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221.
Bilberries (Vaccinium myrtillus L.) and their major polyphenolic constituents, anthocyanins, have preventive activities inter alia against colon cancer and inflammatory bowel diseases. However, anthocyanins are sensitive to environmental conditions; thus their bioavailability in the gastrointestinal tract is an important determinant of their in vivo activity. In the study reported here, the potential benefits of encapsulating an anthocyanin rich bilberry extract (BE) on anthocyanin stability were investigated. Nonencapsulated BE and three different BE loaded microcapsule systems were incubated in simulated gastric fluid (SGF) and fed state simulated intestinal fluid (FeSSIF). After exposure to these media, released anthocyanins were identified and quantified by HPLC with UV/Vis detection. Although a rapid release of anthocyanins was observed within the first 20 min, encapsulation of anthocyanins doubled the amount of available anthocyanins after 150 min of incubation. These results illustrate the ability of encapsulation to inhibit early degradation of anthocyanins in the intestinal system.  相似文献   
222.
In this study, we investigate a technological approach to reduce the sodium content of bread whilst retaining its sensory profile by creating taste contrast using encapsulated salt. We demonstrate that sensory contrast in bread induced by encapsulated salt can enhance saltiness and allows for a salt reduction of up to 50% while maintaining saltiness intensity. The magnitude of the saltiness enhancement depends on the size of the salt encapsulates. Small encapsulates lead to small concentration gradients of salt which do not affect saltiness intensity and consumer liking. Large encapsulates lead to large concentration gradients which enhance saltiness intensity significantly and reduce consumer liking. To achieve maximum salt reduction while maintaining saltiness and liking of the bread, the dimensions of the encapsulated salt particles need to be optimized. Taste contrast is a technology to modulate taste perception and to create sodium reduced products while retaining their saltiness intensity and consumer liking.  相似文献   
223.
ABSTRACT

Experts in the oyster supply chain (farmers, retailers, and gourmet chefs) in The Netherlands have suggested that the European flat oyster (Ostrea edulis) has superior sensory qualities compared to the Pacific cupped oyster (Crassostrea gigas). However, scientific evidence is lacking. The aim of this study was to evaluate consumer preferences for these two oyster species and to determine the sensory properties of both species by consumers. Two-alternative forced choice tests were performed with the oysters involving a panel of 74 naïve consumers. No significant differences in preferences between the oyster species were observed by the consumers. Nine sensory attributes of both oyster species were evaluated. Consumers did not observe significant differences between species in the sensory attributes: overall odor intensity, sea odor, mud odor, sweetness, pungency, and firmness. The Pacific cupped oyster was perceived as significantly saltier and more intense in greenness than the European flat oyster. We concluded that only a few sensory properties of the European flat oyster and the Pacific cupped oyster are perceived as being different by untrained consumers.  相似文献   
224.
Today's modern Dent × Flint maize (Zea mays L. ssp. mays) hybrids have a high yield potential but often lack satisfying early vigour under typical low spring temperatures of temperate latitudes. Maize was introduced into Europe already in the 16th century and until the 1950s, landraces evolved and adapted well to various geographically restricted and climatically marginal regions in Europe. Therefore, the objective of this study was to assess representatives of the large pool of Swiss Flint maize landraces for their early vigour under cool conditions in the field. A set of 17 landrace accessions were tested for 2 years at sites on the Swiss plateau (450 and 550 m a.s.l.) and in the foothills of the Swiss Alps (830 and 870 m a.s.l.). Plant emergence (PE), emergence index (EI), the efficiency of the photosystem II (Fv/Fm), leaf greenness (SPAD) and plant dry weight at the three- and six-leaf stages (DW3P, DW6P) were measured.  相似文献   
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A viral epidemic associated with the Cherry leaf roll virus (CLRV) has emerged in Betula species in Fennoscandia, exhibiting quick and effective spread during the last 15 years. A population genetics approach is chosen in order to characterise the virus diversity and the sources of genetic variation aiming to investigate the epidemiology of the pathogen. In a CLRV population from Rovaniemi urban parks and a population that occurred after infecting young Betula seedlings with scions from the original Finnish trees, the genetic diversity is found to be remarkably high, mixed infections by CLRV variants from different phylogenetic groups are detected in single trees, while recombination is evidenced to occur. The estimated genetic variability is high and the CLRV haplotypes detected exhibit clear clustering and belong to different phylogenetic groups. The structure of the viral population reveals a pathogen with high evolutionary potential assumed to carry on its effective spread.  相似文献   
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Proteomics is currently tested as a complementary tool for the safety assessment of genetically modified (GM) crops. Understanding the natural variability of the proteome is crucial for the interpretation of biological differences between transgenic and nontransgenic parental lines. The natural variation of seed protein profiles among a set of 12 Arabidopsis thaliana ecotypes was determined by utilizing two-dimensional electrophoresis (2DE). The total number of different resolved protein spots found among the 12 ecotypes was 931 with a range of 573 (Mt-0) to 653 (Condara) in any one ecotype. Although the ecotypes were grown side-by-side in an environmentally controlled growth chamber, almost half of the resolved spots varied with respect to their presence/absence, and 95% of the spots present in all ecotypes varied in spot quantity (2-53-fold). In the evaluation of unintended effects of genetic modification, it is concluded that the experimental design must account for existing natural variability, which, in the case of the expressed proteome, can be substantial.  相似文献   
230.
To determine the prevalence of Anaplasma phagocytophilum in dogs in Germany serum samples from 1124 dogs that were under suspicion of having anaplasmosis were examined. The samples were tested by an indirect immunofluorescence test (OFT) for antibodies to A. phagocytophilum. The geographical origin of positive cases were analysed with an geographic information system. Antibodies to A. phagocytophilum were found in 563 (50.1%) of the tested dogs. 166 dogs came from Saarland, 161 from North Rhine-Westphalia, 134 from Baden-Wuerttemberg, 33 from Bavaria, 22 from Rhineland-Palatinate, 11 from Hamburg, 10 from Brandenburg, 9 from Lower Saxony, 8 from Hesse and Berlin respectively and 1 from Schleswig-Holstein. Clinical signs and laboratory findings of 26 seropositive dogs were analysed. Those dogs showed a low haematocrit, thrombocytopenia and leucocytoses as well as higher values for alkaline phosphatase, ALAT und bilirubin. The clinical signs were lameness in 13 dogs, lethargy in 5, and uveitis in 3 dogs. Rhinitis and lymphadenopathy was found in 2 dogs and retinal detachment with blindness in 1 dog.  相似文献   
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