil and evening primrose oil influenced the amount of gamma linolenic acid found in the eggs through blood. The level of gamma linolenic acid in the plasma was significantly higher in hens that received the HSO and EPO diets than in those that received the tallow and CO diets. The HSO and EPO diets led to a 1.09% and 4.87% increase in egg gamma linolenic acids, respectively, when compared with eggs produced by hens treated with tallow and CO. Taken together, these data demonstrate that healthy eggs with increased gamma linolenic acids can be generated by minor diet modifications when hemp seed oil or evening primrose oil is included in the hen diet.

• Parasites, Hosts and Diseases
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• v.59 no.4
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• pp.393-397
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• 2021

Although research conducted in East Asia has uncovered parasite eggs from ancient toilets or cesspits, data accumulated to date needs to be supplemented by more archaeoparasitological studies. We examined a total of 21 soil samples from a toilet-like structure at the Hwajisan site, a Baekje-period royal villa, in present-day Korea. At least 4 species of helminth eggs, i.e., Trichuris trichiura, Ascaris lumbricoides, Clonorchis sinensis, and Trichuris sp. (or Trichuris vulpis) were detected in 3 sediment samples of the structure that was likely a toilet used by Baekje nobles. The eggs of T. trichiura were found in all 3 samples (no. 1, 4, and 5); and A. lumbricoides eggs were detected in 2 samples (no. 4 and 5). C. sinensis and T. vulpis-like eggs were found in no. 5 sample. From the findings of this study, we can suppose that the soil-transmitted helminths were prevalent in ancient Korean people, including the nobles of Baekje Kingdom during the 5th to 7th century.

• Food Science and Preservation
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• v.20 no.1
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• pp.69-75
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• 2013

This study was conducted to investigate the reliability of automatic cracked and bloody egg detector according to the age of the hens and the level of the detector. The results of this study are expected to be helpful in the implementation of the Korean egg grading system, which is expected to improve egg quality for consumers. An official egg grader randomly selected 1,000 eggs for each experiment (total 36,000 eggs), ran them through the automatic detector, and conducted labor inspection using the eggs that were classified by the detector as cracked, bloody, and normal eggs. The results showed that more cracked eggs were laid by hens aged 40-60 weeks than by hens aged 30 weeks (p<0.05). Also, when the detector level increased from four to seven (i.e., when it became less sensitive), its cracked eggs detection rate dropped, and the total rate of cracked eggs was consistent after the labor inspection of the classified eggs. The automatic detector achieved over 97 percent accuracy. The bloody eggs constituted only 0.005 percent of all the samples, and all the detector-detected eggs were bloody eggs after the labor inspection of both the bloody and normal egg lines. Therefore, it can be concluded that the automatic cracked and bloody egg detector was reliable and can be used in the egg grading system. Considering that cracked eggs should be less than 9 percent of first-grade eggs in the present egg grading system, the use of an automatic crack detector may help provide better-quality eggs to consumers by producing less than 5.5 percent cracked eggs.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.6
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• pp.375-380
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• 2017

This study assessed the technology to minimize the discoloration to reduce the defect rate and penetrate the curing solution through the egg shells to produce quality smoked eggs that meet the preference of consumers. The discoloration refers to the defects on the colors of egg shells due to overheated smoking fluids, causing the eggs to be discarded. The manufacturing process was prepared by the manufacturer of the regular smoked egg manufacturing process. A preliminary study found that the preferred salinity of smoked eggs was 1.67~2.00% and the major processing factors have been set to maintain the optimal salinity of smoked eggs and an industrially attainable minimum defect rate below 3%. When the eggs were aged at $50^{\circ}C$ for 96 hours to produce the smoked eggs, the discoloration rate was 0%. When the circulatory dipping method was applied, 3.00% salinity was achieved after 8 hours. When the eggs were smoked at that time, the salinity was 1.67%. With a $2.07kg/cm^2$ pressure, 3.33% salinity was achieved after 4 hours and 2.00% salinity was achieved when the smoked eggs were produced. To identify the most efficient pressurizing method, 0.52, 1.55, 1.86, 2.07, 2.38, 2.58, and $3.62kg/cm^2$ were applied, the discoloration rate was 2.2% after 4 hours under a $2.07kg/cm^2$ pressure. The aging and pressurized method is considered to be the basis for reducing the manufacturing time and decreasing the rate of error during the smoked eggs process.

• 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.

• Parasites, Hosts and Diseases
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• v.50 no.3
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• pp.243-247
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• 2012

Ascaris suum eggs are inactivated by composting conditions; however, it is difficult to find functional changes in heat-treated A. suum eggs. Here, unembryonated A. suum eggs were incubated at $20^{\circ}C$, $50^{\circ}C$, and $70^{\circ}C$ in vitro, and the gene expression levels related to viability, such as eukaryotic translation initiation factor 4E (IF4E), phosphofructokinase 1 (PFK1), and thioredoxin 1 (TRX1), and to apoptosis, such as apoptosis-inducing factor 1 (AIF1) and cell death protein 6 (CDP6), were evaluated by real-time quantitative RT-PCR. No prominent morphological alterations were noted in the eggs at $20^{\circ}C$ until day 10. In contrast, the eggs developed rapidly, and embryonated eggs and hatched larvae began to die, starting on day 2 at $50^{\circ}C$ and day 1 at $70^{\circ}C$. At $20^{\circ}C$, IF4E, PFK1, and TRX1 mRNA expression was significantly increased from days 2-4; however, AIF1 and CDP6 mRNA expression was not changed significantly. IF4E, PFK1, and TRX1 mRNA expression was markedly decreased from day 2 at $50^{\circ}C$ and $70^{\circ}C$, whereas AIF1 and CDP6 mRNA expression was significantly increased. The expressions of HSP70 and HSP90 were detected for 9-10 days at $20^{\circ}C$, for 3-5 days at $50^{\circ}C$, and for 2 days at $70^{\circ}C$. Taken together, incremental heat increases were associated with the rapid development of A. suum eggs, decreased expression of genes related to viability, and earlier expression of apoptosis-related genes, and finally these changes of viability- and apoptosis-related genes of A. suum eggs were associated with survival of the eggs under temperature stress.

• Korean Journal of Ichthyology
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• v.28 no.4
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• pp.229-238
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• 2016

This study aims to investigate egg quality and amino acid composition of buoyant and non-buoyant eggs and evaluate egg quality of sevenband grouper, Epinephelus septemfasciatus. Amino acid analysis of eggs was conducted to investigate what elements were necessary for the survival and good quality of egg depending on farming condition and different diet. We analyzed amino acid from buoyant eggs and non-buoyant eggs, farming conditions (tank and sea cage), and different dietary conditions (formulated feed, formulated feed+raw fish-based moist pellets, and raw fish-based moist pellets). Egg quality was the best in a sea cage and when raw fish-based moist pellets (MP) were fed. In addition, egg quality with formulated and MP was better than that with formulated feed. As a result of amino acid analysis of eggs, buoyant eggs were containing more free amino acid than non-buoyant eggs. Also, eggs with MP were containing more free amino acid than those with formulated feed and MP. Eggs with mixed formulated feed and MP were containing more free amino acid than formulated feed. In conclusion, amino acid was helpful to improve egg quality, and egg quality can be controlled by farming conditions and feed.

• Korean Journal of Poultry Science
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• v.20 no.4
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• pp.217-231
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• 1993

Due to the increased awareness on the relationship between high cholesterol intake and cardiovascular disease, the development of low cholesterol eggs and egg products are necessary at the present time. Largely, two approaches are possible to develop low cholesterol eggs. The first approach is the production of low cholesterol eggs by altering feeds of layers, by administering drugs, by genetic selection of strains and breeds, and by management of laying cycle, age and egg size. The second approach is to manufacture low cholesterol eggs technically treated with adsorbant, solvent, enzyme, edible oil and supercritical fluid. Both approaches have their own pros and cons, respectively, as far as the cholesterol removal rates, the easeness of process, and the economic reasons are concerned. The low cholesterol egg production is quite labor-intensive and has relatively low cholesterol removal rate(30∼50％ ) compared to that of chemically treated eggs. On the other hand, the low cholesterol eggs treated with chemicals have a very high cholesterol removal rate (80∼90％) but some of the methods are not completely safe as food processing purposes due to the residual chemicals and the sensory quality is not as good as the low cholesterol eggs without chemical treatment. Therefore, further studies must be conducted to improve the sensory quality of low cholesterol eggs and to eliminate fear about the harmfulness using low cholesterol eggs.

• Korean journal of applied entomology
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• v.57 no.4
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• pp.297-302
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• 2018

We surveyed branches of acacia trees distributed nationally in Korea to establish a common survey method that can be used by investigators to monitor for over-wintering Metcalfa pruinosa eggs. A total of 189 samples was examined, and the number of eggs on the surfaces of the branches, bases of thorns and bases of twigs was recored. When including samples in which no eggs were found at all investigation sites, none of the data followed the normal distribution. However, when samples in which no eggs were found at all sites were exclued, the density of eggs investigated at the thorn bases and twig bases followed the normal distribution. When the density of eggs was sorted based on the thickness of the branches on which they were found, these data did not follow the normal distribution. The density of M. pruinosa eggs at the thorn bases and twig bases was significantly higher than that on the branch surfaces, but there was no significant difference among branches of different thicknesses. Therefore, monitoring for M. pruinosa eggs at the thorn bases and twig bases of the nationally distributed acacia tree, irrespective of the thickness of the branches, will be able to increase the precision with which the density of this insect's eggs could be estimated. It is thus expected that this method will contribute to developing methods to better characterize the distribution and predict the occurrence of this.

• Korean Journal of Environmental Biology
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• v.41 no.2
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• pp.138-144
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• 2023

The main factor of biodiversity decline in major biological populations around the world is invasion of alien species. To protect native species, it is necessary to manage alien species. Recently, to eradicate ecosystem disturbance caused by alien species in Korea, many efforts have been made to capture individuals using nets and purchase captured individuals. However, there is no standard for classifying species due to the form of nest site or external characteristics of eggs of freshwater turtles. Thus, Mauremys reevesii eggs might be discarded due to mistaking as eggs of alien turtles. Based on more data, this study aims to compare and analyze external differences among eggs of Trachemys scripta elegans, Pseudemys concinna, and M. reevesii and use them as reference materials in the process of eradicating alien turtles. This study measured characteristics of eggs of the three turtle species. As a result of comparison, all variables of external characteristics of alien turtles and M. reevesii eggs showed significant differences. The shape of egg was also different, with eggs of T. scripta elegans and P. concinna showing a bicone shape and those of M. reevesii showing an ellipsoid shape. In conclusion, based on results of previous studies and the present study, eggs of M. reevesii, T. scripta elegans, and P. concinna are different in shape and structure. Thus, it is possible to distinguish between M. reevesii and invasive alien turtle using their eggs.