• Animal Bioscience
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• 제34권7호
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• pp.1193-1201
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• 2021

Objective: According to market demand, meat duck breeding mainly includes 2 breeding directions: lean Pekin duck (LPD) and fat Pekin duck (FPD). The aim of the present study was to compare carcass and meat quality traits between 2 strains, and to provide basic data for guidelines of processing and meat quality improvement. Methods: A total of 62 female Pekin ducks (32 LPDs and 30 FPDs) were slaughtered at the age of 42 days. The live body weight and carcass traits were measured and calculated. Physical properties of breast muscle were determined by texture analyzer and muscle fibers were measured by paraffin sections. The content of inosine monophosphate (IMP), intramuscular fat (IMF) and fatty acids composition were measured by high-performance liquid chromatography, Soxhlet extraction method and automated gas chromatography respectively. Results: The results showed that the bodyweight of LPDs was higher than that of FPDs. FPDs were significantly higher than LPDs in subcutaneous fat thickness, subcutaneous fat weight, subcutaneous fat percentage, abdominal fat percentage and abdominal fat shear force (p<0.01). LPDs were significantly higher than FPDs in breast muscle thickness, breast muscle weight, breast muscle rate and breast muscle shear force (p<0.01). The muscle fiber average area and fiber diameter of LPDs were significantly higher than those of FPDs (p<0.01). The muscle fiber density of LPDs was significantly lower than that of FPDs (p<0.01). The IMF of LPDs in the breast muscle was significantly higher than that in the FPDs (p<0.01). There was no significant difference between the 2 strains in IMP content (p>0.05). The polyunsaturated fatty acid content of LPDs was significantly higher than that of FPDs (p<0.01), and FPDs had higher saturated fatty acid and monounsaturated fatty acid levels (p<0.05). Conclusion: Long-term breeding work resulted in vast differences between the two strains Pekin ducks. This study provides a reference for differences between LPD and FPD that manifest as a result of long-term selection.

• Asian-Australasian Journal of Animal Sciences
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• 제30권6호
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• pp.872-877
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• 2017

Objective: In order to utilize fat from broiler byproducts efficiently, it is necessary to develop an appropriate rendering procedure and establish quality information for the rendered fat. A study was therefore undertaken to evaluate the influence of rendering methods on the amounts and general properties of the fat recovered from broiler skin. Methods: The yield and quality of the broiler skin fat rendered through high and lower energy microwave rendering (3.6 W/g for 10 min and 2.4 W/g for 10 min for high power microwave rendering (HPMR) and high power microwave rendering (LPMR), respectively), oven baking (OB, at $180^{\circ}C$ for 40 min), and water cooking (WC, boiling for 40 min) were compared. Results: Microwave-rendered skin exhibited the highest yields and fat recovery rates, followed by OB, and WC fats (p<0.05). HPMR fat had the highest $L^{\star}$, $a^{\star}$, and $b^{\star}$ values, whereas WC fat had the highest moisture content, acid values, and thiobarbituric acid (TBA) values (p<0.05). There was no significant difference in the acid value, peroxide value, and TBA values between HPMR and LPMR fats. Conclusion: Microwave rendering at a power level of 3.6 W/g for 10 min is suggested base on the yield and quality of chicken fat.

• 한국식품영양과학회지
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• 제19권1호
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• pp.1-12
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• 1990

To investigate effects of ethanol and dietary fat on growth and bichemical indices of liver tissue and blood in rats 40 male rats of Sprague-Dawley wtrain weighing about 160g were divided into 5 groups (low-fat diet group ethanol-administered low-fat diet group high-fat diet group ethanol-administered high-fat diet group and commercial diet group) and fed expe-rimental diets for 8 weeks. Ethanol-administered groups consumed ethanol corresponding to 22 cal% which was considered as moderate drinking. Neither the ethanol intake nor the dietary fat level affected calorie intake. Nonetheless the low-fat diet group with ethanol had the lowest growth rate and 2-fold increase in the concentration of plasma triglyceride. There was no effect of ethanol and dietary fat level on contents of protein lipid and lipid composition of liver tissue. The level of lipid peroxide of liver tissue tended to be increased by ethanol intake but the increase was statistically insignificatnt. The low-fat ethanol group had lowered hepatic mitochondrial respiration rate and deformed structure of mitochondria of hepatocytes.

• Preventive Nutrition and Food Science
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• 제4권3호
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• pp.184-187
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• 1999

Increase in fat mobilization by capsaicin(CAP) was investigated in high-fat-fed mice using an adjustable current water pool. Male ICR 7-wk-old mice were fed a high fat diet [50% total energy content in the diet(E%) fat, 20 E% protein, 30E% carbohydrate] for 2 wk and one group (HCAP) was orally administered CAP at 2 h before swimming. After being accustomed to swimming , the mice were subjected to forced swimming every 2d in the current water pol and the total swimming period until exhaustion was measured . The total swimming period was used as index of swimming capacity. Swimming time to exhaustion of treated mice was significantly longer than that of the high-fat-fed control group (100.2$\pm$10.6 vs. 58.0$\pm$8.5min, P<0.01) after 2wk of training. The concentration of serum-free fatty scids gradually increased up to 2 h in CAP -administered mice. The perirenal adipose tissue weight of CAP -administered mice (HCAP) before swimming was lower than that of the high-fat-fed mice adminstered placebo solution (HP) which had not ingested CAP during the 2 wk. These results suggest that the increase of swimming capacity of CAP-administered high-fat-fed mice was due to an increase of fat mobilization that was induced by CAP.

• 동아시아식생활학회지
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• 제18권2호
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• pp.181-189
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• 2008

In this study, changes in total trans fatty acid (tFA) and fat contents were determined in soybean oil, shortening, and olive oil after potato sticks were fried 30 consecutive times, respectively. Prior to frying, the potato sticks contained 3.8% fat, with 43.2% tFAs, After the first frying in soybean oil, the total tFA content of the potato sticks sharply decreased to 3.2%, and then it gradually increased to 8.1 % after 30 consecutive times of frying. However, the total fat content of the potato sticks, fried in soybean oil increased to 15.2% after the first frying and thereafter it decreased to 9.75% with 30 repeated episodes of frying. When the potato sticks were fried in olive oil, similar changes in tFA and fat contents were shown; while such changes were not observed when shortening was used. After 30 consecutive frying events, the tFA contents in the soybean oil and olive oil increased to 4.15 and 5.75%, respectively; however, such an increase was not observed in the shortening. One can assume that most of the tFAs in the fried oils were from the potato sticks, which contained relatively high tFA content during the repeated deep-frying process.

• Nutritional Sciences
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• 제1권1호
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• pp.34-41
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• 1998

This study examined the proper roles of dietitian and nurse-teacher in the weight control program (WCP) in schools and the effect of the WCP on subjects with respect to anthropometric measurements, nutrition knowledge, dietary attiude, and behavior changes. The program consisted of six sessions of nutrition education and frequent face-to-face nutrition counseling. Subjects were 22 obese children in the 4th and 5th grade who underwent counseling and 18 obese children in another school who served as a control group. After two months of WCP, obesity index such as .elative body weight (RBW, from 135.7 to 132.5), tricep skinfold thickness (TSFT, from 34.9 to 32.8 mm), and body fat content (from 32.0 to 29.8%) had decreased significantly in the experimental group, while the control group showed no significant differences in these indices. The reductions in obesity indices were maintained in the experimental group except for fat content (32.6%), which returned to its original value within six months. The control group significantly increased fat content in the same period (from 31.2% to 36.2%). Both groups decreased RBW, TSFT, and fat content while midarm circumference and waist/hip ratio remained the same after one year. Subjects' nutrition knowledge was improved with average test scores from 15.1 to 16.7 while nutrition attitude and behavior test scores remained unchanged suggesting that behavior modification may require more time than knowledge acquirement. These results suggest that proper nutrition counseling can initiate weight reduction. However, the maintenance of controlled weight requires changes in attitude and behavior which have not been achieved by the present WCP. The role of school dietitian for WCP in this study was limited to assisting the nurse-teacher in nutrition education. Expansion of dietitian's role in nutrition education and counseling is needed.

• Journal of Animal Science and Technology
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• 제56권2호
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• pp.5.1-5.5
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• 2014

The objectives of this study were thus to identify most significant factors that determine milk component yield (MCY) using a meta-analysis and, if possible, to develop equations to predict MCY using variables that can be easily measured in the field. A literature database was constructed based on the research articles published in the Journal of Dairy Science from Oct., 2007 till May, 2010. The database consisted of a total of 442 observed means for MCY from 118 studies. The candidate factors that determine MCY were those which can be routinely measured in the field (e.g. DMI, BW, dietary forage content, chemical composition of diets). Using a simple linear regression, the best equations for predicting milk fat yield(MFY) and milk protein yield (MPY) were $MFY=0.351({\pm}0.068)+0.038({\pm}0.003)$ DMI ($R^2=0.27$), and $MPY=0.552({\pm}0.071)+0.031({\pm}0.002)DMI-0.004({\pm}0.001)$ FpDM (%, forage as a percentage of dietary DM) ($R^2=0.38$), respectively. The best equation for predicting milk fat content (%) explained only 12% of variations in milk fat content, and none of a single variable can explain more than 5% of variations in milk protein content. We concluded that among the tested variables, DMI was the only significant factor that affects MFY and both DMI and FpDM significantly affect MPY. However, predictability of linear equations was relatively low. Further studies are needed to identify other variables that can predict milk component yield more accurately.

• 한국식품영양과학회지
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• 제36권8호
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• pp.1010-1014
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• 2007

대전 및 충청 지역에서 판매되고 있는 즉석식품의 조지방 및 트랜스지방산의 함량을 조사하고자 찹쌀도넛과 꽈배기 각각 6종, 고구마 스틱 2종, 토스트 9종, 그리고 멀티플렉스 극장 팝콘 11종 등 총 41종을 수거하여 분석하였다. 조지방 함량은 멀티플렉스 극장 팝콘 13.74${\sim}$38.09%로 가장 높았으며, 고구마 스틱 20.82${\sim}$20.88%, 오징어 튀긴 9.37${\sim}$25.53%등의 순이었다. 수거한 시료는 유탕처리 식품이었으며, 멀티플렉스 팝콘은 전자렌지용 팝콘과 달리 트랜스지방산 함량이 매우 적게 분석된 것으로 보아 식물성 부분 경화 유지를 상요하지 않은 것으로 보인다. 트랜스지방산 함량은 대부분 1 g(g/100 g food) 미만으로 낮았으나, 멀티플렉스 극장 팝콘 중 한 시료만이 3.08 g(g/100 g food)으로 높게 나타났다.

• 한국식품조리과학회지
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• 제1권1호
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• pp.57-64
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• 1985

This study was conducted to investigate the effect of fat on structure and texture of soybean curds by partial or whole replacement of soybean with defatted soy flour, The textural properties of soybean curd were examined by Instron universal testing machine, and the microscopic structure of soybean curds was examined by Scanning electron microscope(SEM). The results obtained were as follows ; 1. Textural parameters determined by Instron universal testing machine showed that hardness and gumminess of soybean curs were significantly increased as the fat contents of the samples decreased. On the while, springiness of the samples were significantly lowered as the fat content decreased. 2. Microscopic structure of soybean curds examined by SME demonstrated that samples with high fat had more fat globules and thinner network layer which were assumed to surround moisture with.

• Journal of Nutrition and Health
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• 제12권2호
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• pp.45-51
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• 1979

The present study was undertaken to determine the metabolic effect of various levels and kinds of fat in the diet. Body lipid metabolism at different period of rat's life was also studied by sacrificing rats and collecting samples initially, at second and fourth week of experimental period. Body weight, FER, PER were low in the group fed 30% fat diet. The weight of internal organ and epididymal fat pad was low in high fat diet group. The level of total serum cholesterol of rats in butter group showed higher than that of soybean oil group when the level of dietary fat content was same. The ratio of total cholesterol and total lipid in serum of rats in butter group appear to be higher than that of soybean oil group.