• Title/Summary/Keyword: Nutritive Value

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Rumen fermentation, methane production, and microbial composition following in vitro evaluation of red ginseng byproduct as a protein source

  • Hamid, Muhammad Mahboob Ali;Moon, Joonbeom;Yoo, Daekyum;Kim, Hanbeen;Lee, Yoo Kyung;Song, Jaeyong;Seo, Jakyeom
    • Journal of Animal Science and Technology
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    • v.62 no.6
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    • pp.801-811
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    • 2020
  • The main objective of this in vitro study was to evaluate red ginseng byproduct (RGP) as a protein resource and its effects on rumen fermentation characteristics, microflora, CO2, and CH4 production in ruminants. Four treatments for in vitro fermentation using buffered rumen fluid over a 48 h incubation period were used: 1, RGP; 2, corn gluten feed (CGF); 3, wheat gluten (WG); and 4, corn germ meal. In vitro dry matter digestibility (IVDMD), in vitro neutral detergent fiber digestibility (IVNDFD), in vitro crude protein digestibility (IVCPD), volatile fatty acids, pH, and ammonia nitrogen (NH3-N) were estimated after 48 h incubation. Gas production was investigated after 3, 6, 12, 24, 36 and 48 h. The CO2 and CH4 were evaluated after 12, 24, 36, and 48 h. A significant difference in total gas production and CO2 emissions was observed (p < 0.01) at all incubation times. CH4 production in RGP were higher (p < 0.05) than that in other treatments but a higher CH4 portion in the total gas production was observed in WG (p < 0.05) at 48 h incubation. The IVDMD, IVNDFD, and IVCPD of RGP was lower than those of other conventional ingredients (p < 0.01). The RGP had the lowest NH3-N value among the treatments (p < 0.01). The RGP also had the lowest total VFA concentration (p < 0.01), but presented the highest acetate proportion and acetate to propionate ratio among the treatments (both, p < 0.01). The abundance of Prevotella ruminicola was higher in RGP than in WG (p < 0.01), whereas RGP has lower methanogenic archaea (p < 0.01). In conclusion, based on the nutritive value, IVDMD, low NH3-N, and decreased methanogenic archaea, RGP inclusion as a protein source in ruminant diets can be an option in replacing conventional feed sources.

THE USE OF NEAR INFRARED REFLECTANCE SPECTROSCOPY(NIRS) TO PREDICT CHEMICAL COMPOSITION ON MAIZE SILAGE

  • D.Cozzolino;Fassio, A.;Mieres, J.;Y.Acosta
    • Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
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    • 2001.06a
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    • pp.1610-1610
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    • 2001
  • Microbiological examination of silage is of little value in gauging the outcome of silage, and so chemical analysis is more reliable and meaningful indicator of quality. On the other hand chemical assessments of the principal fermentation products provide an unequivocal basis on which to judge quality. Livestock require energy, protein, minerals and vitamins from their food. While fresh forages provide these essential items, conserved forages on the other hand may be deficient in one or more of them. The aim of the conservation process is to preserve as many of the original nutrients as possible, particularly energy and protein components (Woolford, 1984). Silage fermentation is important to preservation of forage with respect of feeding value and animal performance. Chemical and bacteriological changes in the silo during the fermentation process can affect adversely nutrient yield and quality (Moe and Carr, 1984). Many of the important chemical components of silage must be assayed in fresh or by extraction of the fresh material, since drying either by heat or lyophilisation, volatilises components such as acids or nitrogenous components, or effects conversion to other compounds (Abrams et al., 1987). Maize silage dorms the basis of winter rations for the vast majority of dairy and beef cattle production in Uruguay. Since nutrient intake, particularly energy, from forages is influenced by both voluntary dry matter intake and digestibility; there is a need for a rapid technique for predicting these parameters in farm advisory systems. Near Infrared Reflectance Spectroscopy (NIRS) is increasingly used as a rapid, accurate method of evaluating chemical constituents in cereals and dried forages. For many years NIRS was applied to assess chemical composition in dry materials (Norris et al., 1976, Flinn et al., 1992; Murray, 1993, De Boever et al., 1996, De la Roza et al., 1998). The objectives of this study were (1) to determine the potential of NIRS to assess the chemical composition of dried maize samples and (2) to attempt calibrations on undried samples either for farm advisory systems or for animal nutrition research purposes in Uruguay. NIRS were used to assess the chemical composition of whole - plant maize silage samples (Zea mays, L). A representative population of samples (n = 350) covering a wide distribution in chemical characteristics were used. Samples were scanned at 2 nm intervals over the wavelength range 400-2500 nm in a NIRS 6500 (NIRSystems, Silver Spring, MD, USA) in reflectance mode. Cross validation was used to avoid overfitting of the equations. The optimum calibrations were selected on the basis of minimizing the standard error of cross validation (SECV). The calibration statistics were R$^2$ 0. 86 (SECV: 11.4), 0.90 (SECV: 5.7), 0.90 (SECV: 16.9) for dry matter (DM), crude protein (CP), acid detergent fiber (ADF) in g kg$\^$-1/ on dry matter, respectively for maize silage samples. This work demonstrates the potential of NIRS to analyse whole - maize silage in a wide range of chemical characteristics for both advisory farm and nutritive evaluation.

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Studies on the Nutritional Effects of Locally Produced Dried Formula Milk and Fermented Milk -1. Comparative Studies on the Nutrients Content of Dried Formula Milk and Fermented Milk- (국산(國産) 조제분유(調製粉乳)와 발효유(醱酵乳)의 영양효과(營養效果)에 관(關)한 연구(硏究) - 1. 유제품(乳製品)의 영양소(營養素) 함량비교(含量比較)를 위한 연구(硏究) -)

  • Paik, Jeong-J.;Han, In-K.
    • Journal of Nutrition and Health
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    • v.9 no.1
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    • pp.84-91
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    • 1976
  • Chemical determination were made to analyze the concentration of nutrients including proximate composition, vitamins, minerals, amino acids and fatty acids in three kinds of locally produced infantile formula milk(DFM) and one fermented milk(FM). An attempt was also made to compare the analytical values of nutrients against guaranteed values. The results obtained are summarized as follows; 1. The analyzed value of protein and fat content in DFM-A.B.C was slightly lower than that of guaranteed values and a reverse trend was observed in the case of total carbohydrate. There were no differences in proximate composition among the three kinds of DFM. It was found that the FM contained less protein and fat than the fresh milk, but it seemed that a considerable amount of sugar was added to FM. 2. The analyzed values of vitamin $A(2{\sim}3\;times)$ and $E(4{\sim}6\;times)$ contents in DFMS were higher than those of the guaranteed values except niacin. There were a little differences in vitamin contents among DFMS analyzed. 3. In the case of minerals, the analyzed values were similar to the guaranteed values except the calcium concentration that analyzed value was much higher than guaranted value. When the DFMS were diluted to 15% by adding water to compare with the human and fresh cow milk, it was found that the diluted DFMS resembled the human milk rather than cow milk in the content of energy, carbohydrates, protein and ash. The higher contents of iron and most vitamins in the diluted DFMS than the human milk or cow milk would indicate that they were fortificated with these nutrients. When these diluted DFMS were compared with the Korean R.D.A. for infant, it was clear that they could supply sufficient amount of the nutrients required by R.D.A. except the niacin which failed to reach the recommended level. The fact that iron content of DFM-C was not sufficient while vitamin A supply was excessive by 6 fold would indicate that further studies for the improvement may be necessary. 4. There was a little difference among DFMS in amino acid composition. The similarity of the essential amino acids composition between DFMS and cow milk indicated that there was no modification of the essential amino acids. However, present data showed that the amino acid compositon of FM was similar to that of the cow milk. 5. There was no difference among DFMS in the degree of saturation of fatty acids. The similar or higher levels of essential fatty acids contents of DFMS as compared with human milk revealed that essential fatty acids were added to DFMS during the course of process. From the experimental results described above, it may be concluded that the nutritive effects of three kinds of locally produced DFMS were much alike. It was also found that macro and micro nutrient composition except amino acid composition of locally produced dried formula milk was very much similar to that of the human milk. Moreover, fortification of iron and vitamins resulted in improving their nutritive values as the single form of infantile food, but it seemed that more consideration should be given on the fortification of some nutrients.

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A Study on the Nutritive Value and Utilization of Powdered Seaweeds (해조의 식용분말화에 관한 연구)

  • Yu, Jong-Yull;Lee, Ki-Yull;Kim, Sook-Hee
    • Journal of Nutrition and Health
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    • v.8 no.1
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    • pp.15-37
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    • 1975
  • I. Subject of the study A study on the nutritive value and utilization of powdered seaweeds. II. Purpose and Importance of the study A. In Korea the shortage of food will be inevitable by the rapidly growing population. It will be very important study to develop a new food from the seaweeds which were not used hitherto for human consumption. B. The several kinds of seaweeds have been used by man in Korea mainly as side-dishes. However, a properly powdered seaweed will enable itself to be a good supplement or mixture to certain cereal flours. C. By adding the powdered seaweed to any cereals which have long been staple foods in this country the two fold benefits; saving of cereals and change of dietary pattern, will be secured. III. Objects and scope of the study A. Objects of the study The objects will come under four items. 1. To develop a powdered seaweed as a new food from the seaweeds which have been not used for human consumption. 2. To evaluate the nutritional quality of the products the analysis for chemical composition and animal feeding experiment will be conducted. 3. Experimental cocking and accepability test will be conducted for the powdered products to evaluate the value as food stuff. 4. Sanitary test and also economical analysis will be conducted for the powdered products. B. Scope of the study 1. Production of seaweed powders Sargassum fulvellum growing in eastern coast and Sargassum patens C.A. in southern coast were used as the material for the powders. These algae, which have been not used for human consumption, were pulverized through the processes of washing, drying, pulverization, etc. 2. Nutritional experiments a. Chemical composition Proximate components (water, protein, fat, cellulose, sugar, ash, salt), minerals (calcium, phosphorus, iron, iodine), vitamins (A, $B_1,\;B_2$ niacin, C) and amino acids were analyzed for the seaweed powders. b. Animal feeding experiment Weaning 160 rats (80 male and 80 female rats) were used as experimental animals, dividing them into 16 groups, 10 rats each group. Each group was fed for 12 weeks on cereal diet (Wheat flour, rice powder, barley powder, potato powder, corn flour) with the supplementary levels of 5%, 10%, 15%, 20% and 30% of the seaweed powder. After the feeding the growth, feed efficiency ratio, protain efficiency ratio and ,organs weights were checked and urine analysis, feces analysis and serum analysis were also conducted. 3. Experimental cooking and acceptability test a. Several basic studies were conducted to find the characteristics of the seaweed powder. b. 17 kinds of Korean dishes and 9 kinds of foreign dishes were prepared with cereal flours (wheat, rice, barley, potato, corn) with the supplementary levels of 5%, 10%, 15%, 20% and 30% of the seaweed powder. c. Acceptability test for the dishes was conducted according to plank's Form. 4. Sanitary test The heavy metals (Cd, Pb, As, Hg) in the seaweed powders were determined. 5. Economical analysis The retail price of the seaweed powder was compared with those of other cereals in the market. And also economical analysis was made from the nutritional point of view, calculating the body weight gained in grams per unit price of each feeding diet. IV. Results of the study and the suggestion for application A. Chemical composition 1. There is no any big difference in proximate components between powders of Sargassum fulvellum in eastern coast and Sargassum patens C.A. in southern coast. Seasonal difference is also not significant. Higher levels of protein, cellulose, ash and salt were found in the powders compared with common cereal foods. 2. The levels of calcium (Ca) and iron (Fe) in the powders were significantly higher than common cereal foods and also rich in iodine (I). Existence of vitamin A and vitamin C in the Powders is different point from cereal foods. Vitamin $B_1\;and\;B_2$ are also relatively rich in the powders.'Vitamin A in ·Sargassum fulvellum is high and the levels of some minerals and vitamins are seemed4 to be some influenced by seasons. 3. In the amino acid composition methionine, isoleucine, Iysine and valine are limiting amino acids. The protein qualities of Sargassum fulvellum and Sargassum patens C.A. are seemed to be .almost same and generally ·good. Seasonal difference in amino acid composition was found. B. Animal feeding experiment 1. The best growth was found at.10% supplemental level of the seaweed Powder and lower growth rate was shown at 30% level. 2. It was shown that 15% supplemental level of the Seaweed powder seems to fulfil, to some extent the mineral requirement of the animals. 3. No any changes were found in organs development except that, in kidney, there found decreasing in weight by increasing the supplemental level of the seaweed powder. 4. There is no any significant changes in nitrogen retention, serum cholesterol, serum calcium and urinary calcium in each supplemental level of the seaweed powder. 5. In animal feeding experiment it was concluded that $5%{\sim}15%$ levels supplementation of the seaweed powder are possible. C. Experimental cooking and acceptability test 1. The seaweed powder showed to be utilized more excellently in foreign cookings than in Korean cookings. Higher supplemental level of seaweed was passible in foreign cookings. 2. Hae-Jo-Kang and Jeon-Byung were more excellent than Song-Pyun, wheat cake, Soo-Je-Bee and wheat noodle. Hae-Je-Kang was excellent in its quality even as high as 5% supplemental level. 3. The higher levels of supplementation were used the more sticky cooking products were obtained. Song-Pyun and wheat cake were palatable and lustrous in 2% supplementation level. 4. In drop cookie the higher levels of supplementation, the more crisp product was obtained, compared with other cookies. 5. Corn cake, thin rice gruel, rice gruel and potato Jeon-Byung were more excellent in their quality than potato Man-Doo and potato noodle. Corn cake, thin rice gruel and rice gruel were excellent even as high as 5% supplementation level. 6. In several cooking Porducts some seaweed-oder was perceived in case of 3% or more levels of supplementation. This may be much diminished by the use of proper condiments. D. Sanitary test It seems that there is no any heavy metals (Cd, Pb, As, Hg) problem in these seaweed Powders in case these Powders are used as supplements to any cereal flours E. Economical analysis The price of the seaweed powder is lower than those of other cereals and that may be more lowered when mass production of the seaweed powder is made in future. The supplement of the seaweed powder to any cereals is also economical with the criterion of animal growth rate. F. It is recommended that these seaweed powders should be developed and used as supplement to any cereal flours or used as other food material. By doing so, both saving of cereals and improvement of individual's nutrition will greatly be achieved. It is also recommended that the feeding experiment for men would be conducted in future.

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Seasonal Variation of the Quantity and Quality of Seston as Diet Available to Suspension-Feeders in Gosung and Kangjin Bays of Korea (고성만과 강진만에서 현탁물 섭식자에 유용한 입자물질 양과 질의 계절 변동)

  • LEE Pil-Yong;KANG Chang-Keun;CHOI Woo-Jeung;YANG Han-Seob
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.34 no.4
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    • pp.340-347
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    • 2001
  • Seasonal variation of the elemental and biochemical composition of the suspended particulate matter (SPM) was investigated in terms of quantity and quality of diets for suspension feeders from July 1999 to August 2000 in two coastal bay systems of Gosung and Kangjin Bays in Korea. No clear patterns in the seasonal variations of SPM concentration were found in these two bay systems. The results indicated that the seasonal variation of SPM could not be considered the variation of food available to suspension-feeders. The simultaneous peaks in chlorophyll a and biochemical components in summer indicated that the quantity of the particulate organic matter primarily depended on phytoplankton productivity. However, no correlation between chlorophyll a and biochemical components [particulate protein (PPr), carbohydrate (PCHO) and lipid] were found, indicating that other processes might also contribute to the particulate organic matter in the period when the phytoplankton biomass was low. High C: Chl a and C:N, and carbohydrate peaks during the autumn to spring period suggested that resuspension of surface sediments was a probable process to supply the particulate organic matter. The food material, represented by summing up the total quantity of three biochemical components, was highest in spring with minor peaks during the period from autumn to the next spring, The food index, calculated as the ratio of food material to total SPM, did not generally exceed $6\%$ with short peaks during the year. Therefore, nutritional quality of SPM in the bays are relatively poor than in other more productive coastal waters in the world. Our results confirm that the measurement of a single chemical variable cannot describe fully the nutritive value of the seston available to suspension-feeders as previously proposed, and the biochemical composition of SPM can provide effective information on its origin and nutritive Quality.

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Consumer Preference for Eggshell Color in Korea - Eggs from the Research of Developing Fowl Typhoid Resistant Strains - (난각색에 대한 한국 소비자 기호도 조사 -가금티푸스 저항성 계통 개발연구에서 생산된 계란을 중심으로-)

  • 이규희;한성욱;이봉덕;오봉국;김기석
    • Korean Journal of Poultry Science
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    • v.30 no.1
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    • pp.29-34
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    • 2003
  • It has been well documented that white egg layers are far more resistant to fowl typhoid than the brown egg layers. In Korea, however, most consumers prefer brown eggs to white ones. Therefore, a study was conducted to Produce fowl typhoid-resistant crossbred layers producing somewhat brown-colored eggs. Several crossbred strains were obtained from crossbreeding white egg lines (W) with brown egg lines (B). These crossbred layers (W${\times}$B) produced eggs with varying degrees of brown-colored shells between the white eggs obtained from W (White) and the brown eggs from B (Brown). Eggs from the peak stage of production were collected and their eggshell color values were measured. The mean eggshell color values of White and Brown were 81.9 and 36.4, respectively. Eggs from the crossbred lines (W${\times}$B) were collected, and their eggshell color values were measured to re-group these eggs according to their color. The mean eggshell color values of Trt-White, Middle, and Trt-Brown were 70, 60, and 50, respectively (Fig. 1). A total of 247 people living in Daejeon area, mainly housewives, took part in this survey. First, they were offered eggs with varying degrees of eggshell color in a paper egg-tray, together with a questionnaire. After they filled out the first questionnaire, they were instructed that the eggshell color has nothing to do with its nutritive value. In the second questionnaire, their preference on both eggshell color and price, i.e., purchasing will, were investigated. In the first questionnaire, the Brown (eggshell color lightness 36.4) were most preferred, and the Trt-white (eggshell color lightness 70) were least preferred. No statistical significance was detected between Brown and Trt-Brown, and White and Trt-White. In the second questionnaire, the trend was the same as in the first. Although no significant difference was found between Trt-Brown and Brown, however, the Trt-Brown were most preferred, surpassing the Brown. In conclusion, regardless of the nutritive values, the Korean consumers prefer brown eggs to white ones, and this trend could be changed gradually through consumer education.

Nutritive Value of Kluyveromyces fragilis and Candida utilis As Feed for Aquaculture (양식 사료로서 Kluyveromyces fragilis와 Candida utilis의 영양가)

  • LEE Sang-Min;KIM Joong Kyun;KIM Tae Jin;MIN Jin Gi;PARK Heum Gi
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.32 no.6
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    • pp.791-797
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    • 1999
  • This study was conducted in order to evaluate nutritive values of yeasts (Kluyveromyces fragilis and Candida utilis) according to growth stages (early log phase, log phase, stationary phase and death phase) and chemical treatment of their cell wall, Proximate, amino acids, fatty acids and nucleotides composition of the yeast samples was determined. Crude protein content was high in K. fragilis ($48\~59\%$) compared to C. utilis ($26\~43\%$). Crude lipid and fiber contents of the yeasts were below than $1.6\%$ and $3.3\%$, respectively. Conposition of aspartic acid, glycine, proline, leucine, Iysine and valine of K. fragilis were higher than those of C. utilis, and glutamic acid and arginine of C. utilis were higher than those of K. fragilis. Proximate and amino acids composition was not siginificantly influenced by growth stage of the yeasts. Major fatty acids of the yeasts in all growth stages were $C_{10-18}$. $C_{16-18}$ contents were relatively high in the early log or log phase and $C_{10-12}$ contents were relatively high in the stationary or death phase. However, n-3 highly unasturated fatty acids (C$\ge$20) in the all growth stages were not observed. This result indicated that these yeast strains could not be adequate as a dietary lipid source for marine fish. Composition of nucleotides and their related compounds (ATP ADP AMP, IMP and inosine) in the early log phase yeasts were lower than those in the log, stationary and death phase yeasts.

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Effect of Addition of Lactic Acid Bacteria and Chlorella on Nutritive Values and Quality of Italian Ryegrass-Hairy Vetch Silage (젖산균과 클로렐라 첨가가 이탈리안라이그라스-헤어리베치 사일리지의 사료가치 및 품질에 미치는 영향)

  • Choi, Ki Choon;Arasu, M. Valan;Ilavenil, S.;Park, Hyung Su;Jung, Min Woong;Kime, Ji Hye;Jung, Jeong Sung;Hwangbo, Soon;Kim, Won Ho;Lim, Young Chul
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.34 no.1
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    • pp.39-44
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    • 2014
  • This study was conducted to investigate the effect of the addition of lactic acid bacteria (LAB) and chlorella on the change of nutritive value, quality and microbes regarding the mixture silage of Italian ryegrass and hairy vetch (IRG-HV silage). The content of crude protein of IRG-HV silage in only the LAB treatment was not different as compared to the control. However, the content of crude protein significantly increased in the treatment of LAB with chlorella, compared to both the control and LAB treatments (p<0.05). Acid detergent fiber, neutral detergent fiber, total digestible nutrient and in vitro dry matter digestibility of IRG-Alfalfa silage were not significantly different in all treatments. Further, the pH of IRG-HV silage in only the LAB treatment was not different as compared to control, but decreased in both LAB and chlorella treatments (p<0.05). The content of lactic acid in the LAB treatment increased as compared to the control, and also significantly increased in the LAB treatment with chlorella (p<0.05). In addition, the number of LAB in LAB treatment increased as compared to the control, and significantly also increased in the LAB treatment with chlorella (p<0.05). Therefore, we suggest that IRG-HV silage improved with addition of both LAB and chlorella.

Nutritive Effects of Feeding Rice Diet Mixed with Barley and/or Millet on the Growth Rate and Biological Availability of Some Nutrients by Albino rats (보리와 속(粟)의 혼식(混食)이 성장기(成長期) 백서(白鼠)에 미치는 영양효과(營養效果))

  • Ha, C.J.;Hyun, K.S.;Han, I.K.
    • Journal of Nutrition and Health
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    • v.9 no.3
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    • pp.1-7
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    • 1976
  • This study was carried out to observe the nutritive effects of feeding rice diet and rice diet mixed with barley or millet, or both on the growth rate and biological availability of some nutrients by albino rats. The experimental diets were prepared on the basis of isocaloric and isonitrogenous containing 357 kcal of energy and 12g of protein per 100g of diet. The experimental animals weighing about 66g of both sexes were fed on 7 kinds of diets such as control diet, rice (100%) diet, rice (70%)+barley (30%) diet, rice (70%)+millet (30%) diet, rice (70%)+barley (20%)+millet (10%) diet, rice (70%)+barley (15%)+millet (15%) diet, and rice (70%)+barley (10%)+millet (20%) diet for 7 weeks. The results obtained are summarized as follows; 1. The gain in body weight was higher for barley and/or millet mixed with rice diet groups than rice diet group with no statistical difference. 2. Although there was no difference in the amount of food consumed by experimental groups, the food efficiency ratio was sightly higher for the miked diet groups than rice atone diet group. 3. The protein efficiency ratio was also higher for barley and millet miked with rice diet groups than rice diet group, although statistical significance was not found. 4. Apparent digestibility of protein of rice diet group was significantly (P<0.01) higher than any other diet group. Although there was no remarkable difference between mixed diet group was found, the apparent digestibility of protein tended to increase when rats were fed on the barley and millet mixed with rice diet. Apparent biological value (p<0.05) and net protein utilization (p<0.01) were also significantly higher for the groups fed mixed diet with barley and/or millet than rice diet group, and those for millet alone mixed diet were slightly lower. 5. The content of total nitrogen in the liver and of protein in serum were not significantly different among experimental groups. It may be concluded from the above results that an adequate supplementation of rice with other cereals and mixing ratio of other cereals to rice were important for the efficient utilization of protein in total diet.

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Predicting the Nutritional Value of Seafood Proteins as Measured by Newer In Vitro Model 2. C-PER and DC-PER of Marine Crustacea (수산식품 단백질 품질평가를 위한 새로운 모델 설정 2. 해산 갑각류의 C-PER 및 DC-PER)

  • RYU Hong-Soo;LEE Keun-Woo
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.19 no.3
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    • pp.219-226
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    • 1986
  • To confirm the application of a newer in vitro assays to determining the nutritional value of marine crustaceans (mainly shrimps and crabs), which have been considered to be highly nutritive depending on their levels of the essential amino acids and digestibility, their C-PERs and DC-PERs were determined and studied the factors influencing their in vitro results. Four species of seawater shrimps and 2 species of seawater crabs were used in this experiment. The in vitro digestibilities showed $83{\sim}86\%$ for raw shrimps and the trypsin indigestibile substrate content (TIS) was ranged from 1.32 to 3.33 mg/g solid expressed quantitatively as mg of purified soybean trypsin inhibitor. The smaller size of shrimps revealed a greater in vitro digestibility and a lower contents of TIS. It was noted that the in vitro digestibility of raw blue crab meat was around $85\%$ while boiled tenner crab meat showed $86\%$ or above, and the leg meat had the greatest in vitro digestibility in the various parts of crab meats. The poor in vitro digestibilities for shrimp's and crab's meat, compared with that of the other seafoods as noted in previous reports, suggest that the drop in pH, due to the change in their freshness during harvesting and frozen storage, resulted in underestimating their digestibilities using four-enzyme digestion technique. The lysine contents in all samples were higher than that of ANRC casein but they contained a slightly lower sulfur-containing amino acids than those in ANRC casein. But the other EAA, such as valine, tyrosine and phenylalanine, were found to be a half as little as that in casein and played a key-factor in calculation of C-PER or DC-PER. It was observed that the value of C-PER and DC-PER for all samples ranged from 2.1 to 2.4, and the predicted digestibilities showed $90\%$ or above in all samples. It was a different results from the fact that the animal proteins bear a higher values and predicted digestibilities than those of C-PER values. The lack of correlation between C-PER and DC-PER values is attributable to the fact that the lower content of valine, tyrosine and phenylalanine, and drop in pH owing to the changes of freshness in marine crustacea proteins. Therefore, if a newer in vitro digestion technique-which are taken into account the pH drop before digestion, TIS content and released free amino acids and/or peptides-developed, C-PER assays can provide more advantages in assessing the protein nutritional value of marine crustacea than any other in vitro assays.

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