• Korean Journal of Poultry Science
• /
• 제14권1호
• /
• pp.39-53
• /
• 1987

A total of 1,440 White Leghorn pullets hatched in summer and winter, aged 20 to 72 weeks were fed 9 rations differing in dietary protein (13, 15 and 17%) and energy (2,500, 2,700 and 2,900 kcal/kg) levels for a period of 52 weeks in order to evaluate the optimum dietary energy and protein levels for laying hens. As metabolizable energy level increased from 2,500 to 2,900 kcal/kg of feed egg production, daily feed and protein intake and egg shell quality decreased, but reverse was true for the daily energy intake, energy requirement and feed cost per kg egg, body weight gain, nutrients utilizability and abdominal fat accumulation, Egg weight, viability and egg yolk Pigmentation were not affected by the dietary energy level. On the other hand, as dietary protein level increased from 13 to 17%, egg production, egg weight, daily protein intake, protein requirement per kg egg and body weight gain icreased, but daily feed and energy intake, feed and energy requirement per kg egg, egg yolk pigmentation and dry matter utilizability decreased, and no significant difference in the feed cost per kg egg, viability and egg shell quality was observed among dietary protein levels. However: the hens fed 15% and 17% Protein diets did not show significant differences in egg production, egg weight and body weight gain. For the entire laying period of 52 weeks, metabolizable energy level of 2,500 kcal/kg of feed and 15% dietary protein level were considered to be adequate to support the optimum productivity.

• Journal of Nutrition and Health
• /
• 제34권7호
• /
• pp.809-820
• /
• 2001

The purpose of the study was to find out the rich sources of vitamin B-complexes in Korea. Thirty kinds of vitamin B-complex (thiamin, riboflavin, and niacin) rich foods were selected based on vitamin content in 100g edible portion, single serving size, 100kcal energy content, and 1999 national annual food supply data. The results were summarized as follows: \circled1 Most of the thiamin rich foods selected were fishes: half of the foods selected was fishes when based on the contents in single serving size. On the other hand, about half of the foods selected were vegetables when based on the thiamin contents in 100kcal energy content. A relatively large number of food groups were included such as fishes, vegetables, beans, grains, meats, etc. when based on the contents in 100g edible portion, and national food supply data. \circled2 Most of the riboflavin rich foods selected were fishes and shellfishes, and vegetables: half of the foods selected were fishes and shellfishes when based on the content in 100g edible portion; two-thirds of the foods selected were vegetables when based on the content in single serving size; half of the foods selected were vegetables when based on the content in 100kcal. \circled3 The most important niacin sources are fishes: Most than 60% of the foods selected were fishes when based o the 100g edible portion, single serving size, and 100kcal energy content. Laver is very important source of all 3 vitamin B-complexes in Korea when based on the content in 100g edible portion, 100kcal energy content, and national annual food supply but not in single serving size. On the other hand, rice is rice is sources of all 3 vitamin B-complexes when based on the national annual food supply, but not in single serving size. On the other hand, rice sources of all 3 vitamin B-complexes when based on the national annual food supply, but is not included in 30 rich foods selected based on the content in 100g edible portion, single serving size, and 100kcal energy content. Mushrooms are also very important food sources of thiamin, riboflavin, and niacin when based on the vitamin content in 100g edible portion, single serving size, and 100kcal energy content but not included in 10 rich food selected based on the national food supply data.

• Korean Journal of Food Science and Technology
• /
• 제22권1호
• /
• pp.1-6
• /
• 1990

The thermal diffusivity of defatted and nondefatted starches were measured on the basis of one dimensional semi-infinitive theory. Differential scanning calorymetry was used to study the effects of cooling rate, fat and water contents on the enthalpy and entropy changes with the cooling rate of $-2.5{\sim}10^{\circ}C/min$. Thermal diffusivity of defatted and nondefatted straches were determined to be $4.14{\times}10^{-4}{\sim}4.96{\times}10^{-4}(m^2/h),\;4.09{\times}10^{-4}{\sim}4.81{\times}10^{-4}(m^2/h)$ in unfrozen state, and $2.78{\times}10^{-3}{\sim}3.91{\times}10^{-3}(m^2/h),\;2.26{\times}10^{-3}{\sim}3.57{\times}1-^{-3}(m^2/h)$ in frozen state respectively. On decreasing temperatures in frozen state, thermal diffusivities of starches were increased and entropy and enthalpy were decreased, and more rapid cooling rates resulted in a decrease in entropy. A linear relation was observed between enthropy, enthaly and water content. Thermal diffusivity was decreased, and entropy was increasing fat content. With water content ranging from 35 to 90%, enthalpy and entropy of straches were found to be $107{\sim}216 (kcal /moi),\;0.45{\sim}0.94(kcal/mol.\;K)$, respectively.

• Korean Journal of Food Science and Technology
• /
• 제34권6호
• /
• pp.1067-1072
• /
• 2002

Peroxidase was used as a standard enzyme to determine optimum blanching conditions of Flammulina velutipes and Lyophyllum ulmarium. Crude peroxidase extracted from raw mushrooms had maximum activity at $10{\sim}15^{\circ}C$ and pH 5.5 (50 mM, potassium phosphate buffer) using substrates of $H_2O_2$ and p-Phenylendiamine. Thermal inactivation of the crude peroxidase followed the first-order kinetics. The activation energy and z value of the crude peroxidase for F. velutipes were 59.58 kcal/mol and $9.0^{\circ}C$, whereas were 43.05 kcal/mol and $12.4^{\circ}C$ for L. ulmarium, respectively. On the basis of thermal kinetics parameters obtained, the optimum blanching conditions for F. velutipes and L. ulmarium were 1 min at $70^{\circ}C$ and 5 min at $80^{\circ}C$, respectively. Activation energies and z values of peroxidases extracted from heat-treated mushrooms were 7.97 and 6.55 kcal/mol, and $59.8^{\circ}C\;and\;74.1^{\circ}C$ for F. velutipes and L. ulmarium, respectively.

• ANNALS OF ANIMAL RESOURCE SCIENCES
• /
• 제28권2호
• /
• pp.56-63
• /
• 2017

This study was conducted to determine the effects of supplementary levels of dietary betaine and energy on nutrient digestibility and physiological responses in growing pigs exposed to heat stress. A total of 12 barrows ($L{\times}Y{\times}D$; initial BW, $67.1{\pm}0.98kg$) were allocated into individual metabolic crates. Experimental design was a $4{\times}4$ Latin square with dietary energy and betaine levels (3,300 and 3,400 kcal/kg; 0 and 0.5%, respectively) and the experimental period (n=4). Feeding trial was performed during summer season (July and August). Digestibility of crude fat was higher (p<0.01) in the ME 3,400 kcal/kg than the ME 3,300 kcal/kg, but did not differ by betaine (p>0.05). Blood corpuscles and biochemical components were not influenced by dietary energy and betaine levels (p>0.05). Serum IgG was greater (p<0.05) in the ME 3,400 kcal/kg than the ME 3,300 kcal/kg, but cortisol was not differ among the treatment groups (p>0.05). In conclusion, our results showed positive effects by energy levels rather than betaine. Thus, further study need investigation of effects of high energy level in the pigs exposed to heat stress.

• Journal of Animal Science and Technology
• /
• 제64권3호
• /
• pp.471-480
• /
• 2022

This experiment was conducted to determine the maximum dietary energy levels on growth performance and carcass characteristics of White Pekin duck. the Six dietary treatments were formulated based on their apparent metabolizable energy (AME) concentrations from 2,700 to 3,200 kcal/kg with a 100 kcal/kg gap to evaluate the accurate dietary AME requirement to address current knowledge and further issues for fulfilling the genetic potential of meat-type white Pekin ducklings. A total of 432 one-day-old male White Pekin ducklings were randomly allocated into one of six dietary treatments with six replicates (12 birds per pen). The diets were formulated as corn-soybean meal-based diets to meet or exceed the Nutrient Requirement of Poultry specification for meat-type ducks. Growth performance indices (i.e. average daily gain [ADG], average daily feed intake, feed conversion ratio) were measured weekly. Medium body weight (BW) ducklings from each pen were sacrificed to analyze the carcass traits and abdominal fat content on day 21. Obtained data were analyzed to estimate significant effect using the one-way ANOVA of IBM SPSS Statistics (Version, 25). If the p-value of the results were significant, differences in means among treatments were separated by Tukey's post hoc test. Significant differences were then analyzed with a linear and quadratic broken model to estimate the accurate concentration of AME. Ducklings fed higher dietary AME diets increased (p < 0.05) BW, ADG. Ducklings fed higher AME than 2,900 kcal/kg diets increased abdominal fat accumulation and leg meat portion. The estimated requirement by linear plateau method showed from 3,000.00 kcal/kg to 3,173.03 kcal/kg whereas the requirement by quadratic plateau method indicated from 3,100.00 kcal/kg to 3,306.26 kcal/kg. Collectively, estimated dietary requirements exhibit diverse results based on the measured traits and analysis methods. All the estimated requirements in this experiment present higher than previous research, the maximum requirement for the next diet formulation should be selected by the purpose of the diet.

• Applied Chemistry for Engineering
• /
• 제7권2호
• /
• pp.356-361
• /
• 1996

Cure kinetics of diglycidyl ether of bisphenol A(DGEBA)/4,4'-methylene dianiline(MDA) with hydroquinone-phenyl glycidyl ether(HQ-PGE) as a reactive additive, which was preliminarily synthesized, was investigated by DSC and FT-IR analyses. Kissinger equation and Arrhenius' equation were used to calculate activation energy and pre-exponential factor. When HQ-PGE was added to DGEBA/MDA system, it reduced activation energy of system. When the 5 phr of HQ-PGE was added to DGEBA/MDA system, activation energy was 7.8 kcal/mol by FT-IR analysis and 11.3 kcal/mol by DSC, in comparison with the system without HQ-PGE, activation energy decreased about 30% and 9%, respectively. According to these results, HQ-PGE, introducing agent of this system, acted as a catalyst.

• Korean Journal of Community Nutrition
• /
• 제6권3호
• /
• pp.371-379
• /
• 2001

The present study was conducted to determine whether the food shortage situation in North Korea has affected its people differentially according to social class. We performed a literature search on North Korean books and documents on food and nutrition. We also conducted a mail survey on North Korean defectors to estimate the energy and nutrient intake and the practice of foraging for wild foods at the time of food crisis in North Korea. The subjects were 150 adults, 104 men and 46 women, aged 20 years and older, who resettled in the South Korea after the food crisis. The mean energy intakes for men and women were estimated to be 1,260 kcal and 980.6 kcal, respectively, which were far less than 2,900 kcal and 2,600 kcal, the intake levels recommended for North Korean men and women, respectively. Thirty seven percent of the subjects reported a lack of foods adequate enough for work and other daily activities, and fifty seven percent reported a routine use of wild foods such as roots, grass, stalks, and tree bark with an average of 4 items per day. Food consumption patterns on a typical day were different by social classes with the high class people consuming an affluent diet in the midst of a severe food shortage.

• Korean Journal of Community Nutrition
• /
• 제6권3호
• /
• pp.486-494
• /
• 2001

This study was performed to assess the nutrient intakes and diet quality of rural middle school students provided with and without the national school lunch program(NSLP). The data on dietary intakes were obtained by using food record method questionnaires which were collected from 340 rural middle school students provided with(n=177) and without (n=163) NSLP. Diet quality was accessed by NAR(nutrient adequacy ration), MAR(mean adequacy ration), and INQ( index of nutritional quality). Total energy intakes of the boys were 2123 kcal with NSLP and 1857 kcal without NSLP. Total energy intakes of the girls were 1913 kcal with NSLP and 1814 kcal without NSLP. Phosphorus, vitamin A, vitamin E, ascorbic acid, thiamin, riboflavin, and niacin intakes were above the RDA in the NSLP group. For those without NLSP, phosphorus, vitamin E, thiamin intakes were above RDA, however, calcium, iron vitamin A, vitamin $B_6$ were less than the RDA. The mean adequacy ration(MAR), an index of dietary quality was 0.69(with) 0.62(without) for males and 0.62(without) for females The indexes of nutritional quality(INQ) were over 1 for most nutrients except calcium, vitamin A, vitamin B$_2$ and zinc. The study showed that total daily energy and nutrient intakes were significantly higher in students provided with than those without school-lunches. Thus, the school-lunch program is recommenced and necessary to improve the nutritional status of middle school students.

• Korean Journal of Community Nutrition
• /
• 제8권3호
• /
• pp.270-279
• /
• 2003

Middle and high school students in Korea spend a lot of time at school. In other words, many Korean teenagers spend most of their time studying, and have little time for other activities, such as physical workouts. Fewer physical activities, and consumption of many snacks, etc. may lead to overweight or obesity in some teenagers. This study was conducted to find out the activity levels of teenagers' in order to calculate their daily energy expenditures. A total of 1,192 students (461 middle school students and 731 high school students) who lives in either a city or a country area were recruited for this study. One-day Activity Diaries were collected using questionnaires and analyzed by means of SPSS /win. The participating students spent about 7 hours 24 minutes resting including sleeping; 6 hours 28 minutes studying ,4 hours 4 minutes in leisure activities , 1 hour 32 minutes in personal hygiene activities such as washing, dressing and undressing, etc., 50 minutes on transportation : and 23 minutes on household chores such as cleaning, doing the laundry, etc. The average activity factor was 1.49. That of middle school female students was the lowest at 1.47, followed by middle school male students at 1.48, high school female students at 1.49, and high school male students at 1.51. The daily energy expenditure of middle and high school male students was 2,289 kcal and 2,600 kcal, respectively. That of female students was 1,959 kcal and 2,067 kcal, respectively.