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131.
Pooled serum samples from 3802 Australian residents were analyzed for four perfluoroalkylsulfonates, seven perfluoroalkylcarboxylates, and perfluorooctanesulfonamide (PFOSA). Serum was collected from men and women of five different age groups and from rural and urban regions in Australia. The highest mean concentration was obtained for perfluorooctane sulfonate (PFOS, 20.8 ng/mL) followed by perfluorooctanoic acid (PFOA, 7.6 ng/mL), perfluorohexane sulfonate (PFHxS, 6.2 ng/mL), perfluorononanoic acid (PFNA, 1.1 ng/mL), and PFOSA (0.71 ng/mL). Additional four PFCs were detected in 5-18% of the samples at concentrations near the detection limits (0.1-0.5 ng/mL). An increase in PFOS concentration with increasing age in both regions and genders was observed. The male pool levels of some of the age groups compared to females were higherfor PFOS, PFOA, and PFHxS. In contrast, PFNA concentrations were higher in the female pools. No substantial difference was found in levels of PFCs between the urban and rural regions. The levels are equal or higher than previously reported serum levels in Europe and Asia but lower compared to the U.S.A. These results suggest that emissions from production in the Northern Hemisphere are of less importance for human exposure.  相似文献   
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Twenty-one strains of the genus Lactobacillus and the genus Pediococcus, isolated from Polish raw fermented meat products, were examined for the potential probiotic properties: resistance to simulated gastric and intestine conditions, safety assessment, and antimicrobial properties. Strains were resistant to gastric enzymes and low pH (3–6 log CFU/mL decrease) and intestinal enzymes and bile salts (1–3 log CFU/mL decrease). Most strains were resistant to gentamycin, streptomycin, vancomycin, tetracycline, ciprofloxacin, and kanamycin. Three of them (Lb. brevis BAL1, BAL10, and KL5) produced β-glucuronidase, which excludes them from qualifying as safe. Seven strains had the ability to produce bacteriocins or bacteriocin-like substances. Overall, strains Lb. brevis SCH6, Pd. pentosaceus BAL6, and KL14 revealed selected superior characteristics (resistance to the gastrointestinal conditions, safety assessment, and antimicrobial properties) as compared to the other LAB strains investigated, which made them a viable bioprotective culture that can be inoculated in raw fermented meat products as starter cultures.  相似文献   
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The objective of this study was to evaluate the potential of double wall material combinations, using legume protein (soy protein isolate and pea protein isolate) in combination with wheat dextrin soluble fiber or trehalose, as alternative materials for microencapsulation of flaxseed oil by spray drying. The obtained preparations, with oil content of 35%, were fine and difficult flowing powders, regardless of their composition. The 1% addition of silica to the powders significantly reduced their cohesiveness and improved their flowability. The efficiency of microencapsulation, calculated based on oil fat content, ranged from 62 to 98% and was higher in the powders with trehalose and in the powders containing soy protein. Effective protection against oxidation of microencapsulated oil was achieved in the protein-trehalose matrix, especially in the case of the vacuum-packed powders with pea protein during storage at refrigeration temperature. Replacing trehalose with soluble fiber enabled formation of powders less susceptible to caking under conditions of increased humidity, but it resulted in decreased microencapsulation efficiency. The combination of pea protein/carbohydrate resulted in the formation of microcapsules with porous structure, especially in the system with soluble fiber. With time, the structure of the primary emulsions and those reconstituted from powders containing pea protein changed from liquid to greasy and paste-like.  相似文献   
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The present study applied indicator value analysis as a novel approach to estimate honey authenticity: microscopic indicators of honey origin were identified based on the distinct fungal content of honeys from different sources. The abundance and the IndVal index of 34 selected fungal spore types were quantified in 82 melissopalynological honey samples originating from various honeydew (Pinus, Abies) or nectar sources using multivariate statistical approaches. A dissimilarity matrix of honey samples was obtained by computing Bray-Curtis coefficients, and the distances were visualized using non-metric multidimensional scaling. K-means clustering was applied to sample coordinates to create a classification based on the frequency of selected fungal taxa. Strikingly, the resulting clusters were on a high level of agreement with the melissopalynological or geographical classification of samples. Various fungal taxa were shown to characterize groups of honey samples with a significant indicator value: floral honeys (Metschnikowia reukaufii), Pinus honeydew honeys (Capnobotrys sp., Antennatula sp.), Abies honeydew honeys from Greece (staurospore and scolecospore types) and honeydew honeys from Italy (Tripospermum spp. and Excipularia fusispora). Having revealed that the mere presence of distinct fungal taxa can indicate differences in the botanical and geographical source of honeys, the present findings encourage the confirmation of honey origin also by recording the occurrence of given honeydew elements during routine melissopalynological analysis.  相似文献   
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Stratification and nutrient loading are two primary factors leading to hypoxia in coastal systems. However, where these factors are temporally correlated, it can be difficult to isolate and quantify their individual impacts. This study provides a novel solution to this problem by determining the effect of stratification based on its spatial relationship with bottom-water dissolved oxygen (BWDO) concentration using a geostatistical regression. Ten years (1998-2007) of midsummer Gulf of Mexico BWDO measurements are modeled using stratification metrics along with trends based on spatial coordinates and bathymetry, which together explain 27-61% of the spatial variability in BWDO for individual years. Because stratification effects explain only a portion of the year-to-year variability in mean BWDO; the remaining variability is explained by other factors, with May nitrate plus nitrite river concentration the most important. Overall, 82% of the year-to-year variability in mean BWDO is explained. The results suggest that while both stratification and nutrients play important roles in determining the annual extent of midsummer hypoxia, reducing nutrient inputs alone will substantially reduce the average extent.  相似文献   
140.
燕麦片加工品质评价及其品种相关性研究   总被引:2,自引:6,他引:2  
拟通过燕麦品种间品质性状的差异来寻求燕麦片加工品质的客观评价方法,并从中筛选出适宜加工燕麦片的优良品种.结果显示,燕麦品种间在粗脂肪、粗纤维、千粒重及β-葡聚糖含量等理化指标上存在较大变异;燕麦片的理化和感官评价指标中以汤汁黏度、口感、色泽等指标对产品整体品质影响最为显著.从燕麦片的营养和食用品质综合考虑,从34个国产燕麦品种中筛选出适宜加工燕麦片的5个优质品种-坝莜1号(河北产)、白燕2号(山西产)、坝莜3号、张莜1号、定莜2号.  相似文献   
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