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排序方式: 共有343条查询结果,搜索用时 15 毫秒
61.
Headed and gutted fresh or frozen and thawed cod (Gadus morhua L.) from the same net catch were hand filleted post rigor before carrying out small-scale salting trials. Fillets were heavy salted using three different methods introducing phosphate during injection, brining, or during pickle salting. For all salting methods, treatment with 0, 4.5, 9 or 18 g/L of the pyro and tri polyphosphate blend Carnal 2110 was carried out. Quality and chemical parameters were analyzed after 5 weeks and 6 ± 1 months of chilled storage of heavy salted fillets. 相似文献
62.
Pedro T. Pisa Edwige Landais Barrie Margetts Hester H. Vorster Christine M. Friedenreich Inge Huybrechts 《Critical reviews in food science and nutrition》2018,58(1):37-61
Objective: To carry out an inventory on the availability, challenges, and needs of dietary assessment (DA) methods in Africa as a pre-requisite to provide evidence, and set directions (strategies) for implementing common dietary methods and support web-research infrastructure across countries. Methods: The inventory was performed within the framework of the “Africa's Study on Physical Activity and Dietary Assessment Methods” (AS-PADAM) project. It involves international institutional and African networks. An inventory questionnaire was developed and disseminated through the networks. Eighteen countries responded to the dietary inventory questionnaire. Results: Various DA tools were reported in Africa; 24-Hour Dietary Recall and Food Frequency Questionnaire were the most commonly used tools. Few tools were validated and tested for reliability. Face-to-face interview was the common method of administration. No computerized software or other new (web) technologies were reported. No tools were standardized across countries. Conclusions: The lack of comparable DA methods across represented countries is a major obstacle to implement comprehensive and joint nutrition-related programmes for surveillance, programme evaluation, research, and prevention. There is a need to develop new or adapt existing DA methods across countries by employing related research infrastructure that has been validated and standardized in other settings, with the view to standardizing methods for wider use. 相似文献
63.
Obesity Impairs Oligopeptide/Amino Acid‐Induced Ghrelin Release and Smooth Muscle Contractions in the Human Proximal Stomach 下载免费PDF全文
64.
The objective of this research was to examine the effects of inbreeding in the population of Holstein cattle in the Walloon region of Belgium. The effects of inbreeding on the global economic index and its components were studied by using data from the genetic evaluations of February 2004 for production, somatic cell score (SCS), computed from somatic cell counts and type. Inbreeding coefficients for 956,516 animals were computed using a method that allows assigning an inbreeding coefficient to individuals without known parents. These coefficients were equal to the mean inbreeding coefficient of contemporary individuals with known parents. The significance of inbreeding effects on the different evaluated traits and on the different indexes were tested using a t-test comparing estimated standard errors and effects. The inbreeding effect was significantly different from zero for the vast majority of evaluated traits and for all of the indexes. Inbreeding had the greatest deleterious effects on production traits. Inbreeding decreased yield of milk, fat, and protein during a lactation by 19.68, 0.96, and 0.69 kg, respectively, per each 1% increase in inbreeding. The regression coefficient of SCS per 1% increase in inbreeding was +0.005 SCS units. The inbreeding depression was thus relatively low for SCS, but inbred animals had higher SCS than non-inbred animals, indicating that inbred animals would be slightly more sensitive to mastitis than non-inbred animals. Estimates of inbreeding effects on evaluated type traits per 1% increase were small. The most strongly affected type traits were chest width, rear leg, and overall development on a standardized scale. For several type traits, particularly traits linked to the udder, the estimates suggested a favorable effect of inbreeding. The global economic index was depressed by around 6.13 € of lifetime profit per 1% increase in inbreeding for the Holstein animals in the Walloon region of Belgium. 相似文献
65.
66.
Beatrice Ekesa Marie Poulaert Mark W. Davey Judith Kimiywe Inge Van den Bergh Guy Blomme Claudie Dhuique-Mayer 《Food chemistry》2012
Bananas and plantains (Musa spp.) constitute an important component of the diet in Africa. Substantial levels of provitamin A carotenoids (pVACs) in Musa fruit have been reported, but the bioaccessibility of these pVACs remains unknown. In this study, we used an in vitro digestion model to assess the bioaccessibility (i.e. the transfer into micelles) of pVACs from boiled bananas and derived dishes using the Eastern Democratic Republic of Congo as a study context. In particular, the effect of different food ingredients added to boiled bananas on pVAC’s bioaccessibility was studied. The bioaccessibility of all-trans β-carotene ranged from 10% to 32%, depending on the food recipes, and was modified, particularly when pVACs-rich ingredients (palm oil/amaranth) were added. Efficiency of micellarization of all-trans β-carotene was similar to that of all-trans α-carotene and depended on the cultivar (Musilongo, plantain type, 16%; Vulambya, East African cooking type, 28%), while that of the 13-cis isomer was higher (21–33.5%). Taking into account bioaccessibility, the estimated vitamin A activity was significantly different across the different Musa-based dishes tested. Results are discussed in terms of recommendations to help reduce vitamin A deficiency in Musa-dependent African communities. 相似文献
67.
Ferdinand Radler und Inge Schönig 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1978,167(3):165-170
Zusammenfassung Insgesamt 116 verschiedene, überwiegend aus Wein isolierte Stämme von Milchsäure-bakterien der GattungenLactobacillus, Leuconostoc, Pediococcus undStreptococcus wurden auf die Fähigkeit zur Verwertung von Gluconsäure untersucht. Bis auf einzelne Ausnahmen wurde Gluconsäure von denLactobacillus-Arten, die den UntergattungenStreptobacterium undBetabacterium angehörten, und der Mehrzahl derLeuconostoc-Stämme vergoren. VonPediococcus wurde Gluconsäure nicht abgebaut. Bei wachsenden Kulturen und ruhenden Zellen vonLactobacillus brevis, Lactobacillus casei undLeuconostoc oenos waren die Endprodukte des Gluconsäureabbaus Milchsäure, Essigsäure, Äthanol und CO2. Milchsäure entsteht aus Gluconsäure in annähernd äquimolaren Mengen. In einem aus Wein und Hefeextrakt bestehenden Medium (pH 3,5) wurden 0,5 g Gluconsäure und 4,5 g Äpfelsäure je 1 vonLactobacillus brevis undLeuconostoc oenos vollständig abgebaut.
Fermentation of gluconic acid by lactic acid bacteria isolated from wine
Summary The fermentation of gluconic acid was investigated in 116 different strains of lactic acid bacteria belonging to the generaLactobacillus, Leuconostoc, Pediococcus andStreptococcus. Most of the strains were isolated from wine. Gluconic acid was fermented by nearly all species of the genusLactobacillus (belonging to the subgeneraStreptobacterium andBetabacterium and by most strains ofLeuconostoc. The pediococci did not ferment gluconic acid. Growing cultures and resting cells ofLactobacillus brevis, Lactobacillus casei andLeuconostoc oenos formed lactic acid, acetic acid, ethanol and CO2 from gluconic acid. Lactic acid was formed in about equimolar amounts from gluconic acid.Lactobacillus brevis andLeuconostoc oenos metabolised completely 0.5 g of gluconic acid and 4.5 g of malic acid per liter when cultured in a medium consisting of wine and a small amount of yeast extract (at pH 3.5).相似文献
68.
Dietary exposure to benzoxazinoids enhances bacteria‐induced monokine responses by peripheral blood mononuclear cells 下载免费PDF全文
69.
Patricia Semaan Abraham Zahran Inge Schlapp-Hackl Ali R. Tehrani-Bagha Samir Mustapha 《应用聚合物科学杂志》2024,141(14):e55180
Epoxy polymers are commonly utilized in structural applications due to their high bearing capacity and excellent chemical resistance. However, their inherent brittleness poses a significant challenge for their use in high shock and fracture strength products. To address this shortcoming, fillers can be incorporated into the polymer during preparation. In this study, we aimed to investigate the effect of incorporating cellulose-based fillers, namely cellulose nanocrystals (CNCs) and microcrystalline cellulose (MCC), on the mechanical properties of epoxy polymer composites. The study evaluated the impact of various factors, including filler concentration, particle size, and moisture content, on the mechanical properties of the composites. The results demonstrated that the incorporation of CNC or MCC powders at concentrations below 5% could enhance the mechanical properties of the resulting epoxy composites without adversely affecting their surface and thermal properties. The maximum tensile strength and fracture toughness of the filler-based epoxy composites were achieved at 2 and 4 wt% for CNCs and MCC, respectively. CNCs with a smaller particle size distribution were found to be much more effective than MCC in improving the mechanical properties of the epoxy composites. Furthermore, utilizing dried fillers resulted in a higher improvement in tensile strength, which was achieved at lower filler concentrations. 相似文献
70.
Desalination of a brick by application of an electric DC field 总被引:1,自引:1,他引:0
Salts in masonry can cause various problems as decay of the masonry itself, lost adhesion of plaster and hygroscopic moisture.
Chlorides are among the most common building salts and the present paper is focused on removal of chlorides from a brick in
an applied electric field as a step towards developing an electrochemical desalination method for brick masonry. Experiments
were conducted in laboratory scale with one type of bricks that were contaminated with either NaCl or KCl through submersion
in salt solutions prior to application of current. It was seen that NaCl was slower supplied to the brick during submersion
and slower removed in the applied electric field than KCl. This indicates that the removal rate of chloride depends on the
associated cation and this must be taken into account when desiding the duration of full scale actions. The electrochemical
desalination was very efficient and 99% removal of chloride was obtained. The final concentration in the brick after treatment
was less than 10 mg Cl/kg and this concentration is unproblematic. When low salt concentrations were reached during the electrochemical
treatment, electroosmotic dewatering of the brick started, showing that electroosmotic dewatering occurs at low ionic concentrations. 相似文献