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Studieson Titanium Enamel Frit (티타늄琺瑯후릿트에 關한 硏究)

  • Lee, Chong-Keun;Han, Ki-Sung
    • Journal of the Korean Chemical Society
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    • v.4 no.1
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    • pp.18-26
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    • 1957
  • There are two problems to be solved by our efforts in the enamel frit. One is how we can cover the enamel frit thin with complete milk white as possible, and the other is how it can be, made resistant for chemicals than before one. The frit which can solved the two problems just mentioned above is titanium enamel frit. This frit has been developed in America after War Ⅱ, and now the research for concerning antimony frit into titanium frit is under development entirely. In order to develope the enamel industry in Korea, it is urgent problem to convert antimony frit into titanium frit. By the way the titanium frit is emulsified titanium oxide crystal which made through reheating the supersaturated solution of titanium oxide in the basis of glass. Unfortunately, there are many obscure points in active fact or which influence on its composition and characteristics yet. However, this task was tried for the first in Korea. As first step, the test was carried on the reference books, and we can be possible convert antimony frit into titanium frit as a result of this experiment. As a conclusion, for the purpose of developing the enamel industry in Korea, we studied that the research for converting antimony enamel frit which has been used popularly into titanium enamel frit which is more economic and resistant for chemicals. As a result of experiments, the following points concerning with titanium frit have become clearly. 1. It is better when the composition of titanium enamel frit has as following table.Man Duck San Silica 24 An Yang Feldspar 20 Borax 28 Sodium Nitrate 4 Cryolite 7 Calcium Carbonate 3.6∼1 Titanium Oxide 10 Calcium phosphate 0 ∼3.2 Calcium Fluoride 0∼1.8 Antimony Oxide 0∼0.5 2. The amount of $TiO_2$, to be added is $10%\;to\;12{%,\;CaF_2\;is\;under\;1.8%,\;P_2O_5\;is\;under\;1.6%,\;Sb_2O_3\;is\;under\;0.5%$. 3. In the titanium frit, the limit of iron oxide amount to be included is under 0. 5%. 4. Comparing the titanium enamel frit with antimony enamel frit not only the titanium frit can be savely 20.6% in the price of raw materials, but one time of glazing and heating process is omitted in each case, and it is known the titanium frit is more resistant for chemicals than antimony frit.

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Effects of dietary energy and lysine levels on physiological responses, reproductive performance, blood profiles, and milk composition in primiparous sows

  • Hong, Jinsu;Fang, Lin Hu;Kim, Yoo Yong
    • Journal of Animal Science and Technology
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    • v.62 no.3
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    • pp.334-347
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    • 2020
  • The adequate intake of energy and lysine for primiparous sows are necessary for maternal growth of sows and growth of their progeny. This study was conducted to evaluate the effects of dietary energy and lysine levels on primiparous sows and their progeny. A total of 48 gilts (Yorkshire × Landrace), with an initial body weight (BW) of 168.1 ± 9.71 kg and at day 35 of gestation, were allotted to eight treatment groups with a 2 × 4 factorial arrangement. The first factor was metabolizable energy levels in diet (3,265 or 3,365 kcal of ME/kg), and the second factor was lysine levels in diet (gestation 0.55%, 0.65%, 0.75%, 0.85%, lactation 0.70%, 0.85%, 1.00%, 1.15%). The BW gain (p = 0.07) and backfat thickness (p = 0.09) in the gestation period showed a tendency to be increased in sows fed the high-energy diets. In the lactation period, sows fed the high-energy diets tended to be greater BW (p = 0.09) and less BW loss (p = 0.05) than those of sows fed the low-energy diets. Sows fed high-energy diets had a tendency of greater piglet weight at day 21 of lactation and greater piglet weight gain (p = 0.08 and p = 0.08, respectively). Although the blood urea nitrogen (BUN) was increased linearly as dietary lysine level increased at day 110 of gestation (Linear, p = 0.03), the BUN was decreased linearly as dietary lysine level increase at day 21 of lactation (Linear, p < 0.01). In the composition of colostrum, sows fed high-energy diets had greater casein, protein, total solid, solid not fat, and free fatty acid concentrations than those of sows fed low-energy diets (p < 0.05). Supplementation of total lysine 0.75% for gestation and 1.00% for lactation with 3,365 kcal of ME/kg energy level could be applied to the primiparous sows' diet to improve performance of sows and growth of their progeny.

Effects of a multi-strain probiotic on growth, health, and fecal bacterial flora of neonatal dairy calves

  • Guo, Yongqing;Li, Zheng;Deng, Ming;Li, Yaokun;Liu, Guangbin;Liu, Dewu;Liu, Qihong;Liu, Qingshen;Sun, Baoli
    • Animal Bioscience
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    • v.35 no.2
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    • pp.204-216
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    • 2022
  • Objective: The aim of this study was to investigate the effects of dietary supplementation with a multi-strain probiotic (MSP) product containing of Bifidobacterium animalis, Lactobacillus casei, Streptococcus faecalis, and Bacillus cerevisiae on growth, health, and fecal bacterial composition of dairy calves during the first month of life. Methods: Forty Holstein calves (24 female and 16 male) at 2 d of age were grouped by sex and date of birth then randomly assigned to 1 of 4 treatments: milk replacer supplementation with 0 g (0MSP), 2 g (2MSP), 4 g (4MSP), and 6 g (6MSP) MSP per calf per day. Results: Supplementation of MSP did not result in any significant differences in parameters of body measurements of calves during the 30 d period. As the dosage of MSP increased, the average daily gain (p = 0.025) and total dry matter intake (p = 0.020) of calves showed a linear increase. The fecal consistency index of the 2MSP, 4MSP, and 6MSP group calves were lower than that of the 0MSP group calves (p = 0.003). As the dosage of MSP increased, the concentrations of lactate dehydrogenase (p = 0.068) and aspartate aminotransferase (p = 0.081) in serum tended to decrease, whereas the concentration of total cholesterol increased quadratically (p = 0.021). The relative abundance of Dorea in feces was lower (p = 0.011) in the 2MSP, 4MSP, and 6MSP group calves than that in the 0MSP group calves. The relative abundance of Dorea (p = 0.001), Faecalibacterium (p = 0.050), and Mitsuokella (p = 0.030) decreased linearly, whereas the relative abundance of Prevotella tended to increase linearly as the dosage of MSP increased (p = 0.058). Conclusion: The MSP product can be used to reduce the diarrhea, improve the performance, and alter the composition of the fecal bacteria in neonatal dairy calves under the commercial conditions.

Mass Cultivation of Rhodococcus sp. 3-2, a Carbendazim-Degrading Microorganism, and Development of Microbial Agents (카벤다짐 분해 미생물인 Rhodococcus sp. 3-2의 대량 배양 및 미생물 제제 개발)

  • Jun-Kyung Park;Seonghun Im;Jeong Won Kim;Jung-Hwan Ji;Kong-Min Kim;Haeseong Park;Yeong-Seok Yoon;Hang-Yeon Weon;Gui Hwan Han
    • Korean Journal of Environmental Agriculture
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    • v.42 no.4
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    • pp.259-268
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    • 2023
  • Rhodococcus sp. 3-2 strain has been reported to degrade benzimidazole-based pesticides, such as benomyl and carbendazim. Therefore, this study aimed to optimize culture medium composition and culture conditions to achieve cost-effective and efficient large-scale production of the Rhodococcus sp. 3-2 strain. The study identified that the optimal media composition for mass culture comprised 0.5% glucose, 0.5% yeast extract, 0.15% NaCl, 0.5% K2HPO4, 0.5% sodium succinate, and 0.1% MgSO4. Additionally, a microbial agent was developed using a 1.5-ton fermenter, with skim milk (20%), monosodium glutamate (15%), and vitamin C (2%) as key components. The storage stability of the microbial agent has been confirmed, with advantages of low temperature conservation, which helps to sustain efficacy for at least six months. We also assessed the benomyl degradation activity of the microbial agent within field soil. The results revealed an over 90% degradation rate when the concentration of viable cells exceeded 2.65 × 106 CFU/g after a minimum of five weeks had elapsed. Based on these findings, Rhodococcus sp. 3-2 strain can be considered a cost-effective microbial agent with diverse agricultural applications.

A Comparative Study of Dry Matter Yield and Nutritive Value of Autumn Sown Forage Crops in Daejeon Area (대전지역 추파 사료작물의 건물수량 및 사료가치 비교 연구)

  • Lee, Hyung-Suk;Lee, In-Duk
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.26 no.4
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    • pp.249-256
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    • 2006
  • The object of this experiment was to suggest the optimum autumn sown small forage crops as next forage crops harvested maize in Daejeon area. The field trials was conducted from 2002 to 2004 at Chungnam National University in order to evaluate the dry matter yield and qualities of the autumn sown small forage crops. The experiment was consisted of split plots (main plot : forage crops as rye, barley and wheat, and sub plot 4 harvest stages as boot, heading, milk and dough) design with three replications. The average DM yield for 2 years of rye was higher than that of other forage crops (p<0.01). As stages proceed, the DM yield tended to increase in all forage crops (p<0.01). In chemical composition, they had a difference on forage crops and stages. The crude protein (CP) was higher in barley (p<0.01), but fibrous contents such as NDF, ADF, cellulose and lignin were lower in wheat than in the other forage crops (p<0.01). In Daejeon area, although barley and wheat at milk and dough stages were observed with maximum yield and high quality as autumn sown forage crops, due to late harvesting periods, it is difficult to utilize them as previous forage crops seeded in maize. Based on the result mentioned above, it is concluded that rye harvested at boot to heading stages is the most suitable fur autumn sown small forage crops in Daejeon area. Meanwhile, in order to have the option of nutritional value in wheat and barley, they need to be supplied early maturing and high-yield variety of wheat and barley.

Menu pattern and food diversity of snack menus provided by Child Care Information Centers in Seoul (서울시 소재 육아종합지원센터에서 제공하는 어린이집 간식식단의 유형 및 식품 다양성)

  • Yeoh, Yoonjae;Kwon, Sooyoun;Lee, Youngmi
    • Journal of Nutrition and Health
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    • v.47 no.6
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    • pp.443-451
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    • 2014
  • Purpose: This study was conducted for analysis of menu pattern and food diversity of snack menus of child care centers in order to provide preliminary data for establishment of related guidelines for snack menus for child care centers. Methods: Data from 630 snack menus (350 for morning snacks and 280 for afternoon snacks) of March, 2013 from 14 Child Care Information Centers in Seoul provided for child care centers were analyzed. In addition, the menu pattern and food diversity of morning snack menus were compared with those of afternoon snack menus. Results: Differences in menu pattern and food diversity were observed between morning and afternoon snack menus. The majority of snack menus (66.8%) included two menu items and the numbers of menu items of afternoon snack menus were significantly larger than those of morning snack menus. The percentages of "Grains (G)" and "Grains (G) + Milk (D)" patterns were higher in snack menu (G: 18.9%, G+D: 17.1%). Approximately one third of snack menus were composed of only one food group. In addition, 45.6 % of all snack menus comprised milk and only 23.0% included fruits. Conclusion: These results demonstrated the need for improvement in food composition and diversity of snack menus provided by Child Care Information Centers for child care centers. Therefore, to ensure children's intake of nutritionally balanced snacks, it will be necessary to establish more detailed guidelines for the menu pattern and food composition in snack menus for child care centers.

Potentials of Synbiotics for Pediatric Nutrition and Baby Food Applications: A Review (소아 영양 및 유아식 응용을 위한 신바이오틱스의 잠재력: 총설)

  • Jung, Hoo Kil;Kim, Sun Jin;Seok, Min Jeong;Cha, Hyun Ah;Yoon, Seul Ki;Lee, Nah Hyun;Kang, Kyung Jin
    • Journal of Dairy Science and Biotechnology
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    • v.33 no.2
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    • pp.111-118
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    • 2015
  • Probiotic, prebiotic, and synbiotic substances as well as microorganisms were added to infant formula in an attempt to influence the intestinal microflora with an aim to stimulate the growth of lactic acid bacteria, especially bifidobacteria and lactobacilli. Over the last 10 years, new synbiotic infant formulas containing probiotics and prebiotics have been proposed in order to simulate the effect of breast-feeding on the intestinal microflora. Owing to their synergistic effect, the new synbiotics are expected to be more helpful than using probiotics and prebiotics individually. Maintenance of the viability of the probiotics during food processing and the passage through the gastrointestinal tract should be the most important consideration, since a sufficient number of bacteria ($10^8cfu/g$) should reach the intended location to have a positive effect on the host. Storage conditions and the processing technology used for the manufacture of products such as infant formula adversely affect the viability of the probiotics. When an appropriate and cost-effective microencapsulation methodology using the generally recognized as safe (GRAS) status and substances with high biological value are developed, the quality of infant formulas would improve. The effect of probiotics may be called a double-effect, where one is an immunomodulatory effect, induced by live probiotics that advantageously alter the gastrointestinal microflora, and the other comprises anti-inflammatory responses elicited by dead cells. At present, a new terminology is required to define the dead microorganisms or crude microbial fractions that positively affect health. The term "paraprobiotics" (or ghost probiotics) has been proposed to define dead microbial cells (not damaged or broken) or crude cell extracts (i.e., cell extracts with complex chemical composition) that are beneficial to humans and animals when a sufficient amount is orally or topically administered. The fecal microflora of bottle-fed infants is altered when the milk-based infant formula is supplemented with probiotics or prebiotics. Thus, by increasing the proportion of beneficial bacteria such as bifidobacteria and lactobacilli, prebiotics modify the fecal microbial composition and accordingly regulate the activity of the immune system. Therefore, considerable attention has been focused on the improvement of infant formula quality such that its beneficial effects are comparable to those of human milk, using prebiotics such as inulin and oligosaccharides and potential specific probiotics such as bifidobacteria, which selectively stimulate the proliferation of beneficial bacteria in the microflora and the indigenous intestinal metabolic activity of the microflora.

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Current Status and Prospects of Community Nutrition in Korea (한국 지역사회영양의 현황과 전망)

  • 채범석;한정호
    • Korean Journal of Community Nutrition
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    • v.1 no.1
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    • pp.9-27
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    • 1996
  • The nutritional status is strictly related with flood production, flood processing, and distribution along with habits, education and technological achievement, adapted and adjusted to socio-economic conditions. All these factors are independently affecting the nutritional status of populations. In addition to the above mentioned factors launch of it is useful to consider two points ; unification of the South and the North Korea and WTO. The present study gives and overview of basic knowledge about nutritional status of Korean by using availab1e data in relation to nutrition. The basic characteristics of Korean diet with proportions high in carbohydrate and low in fat, have been relatively constant for the past two decades. The average daily flood intake in terms of weight of flood per person is relatively constant throughout the years. Although the proportion of animal food intake tends to increase recently, the Korean diet is still insufficient in meat, eggs, milk, and fish. Moreover because milk has not been accustomed flood with the general population and not much used in traditional flood preparation in Korea, milk consumption was especially low in comparison with western countries. The total energy intake was relatively constant throughout the years from 1969 to 1993. However, changes in the composition have occurred in the past two decades. The amount and proportions of fat have been s1ightly increasing while the total amount of carbohydrate has been decreasing. The nutrition preblems of Korea have changed over the past severa1 decades. The general adequacy of protein and energy existing after Korean War(1950) was resolved now. Since then the average diet appears to be nearly desirable in terms of rapid rates of growth during childhood and attainment of progressively stature and body weight at maturity. The dietary habits of some young people in these days seem to be taking a more western style diets. This trends if established by habit may lead to a marked change in the traditional diet and health. I think Korean nutritional experiences have potential values for tole other countries in Asia and in western countries. Korean diet illustrates a high level of nutritional status and health attainable will a largely vegetable diet : high in complex carbohydrates, and dietary fibre, and low in tat, and reasonable amount of total protein. This is significant for developing and developed countries that must select specific goals fir adequate nutrition for the people. Compared to the western countries, Koreas different incidence of coronary heart disease and malignancy demonstrates the significance of environment and probably the prominent role of diet in the development of these diseases. The changes occurring in the Korean diet of fir the unusual opportunity to assess the effect of diet upon chronic degenerative disease. In the future, the Korean diet might be continue to change significantly These changes are being influenced by socioeconomic factors that have been emerging and growing stronger since mid-l980 and that probably continue to be potent. The expanded purchasing power of the consumer results in increased discretionary purchases. In the case of foodstuffs, the consumer demands appear to be directed toward items of higher protein content, which, being primarily animal products, are inevitably accompanied by an increased consumption of fat. The continued availability of these more expensive flood items depends upon the balance of foreign trade favouring their importation and domestic production. A regression of foreign trade could result in a decreased supply for the consumer, whereas continued growth of trade iou]d provide freedom for increasing availability to the consumer. In this latter situation the exact choice of foodstuffs is depending upon comsumer tastes and the pressures that may influence it.

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Effect of the Cooking Condition on Enzyme-resistant Starch Content and in vitro Starch and Protein Digestibility of Tarakjuk (Milk-rice Porridge) (타락죽의 효소저항전분 함량과 in vitro 전분 및 단백질 분해율에 대한 가열조건의 영향)

  • Lee, Gui-Chu;Lim, Seung-Taik;Yoon, Hyun-Sung
    • Korean Journal of Food Science and Technology
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    • v.36 no.5
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    • pp.765-772
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    • 2004
  • Cooking condition of Tarakjuk (milk-rice porridge) was established based on gelatinization temperature using differential scanning calorimetry (DSC) of roasted Ilpum rice flour, which has highest enzyme-resistant starch (RS) content. Effect of cooking temperature and time on DSC characteristics, crystallity with X ray diffractogram, RS content, in vitro starch digestibility (IVSD), amino acid composition, and in vitro protein digestibility (IVPD) of Tarakjuk were determined. Tarakjuk was cooked at 50, 56.5, 64, and $69^{\circ}C$ for various durations. Rice flour ingredient used was Ilpum, previously roasted at $185^{\circ}C$ for 25 min. Tarakjuk cooked at 50 and $56.5^{\circ}C$ showed two thermal transitions between $63.7-125.2^{\circ}C$ as determined by DSC, corresponding to endotherms of starch gelatinization $(63.7-73.8^{\circ}C)$ and melting of amylose-lipid complex (AM-lipid complex, $97.7-125.2^{\circ}C$), whereas that cooked at 64 and $69^{\circ}C$ showed only AM-lipid complex melting transition between $96.9-127.6^{\circ}C$. As cooking temperature increased, RS content of Tarakjuk decreased, whereas IVSD increased. Total amino acid content was between 11,558-15,601mg/100g, depending on cooking condition used. Compared with conventionally made control, contents of essential amino acids, such as lysine and tryptophane, were higher at 50 and $56.5^{\circ}C$, and IVPD showed higher increase. Results reveal degree of gelatinization in Tarakjuk with high RS content as well as low IVSD and high IVPD, which are important from physiological and nutritional point of view, can be produced by controlling cooking condition.

A Study on the Economical Nutrition Supplement of Cereal Food for Improvement in our National Eating Habits (국민식생활(國民食生活) 향상(向上)을 위(爲)한 곡류제품(穀類製品)의 경제적( 經濟的) 영향강화(營養强化)에 관(關)한 연구(硏究))

  • Ju, Jin-Soon;Yu, Jong-Yull;Kim, Sook-He;Lee, Ki-Yull;Han, In-Kyu
    • Journal of Nutrition and Health
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    • v.6 no.1
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    • pp.1-9
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    • 1973
  • I. Subject of the Study: Studies on the economical nutrition supplement of cereal foods for the improvement in our notional eating habits. II. Purpose and Importance of the Study: 1. Our nation is confronted with the situation that the rice, a principal food, short of some essential amino acids, lysine and threonine, leads to imbalanced meals insufficient in the nutrient of protein, to bring many difficulties in the elevation of our national physique. 2. The shortage of even the rice imperfect in the nutrient of protein makes the import of lots of foreign rice inevitable. It is considered that the protein supplement and decrease in the consumption amount, of rice, is a serious key to the solution of our food difficulty, and then a way of the proetin supplement of rice through the addition of essential amino acid is to be rarely applied in the view of the our present finance and situation. 3. In the present experiment, therefore, it aims to the suggestion of an aspect of the improvement in our national eating habits guiding in the nutrition elevation which our nation can afford economically through the development of first, a way of the protein supplement by the mixture of cereals producted plentifully in our country, and second, a way of the decrease in the consumption amount and the improvement in the nutrition of rice through the substitution of the other cereals for rice. III. Contents of Scope of the Study: 1. Objects of the study: Objects of the study are the following three items; a) The nutrition supplement of rice through the mixture of cereals. Our nation makes mainly rice as a principal food, but practically many kinds of cereal are produced in our country. They contain different levels and qualities of each nutrient and they are different from one another in the kinds of essential amino acid consisting protein. For that reason, the mutual complement efficeincy of insufficient nutrients is observed through the mixture of cereals. b) The nutrition supplement of rice through the addition of superior protein sources to rice, a principal food. The development of rice as superior foods in the sense of nutrition is conducted through the risement in protein quality by the addition of protein sources in good quality, for example, fish flour (anchovy flour), egg powder, milk powder, and so on, and through the supplement of vitamins and minerals. c) The decrease in the consumption amount of rice through the substitution of the other cereals for rice, as a principal food. The compensation for the short amount of rice is made by the reduction in the consumption of rice through the discovery of a way of substitution of the other cereals for rice, as a principal food and of the settlement of problems in nutrition and finance subsequent to this. 2. Contents of the study: a) An ideal mixture-ratio of cereals is established for rats by feeding mixed foods(rice-barely or rice-wheat) containing 5%, 15%, 25%, 35% and 45% level of either barely or wheat. b) The nutritive value is determined in the whole subsititution of other foods for rice, and then, a way of the complement of over and under nutrients is devised. c) The ideal combination is investigated for rats through feeding mixed foods of main food, rice and supplement foods of protein sources, soy bean, fish flour, egg powder and milk Powder. d) According to results from the above three experiments, the concise functional test for men and the examination of economical property are made. 3. Scope of the study: a) The observation of the effect of each diet on the growth rate for rats. The growth rate of rats was observed for 15 groups of mixed foods of a main food, rice, and wheat flour, barley powder or soy bean powder, respectively, and 12 groups of wheat flour diets supplemented with $1{\sim}3%$ milk powder, and rice or wheat flour diets supplemented with 5% of milk powder, egg powder, fish flour or soy bean powder, respectively. b) The determination of food consumption. The food consumption was determined at weekly intervals for 27 kinds of diet described in a) item. c) The determination of food efficiency rate. The food efficiency rate for each diet was determined by calculation from the gained body weight and the food consumption amount at the same intervals described in b) item. d) The determination of protein efficiency rate. The protein efficiency rate for each diet was determined by calculation form gained body weight and the protein amount of the food consumption amount at the same intervals described c) item. e) The determination of the body component. The hematocrite and hemoglobin levels in the blood, total nitrogen in the serum, blood sugar, and lipids and glycogen in the liver were determined. f) The observation of nitrogen balance. As a means of the observation of nitrogen balance, the total nitrogen in the urine was determined. g) The analysis of economical property. The economical property was analyzed as the gained body weight to the amount equivalent to one won through the conversion of the food consumption amount into money. h) The functional test for men. The concise functional test for men was made in order to establish if the best diet for experimental animals can be applied to men. IV. Results of the Study: The national food product plan, nationwide nutritive enlightment and the improvement activities in our country eating habits, especially, mixed and powder food problems are to be significantly referred, and the following results must be applied. a) In the mixed foods of cereals, the mixed food of the rice-barley containing $5{\sim}15%$ level of barley is best in terms of nutrition. b) The addition of superior protein sources, egg, Bilk, soy bean, or fish, respectively to either rice or wheat flour makes a great risement in the nutritive value. c) The animal protein is more effective in the elevation of nutritive value of cereals. d) Rice takes the most nutritive operation and has the highest preference, among rice, wheat flour and barley. e) Wheat flour is more economical than rice in evaluation of the gained body weight to the regular money, and the addition of fish or soy bean is more economical than that of any other supplement food. But the above results are true of the range of nutrition and economical property. f) The study on the nutrition composition and barley will lead to the improvement in our national eating habits as mixed food of the rice-barley containing $5{\sim}15%$ level of barley is more nutritive. g) This study on the nutrition only for the growing animal can not be considered as a perfect and entire evaluation. Consequently, the perfect data for our national nutrition can be obtained from the experiment similar to this for the much longer period examining, in details, the growth rate, change of physical strength, mental and bodily change, average life span, and resistance ability to infectious diseases.

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