• 한국축산식품학회지
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• 제44권1호
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• pp.74-86
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• 2024

Eggs that have been hard-boiled are frequently used as ready-to-eat food. Refrigerated and frozen storage of hard-boiled eggs causes issues, such as customer rejection owing to textural changes. The objective of this research is to ascertain how storage temperature affects hard-boiled eggs' alteration in texture over time. Medium-sized brown shell eggs were acquired from a local market, boiled at 100℃ for 15 min, and then stored at room temperature (25℃), refrigeration (4℃), and freezing (-18℃) conditions for 0, 12, 24, and 48 h. Fourier transform infrared spectroscopy (FTIR), texture profile, visual observation using a gemological microscope, free amino acid content, and color were measured. Freezing had a substantial impact on the eggs' hardness, gumminess, chewiness, and cohesiveness (p<0.05). The FTIR spectrums confirmed the textural changes in bonds of amide A (3,271 cm^-1), amide I (1,626.2 cm^-1), amide II (1,539.0 cm^-1), C=O stretch of COO^- (1,397 cm^-1), asymmetric PO₂^- stretch (1,240 cm^-1). Microscopic images confirmed structural changes in eggs stored at -18℃. The free amino acid content was lower in fresh and frozen eggs than in the rest (p<0.05). However, there was no discernible variation in the egg white's color when eggs were kept at 4℃ (p>0.05). Salmonella spp. was found exclusively in eggs kept at room temperature. In conclusion, hard-boiled eggs did not exhibit structural or chemical changes when stored at 4℃ for up to 48 h compared to freezing and room temperature conditions.

• 한국식품영양과학회지
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• 제15권3호
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• pp.306-312
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• 1986

Demonstration of the highly positive correlation between blood cholestrol levels and heart disease has made consumers wary of the fats in meat, milk and eggs. The egg, as perhaps the single largest common source of cholesterol, has been cited by many members of the medical and scientific world as a food contributing to heart disease. In light of decreasing per capita egg consumption and continuing dietary egg cholesterol controversy, many researchers have focused their efforts on egg nutrition. The results reported, however, are often contradictory. In spite of the disputable scientific evidence, the egg has been labelled (erroneously) as a highly cholesterogenic food. The objective of this presentation is to present a general picture of the problem and discuss our laboratory findings relevant to the problem. An isotope technique was utilized to incorporate $^{14}C$-cholesterol into egg yolk lipoproteins and study the metabolic fate of dietary ovo-cholesterol in rats. Two hundred and fifty micro-curies of 4-$^{14}C$-cholesterol, emulsified in corn oil, were orally administered to five Single Comb White Leghorn laying hens. Eggs were collected, hard-boiled, and the hot dried egg yolk powder (HEY) was prepared. Total radioactivity excreted via feces was determined. The rat groups fed egg yolk powder excreted more than 95% of the ingested ovo-cholesterol, whereas the rat chow group excreted only 47%. No difference was observed between HEY and CEY treatments. Therefore, an unknown lipid factor present in egg folk accelerates cholesterol turnover rate and excretion via feces.

• 한국가금학회지
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• 제20권3호
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• pp.125-131
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• 1993

본 시험은 계란의 껍질을 파괴하지 않고 적절한 압력을 이용하여 적절한 농도의 염지액이 단시간 내에 계란의 난백 및 난황층으로 이동되어 염분이 가미된 계란을 제조한 다음 이를 열처리 과정을 거쳐서 반숙 또는 완숙된 계란으로 제조하거나 또는 열처리하지 않은 가염된 생계란을 제조하여 편리하게 식용할 수 있는 계란의 가미 가공방법에 관한 것이다. 염지계란의 염도에 영향을 주는 요소는 염지액 농도(0~40%, wt/vol), 염지시간(O~45h), 그리고 염지압력(O~4.5kg/$\textrm{cm}^2$) 등으로 이들 조건에 따른 계란의 소금 험하였다. 계란의 소금농도는 염지액농도, 염지시산, 염지압력에 비례하여 증가하는 경향을 보였으며 처리구 중 난백내에서 0.70~l.00%, 그리고 난황내에서 0.40~0.45%가 가장 바람직한 염농도임을 알 수 있었다. 한편 염지계란의 품질을 측정하기 위한 관능검사는 염지액농도(20~40%) 염지시간(12~20h), 그리고 염지압력(3~4.5kg/$\textrm{cm}^2$)에서 가장 우수한 결과를 보였다. 위 시험의 결과, 염지계란을 제조하는 조건으로 염지액농도 30%, 염지시간 16h 그리고 염지압력 4.0kg/$\textrm{cm}^2$에서 가장 우수한 결과를 보였다.

• 한국식생활문화학회지
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• 제26권5호
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• pp.455-467
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• 2011

The main purpose of this study was to survey the various kinds of recipes for pheasant found in seventeen Korean cookbooks published from the 1800's to the 1990's. There were 95 pheasant recipes found in the literature which could be classified into three major groups: cooking with moist heat, cooking with dry heat, and other. The three major groups were then broken down into thirteen smaller groups. A detailed look at the frequency of terms in each recipe shows that Gui Sanjeok (grilled Korean shish kebabs) appears 24 times, Guk Tang and Jeongol (soup and stew) 23 times, Kimchi (fermented cabbage) 11 times, Po (jerky) 9 times, Jorim (boiled in soy sauce) 7 times, Jjim (steamed) 6 times, Bokeum (stir-fried) 5 times, Twigim (deep-fried) 3 times, Buchim (fried) 2 times, Jigae jijim (stewed) 2 times, and Jang (paste), Myeon (noodles), Gooum (boiled) and Yeot (Korean hard taffy) 1 time each. The main ingredient is always the pheasant. We investigated the use of the whole pheasant cooked, how to slice and tenderize pheasant meat, use the meat only, or use only certain parts. Depending on the characteristics of cooking recipes, pheasants with thin, soft bones and organs were investigated for cooking. Substituted materials were used for a few of the vegetables, meat, and seafood in the recipes, and seem to go well together. Garnishes used included pine nut powder and fried eggs. Seasoned salt, soy sauce, pepper, sesame, sesame oil, chopped onion, garlic, and ginger were also reported to have been used.

• Asian-Australasian Journal of Animal Sciences
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• 제16권4호
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• pp.565-569
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• 2003

The objective of this experiment was to determine the effects of different levels of refined cod liver oil (RCLO) on laying performance, n-3 polyunsaturated fatty acids composition (n-3 PUFAs) and the organoleptic evaluation of duck egg yolks. A total of 180 30 wk old laying Tsaiya ducks, at the beginning of peak production, were allotted into 6 treatments with 3 replicates each. Ducks were fed one of the 6 experimental diets, supplemented with 2% tallow (control) and graded levels of RCLO at 2, 3, 4, 5, and 6% to a corn-soybean diets, respectively, for 6 wks. All of the experimental diets were formulated to be both isocaloric and isonitrogenous. Feed and water were supplied ad libitum throughout the experimental period. The results indicated that the RCLO supplementation levels did not affect (p>0.05) egg production, egg mass, feed intake, feed efficiency or body weight change. Egg weight was the lightest when the ducks received the 6% RCLO diet. The eicosapentaenoic acid, docosahexaenoic acid, and total n-3 PUFAs contents in the yolks increased with increasing RCLO supplementation. The taste and general acceptability of the hard-boiled eggs were not significantly different among the treatments. However, a fishy flavor was much higher when ducks were fed diets supplemented with 5% and 6% RCLO diets.

• 대한영양사협회학술지
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• 제11권3호
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• pp.320-330
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• 2005

The purpose of the study was to assess students’preferences on vegetarian menus served at middle and high schools. Four school food service programs that served primarily vegetarian menus were located in Seoul, Kyunggi, Kangwon, and Choongnam provinces. A total of 100 menu items frequently served at the schools were identified. Students participating in the school meals programs were asked to assess their preferences of the menus using a 5-point Likert-type scale(1 : very dislike - 5 : very like). Excluding responses with significant missing data, usable responses were 659. Statistical analyses were performed with descriptive statistics, t-tests, and one-way analysis of variance. Menu items of the highest preference scores included kimchi stew, stir-fried kimchi, nangmyon(cold noodles), fried rice and kimchi, miso stew, soft tofu stew, and hard-boiled quail eggs in soy sauce. By menu category, one-dish foods(3.97) were the most preferred and muchim and namul were the least preferred. Female students showed higher preferences on kimchi, steamed items(jjim), stir-fried items, namul, and muchim than male students; middle school students’preference scores were higher than those of the high school students in most menu categories. The menu preference is known as one of the most important factors determining students’food consumption and satisfaction with school food service. Dietitians working at school food service programs that serve primarily vegetarian menus should provide students with nutrition education on proper food selection and focus their efforts on developing new recipes using various vegetables and preparation methods to improve students’food consumption and menu preference.