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1.
Methyl linoleate was heated for 10 hrs. at 300°C, in the absence of air and fractionated by alembic distillation and urea adduct-formation. Intestinal absorptions of the urea adduct-forming monomeric nonadduct-forming monomeric, and dimeric fractions were determined. It was found that dimers were half as well absorbed as the monomers. When fed to rats, dimers were better accepted and exhibited some toxicity symptoms different from the non-adduct-forming monomers. The dimers caused diarrhea, irritability, and loss of hair during the early period of administration. The nonadduct-forming monomers were lethal and produced an increase in liver weight. Both fractions depressed growth. With the technical assistance of Oscar giacomantone and Perla Mordujovich.  相似文献   

2.
The chemical and biological properties of poppy seed (Papaver somniferum) were studied to evaluate its possible role as a complement to or replacement for rapeseed in Sweden. A white variety of the seed contained 40% crude oil and 27% protein (N × 6.25), while a blue variety contained 33% oil and 21% protein. The amino acid composition of the two varieties were similar with chemical score values of 60 and 66, respectively. A meal was prepared by hydraulic pressing at room temperature. The protein efficiency ratio for this meal in rats was 2.34. A protein concentrate was prepared from the poppy seed meal by alkaline water extraction followed by iso-electric precipitation of protein. The freeze-dried precipitate contained 70% protein and 18% fat. Available lysine was the limiting amino acid in the protein concentrate.  相似文献   

3.
Peanut, sesame and coconut oils were heated at 270C for 8 hr, in an open iron pan. These fats were fed to albino rats at 15% level in otherwise adequate diets. All rats fed heated fats showed a growth depression. Livers of rats receiving heated oil were congested and showed extensive periportal fatty infiltration. Rats on heated peanut oil showed i) reduced B-vitamin storage in the liver, ii) increased glucose and cholesterol levels in the blood and iii) a disruption in the digestion and absorption of carbohydrates.  相似文献   

4.
Nutritive value of shellfish consumed in Chile   总被引:1,自引:0,他引:1  
The purpose of the present study was to determine the protein quality and digestibility of shellfish commonly consumed in Chile, and to estimate its contribution to the protein needs of the Chilean population. The shellfish studied were chorito (Mytilus edulis chilensis), macha (Mesodesma donacium), loco (Concholepas concholepas), cholga (Aulacomya ater), erizo (Loxechinus albus) and almeja (no specific variety). The NPU method was used to determine protein quality. The percentage of protein adequacy for adult rations was calculated according to FAO/WHO 1973. The contribution of shellfish to the protein availability according to the family income of the Santiago population, was also calculated. Most of the shellfish presented NPU values of about 70; the lowest values were found for loco (54.9) and macha (63.3). The apparent and true digestibility gave an average of 83.6 and 90.4, respectively. The percentage of protein adequacy of habitual rations ranged between 27% (erizo) and 58% (loco). The availability of shellfish protein in relation to total protein increased from 0.4 to 2.5% when income increased. It is concluded therefore, that shellfish protein is, in general, of good quality. Nevertheless, it might be considered of poor influence insofar as fulfilling the protein needs of the population studied, whatever its socioeconomic level.  相似文献   

5.
Defatted seed cake ofCleome viscosa was analysed for protein, amino acids, vitamins and minerals. It was found to be a fairly good source of protein and other nutrients. The most limiting amino acid of the protein in the defatted seed cake was tryptophan. Like otherCapparidaceous plants, seeds ofCleome viscosa contained thioglucosinolates. The concentration of which in defatted seed cake before and after detoxification was 3 and 0.12 mg per 100 g. Except for the loss of B-complex vitamins, on detoxification the nutrient composition of the defatted cake remained unaltered. Rats fed diets based on defatted cake containing the toxic compounds lost weight, but those fed detoxified cake showed improved growth. However, the relative protein value (RPV) of the processed cake was poor and suggested the presence of other antinutritional factors.  相似文献   

6.
明胶的食用及其营养价值   总被引:2,自引:2,他引:0  
<正> 食品是保持人们正常生长、发育、生活,保持有足够能量进行社会劳动的物资基础,是人类生存的能源。在某种意义上来说,食品工业是永恒的工业。现在世界上大约有43亿人口,到本世纪末将要增加到60亿。要养活比现在多三分之一的人口,首先要研究的就是如何开发可食资源。  相似文献   

7.
Comparative evaluation of plant growth promoting rhizobacteria viz. Azospirillum brasilense, Azotobacter vinelandii Khsr1 and chemical fertilizers was made on growth, protein, and oil yield as well as quality of canola (Brassica napus L.) cv. Rainbow. The A. brasilense and A. vinelandii were applied as seed inoculation at 106 cells/mL. The recommended doses of urea (150 kg/ha) and diamonium phosphate (180 kg/ha) were applied as sources of chemical fertilizers. First dose of chemical fertilizers was applied at the time of sowing while other three doses were applied at 45 days interval. The chemical fertilizers were highly effective in increasing leaf chlorophyll content, number of branches per plant, number of siliqua per branch, number of seeds per siliqua, and total seed yield. A. brasilense treatment increased the leaf and seed protein content (32 and 21%) as well as seed size as measured by % increase in 1000 seed weight. A. vinelandii treatment resulted in significant increase (4%) in seed oil contents but the glucosinolate and erucic acid (C22:1) contents of oil was decreased significantly. Maximum oleic acid (C18:1) content was found in seed oil of A. vinelandii treatment; whereas, significantly higher linolenic acid (C18:3) content was recorded in A. brasilense treatment. It is inferred from the present investigation that A. brasilense and A. vinelandii could be highly effective in improving yield and nutritive value of canola oil.  相似文献   

8.
9.
发掘过磷酸钙的潜在价值 彰显其多功能特性   总被引:1,自引:0,他引:1  
介绍过磷酸钙的多种营养元素含量、特性及其农化作用;提出过磷酸钙是主要的硫肥、钙肥,以及复混肥的母料;分析生产、使用过磷酸钙的潜在价值,展望了过磷酸钙的前景,并为过磷酸钙的生产提出建议。  相似文献   

10.
This paper deals with the development of a food for infants and young children based upon a mixture of 27.5% wheat flour, 20% sweet lupin flour and 20% powdered milk (GL) (18% fat content) with added vitamins and minerals. The blend of wheat and lupin flour was processed in an extrusion-cooker (Wenger X 25) before mixing with the other ingredients. The proximate chemical analysis performed on the wheat-lupin-milk blend (LTL) showed 18.7% protein and 12.5% fat with a calculated caloric value of 427 kcal/100 g. Amino acid analysis indicated a deficiency of methionine + cystine and of threonine in the blend. Nevertheless, studies with rats on the biological quality of the protein, such us protein efficiency ratio and apparent digestibility, revealed that this blend was as good as the reference diet (powdered egg). It is therefore felt that the LTL blend may be a useful substitute in food programs directed to infants and school children.  相似文献   

11.
Rapid synthesis of fatty acid esters for use as potential food flavors   总被引:1,自引:0,他引:1  
Lipase-catalyzed esterification has been performed in hexane to generate novel mixtures of fatty acid esters from specially chosen combinations of fatty acids and alcohols. By varying the alcohol and enzyme compositions in the enzymatic reactions, different ester mixtures were produced, which were further purified and analyzed for ester composition by gas chromatography-mass spectrometry. Depending on the combination of alcohols and enzymes used, the final ester mixture exhibited significant compositional variation. These mixtures could be manipulated at the synthesis step, thereby enabling a high degree of product control. Such manipulation over enzyme-catalyzed ester synthesis in mixtures may be useful in the preparation of ester flavors for use in the food industry.  相似文献   

12.
Lipase-catalyzed esterification has been performed in hexane to generate novel mixtures of fatty acid esters from specially chosen combinations of fatty acids and alcohols. By varying the alcohol and enzyme compositions in the enzymatic reactions, different ester mixtures were produced, which were further purified and analyzed for ester composition by gas chromatography-mass spectrometry. Depending on the combination of alcohols and enzymes used, the final ester mixture exhibited significant compositional variation. These mixtures could be manipulated at the synthesis step, thereby enabling a high degree of product control. Such manipulation over enzyme-catalyzed ester synthesis in mixtures may be useful in the preparation of ester flavors for use in the food industry.  相似文献   

13.
简述了胎脂的组成和对皮肤的保护作用,综述了国内外学者对天然胎脂的研究现状,总结了天然胎脂对胎儿皮肤的保湿、抗菌抗感染、p H调节和表皮屏障维护功能及作用机理,阐述了胎脂对保护胎儿皮肤并保障胎儿皮肤的健康生长发育具有有益作用,提出了植物仿生胎脂的概念并对其在第4代化妆品——仿生化妆品中应用的可能性进行了展望。  相似文献   

14.
This study was an attempt to determine the nutritional value of diets based on mixtures of manioc and cowpea flours. The proportions analyzed were 87/13, 70/30 and 50/50, respectively. The effect of supplementing these diets with methionine was also investigated. The nutritional value of the diets was evaluated using as a basis the percentage of utilizable protein. Findings revealed that the protein was best utilized when the percentages of manioc and cowpea flours were 50/50, with significant differences observed among the proportions analyzed. In contrast, no significant differences were observed with methionine supplementation to diets of manioc and cowpea flours mixed in the proportion of 87/13. However, when the proportions were 70/30 and 50/50, the addition of methionine induced significant differences, with the highest protein value in both mixtures. It was also observed that the percentage of utilizable protein increased as the proportions of cowpea in the diets also increased.  相似文献   

15.
16.
Xylanase from Aspergillus foetidus MTCC 4898 was purified using ammonium sulphate fractionation followed by ion exchange and gel permeation chromatography with 12.26-fold purity and 29.9% recovery. Purified xylanase was found to be 29.9 kDa. Optimum temperature and pH for xylanase activity of purified xylanase were found to be 50 °C and 5.3 respectively. Presence of additives like polyethylene glycol, sodium azide, Tween 80, KCl and NaCl increased the stability of purified xylanase by 35, 29, 28, 32 and 43% respectively at 50 °C after 180 min. Kinetic parameters like Km and Vmax were found to be 4 mg/ml and 7288 μmol/mg/min respectively. The purified xylanase was found to be an endoxylanase as it produced only xylooligosaccharides (XOS) from birchwood xylan. Production of XOS was carried out from xylan extracted from agro-residues using β-xylosidase free xylanase. Maximum yield of XOS was 7.28 ± 0.14 mg/ml and 4.52 ± 0.21 mg/ml from wheat straw xylan and rice straw xylan respectively. XOS mixture was suitable for food industry looking at its high thermal stability at low pH. Prebiotic effect of XOS was evaluated by in vitro fermentation of XOS using known probiotic strains of Bifidobacterium spp.  相似文献   

17.
Polypropylene (PP) was modified by radical grafting of acrylic acid (AA) in the melt by using dicumyl peroxide (DCP) as initiator. To reach a high grafting degree (GD) without substantially modifying PP‐chain structure, a few runs were carried out by employing butyl 3‐(2‐furanyl)propenoate (BFA), which is a coagent able to preserve the molecular weight (MW) of PP macromolecules in the presence of radical grafting reagents. All the samples were extracted with selective solvents to remove unreacted chemicals and free poly(acrylic acid) (PAA), and the GD was accurately determined by using the FTIR methodology. The GD ranged from 1.51 to 4.67 mol %. High‐temperature size permeation chromatography analysis was used to evaluate MW behavior, confirming the control exerted by the presence of BFA on the degradation reactions. DSC, TGA, and SEM analyses were performed to analyze the chemical modification effects on the polymer products' thermal and morphological properties. Finally, selected samples, with a particle size distribution in the range 100–850 μm, were tested as metal ion adsorption resins. Al(III), Cr(III), Zn(II), Cd(II), Pb(II), and Hg(II) were studied, and the highest adsorption efficiency values (in percentage) were obtained for Al(III) (15–20%) and Hg(II) (25–30%). © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009  相似文献   

18.
The Atriplex lampa, chenopodiáceae, is a very abundant bush in the arid and semiarid regions of our Province. This work was undertaken to characterize from the chemical point of view, both the fresh leaves and the protein concentrate (PC) obtained from them. A second purpose was to determine the biological value of the protein, and to evaluate its capacity as a complement to wheat flour (WF). Through this study, the leaf was shown to have a high content of ashes, sodium, potassium and silica, what accounts for its low palatability. The PC obtained has a protein concentration of 59.37 g/100 g and its biological value is limited by the sulfur amino acids, with a chemical score of 85.70. Since the protein is poorly utilized, this results in a relatively low value of its net protein utilization (NPU), a fact which may be attributed to its low true digestibility. The studies on the complementary effects of PC on WF were made at three levels, i.e., 30, 50 and 60%, respectively. The results revealed that the best complementation, measured by the nitrogen utilization, happened to be when 50% of the protein contribution was provided by the A. lampa protein concentrate.  相似文献   

19.
20.
Two protein mixtures, A and B, based on sweet lupine, wheat flour and dried skim milk powder were formulated, bearing in mind the chemical and nutritional standards set by the National System of Health Services for protein mixtures used through the National Program of Complementary Feeding (PNAC) for preschool children. Both formulas contained 12% of sweet lupine flour, but they differed in their skim milk content, which was 15% in mixture A, and 10% in mixture B. Taking as reference value a content of 2% moisture, formula A contains 17.6% protein and mixture B, 16.4%, with a caloric content of 420 kcal/100 g for both of them. The amino acid score was 0.80 for both mixtures. The biological quality of the proteins of A and B, measured as protein efficiency ratio (PER), was 2.2 and 2.1, respectively. These values are not statistically different, although they are lower than the value of 2.5 obtained for casein (p less than 0.01).  相似文献   

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