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11.
Johannes Kahl Nicolaas Busscher Wolfgang Hoffmann Gaby Mergardt Ingrid Clawin-Raedecker Christian Kiesner Angelika Ploeger 《Food Analytical Methods》2014,7(7):1373-1380
Crystallization with additives is developed on milk samples from different processing treatments. Performance tests are carried out based on structure analysis of the crystallization patterns. Crystallization with milk as additive is applied following changes in milk after different processing treatments. When an aqueous cupric chloride dihydrate solution crystallizes in the presence of milk as additive, specific patterns emerge, which can be evaluated by image analysis. Milk samples were heated and homogenized in a pilot plant and characterized by various parameters. Furthermore, milk samples from the market were tested. Patterns from milk after heat treatment and homogenization are significantly different from those derived from untreated milk. The experiments could be reproduced for other milk samples, on different days and in another laboratory. 相似文献
12.
Brietzke Adrian Pham Xuan Rebecca Dettmann André Bullinger Angelika C. 《Forschung im Ingenieurwesen》2021,85(2):517-526
Forschung im Ingenieurwesen - The enjoyment and usage of highly automated vehicles might be reduced by motion sickness. This study addresses the influencing factors of dynamic stimulation, visual... 相似文献
13.
Helmut Brandl Claudia Fricker-Feer Dominik Ziegler Jyotshna Mandal Roger Stephan Angelika Lehner 《Journal of dairy science》2014
Airborne communities (mainly bacteria) were sampled and characterized (concentration levels and diversity) at 1 outdoor and 6 indoor sites within a Swiss dairy production facility. Air samples were collected on 2 sampling dates in different seasons, one in February and one in July 2012 using impaction bioaerosol samplers. After cultivation, isolates were identified by mass spectrometry (matrix-assisted laser desorption/ionization-time-of-flight) and molecular (sequencing of 16S rRNA and rpoB genes) methods. In general, total airborne particle loads and total bacterial counts were higher in winter than in summer, but remained constant within each indoor sampling site at both sampling times (February and July). Bacterial numbers were generally very low (<100 cfu/m3 of air) during the different steps of milk powder production. Elevated bacterial concentrations (with mean values of 391 ± 142 and 179 ± 33 cfu/m3 of air during winter and summer sampling, respectively; n = 15) occurred mainly in the “logistics area,” where products in closed tins are packed in secondary packaging material and prepared for shipping. However, total bacterial counts at the outdoor site varied, with a 5- to 6-fold higher concentration observed in winter compared with summer. Twenty-five gram-positive and gram-negative genera were identified as part of the airborne microflora, with Bacillus and Staphylococcus being the most frequent genera identified. Overall, the culturable microflora community showed a composition typical and representative for the specific location. Bacterial counts were highly correlated with total airborne particles in the size range 1 to 5 µm, indicating that a simple surveillance system based upon counting of airborne particles could be implemented. The data generated in this study could be used to evaluate the effectiveness of the dairy plant’s sanitation program and to identify potential sources of airborne contamination, resulting in increased food safety. 相似文献
14.
Susanne Neugart Hans-Peter Kläring Michaela Zietz Monika Schreiner Sascha Rohn Lothar W. Kroh Angelika Krumbein 《Food chemistry》2012
The winter crop kale has a complex profile of different glycosylated and acylated flavonol glycosides which may be affected by global warming. To the best of our knowledge, compound–climate relationships for flavonol aglycones and flavonol glycosides were established for the first time. The investigated 10 major flavonol glycosides responded structure-dependent in the investigated temperature range between 0 and 12 °C and the photosynthetic active radiation range between 4 and 20 mol m−2 d−1, e.g. the decrease in temperature led to an increase in sinapic acid monoacylated and diacylated quercetin glycosides, while the sinapic acid monoacylated kaempferol glycosides showed a maximum at 4.5 °C. Furthermore, the hydroxycinnamic acid residues and the different number of glucose moieties in the 7-O position affected the response of kaempferol triglucosides. Consequently, global warming would result in lower concentrations of antioxidant-relevant quercetin glycosides in winter crops, suggesting a production at e.g. higher altitudes due to lower temperature. 相似文献
15.
Christian Pahl Eberhard Hartung Anne Grothmann Katrin Mahlkow-Nerge Angelika Haeussermann 《Journal of dairy science》2014
Monitoring rumination behavior serves multiple purposes in feeding and herd management of dairy cows. The process of calving is a major event for cows, and a detailed understanding of alterations in behavioral patterns of animals in the time around calving is important in calving detection. The objective of this study was to describe the short-term changes in rumination patterns in dairy cows immediately before and after parturition. In total, 17 cows were fitted with rumination sensors that were able to monitor rumination time, number of rumination boli, and number of rumination jaw movements. Rumination time was decreased in the last 4 h antepartum and in the first 8 h postpartum. Cows stopped ruminating 123 ± 58 min (mean ± standard deviation) before calving and resumed ruminating 355 ± 194 min after calving. The number of rumination jaw movements and boli per day were decreased in the 24-h period postpartum. Rumination rate, the number of rumination jaw movements per rumination minute, and the number of boli per rumination minute changed little around calving. The calving event primarily influenced the duration and frequency of various rumination characteristics but not rumination intensity. Among detected characteristics, rumination time showed the greatest potential for monitoring of calving events. 相似文献
16.
Fire retardants may considerably improve the fire properties of wood products, but the durability, e.g. in exterior applications, has not been addressed fully. This paper reviews the existing knowledge and experience mainly from the USA with the aim of supporting further development in Europe. The review is concentrated on pressure impregnated fire retardant treated wood products which have the best opportunities for increased durability. Copyright © 2001 by John Wiley & Sons, Ltd. 相似文献
17.
Malgorzata Wachowska Alicja Wojciechowska Angelika Muchowicz 《International journal of molecular sciences》2022,23(1)
Tumor-associated neutrophils appear to be a crucial element of the tumor microenvironment that actively participates in the development and progression of cancerous diseases. The increased lifespan, plasticity in changing of phenotype, and functions of neutrophils influence the course of the disease and may significantly affect survival. In patients with chronic lymphocytic leukemia (CLL), disturbances in neutrophils functions impede the effective immune defense against pathogens. Therefore, understanding the mechanism underlying such a phenomenon in CLL seems to be of great importance. Here we discuss the recent reports analyzing the phenotype and functions of neutrophils in CLL, the most common leukemia in adults. We summarize the data concerning both the phenotype and the mechanisms by which neutrophils directly support the proliferation and survival of malignant B cells. 相似文献
18.
In this study, the gel strength and visible microstructure of fat containing β-lactoglobulin-κ-carrageenan gels were investigated using puncture testing and confocal scanning laser microscopy, respectively. The gel strength was closely linked to the visible microstructure of the whey protein network as stained with Rhodamine B. Covalent labelling of κ-carrageenan with FITC prior to gel formation enabled localisation of the hydrocolloid phase, but caused a significant drop in the gel strength. This effect coincided with the observed reduction of the κ-carrageenan intrinsic viscosity, which was found to be a result of the labelling process. The use of a novel dye, V03-01136, for the staining of fat allowed for the specific and concurrent visualisation of the protein, hydrocolloid and fat phases under the conditions applied in the study. 相似文献
19.
Østlie HM Eliassen L Florvaag A Skeie S 《International journal of food microbiology》2004,94(3):287-299
Microbiological sampling of Norvegia cheese from three cheese factories was done during ripening. The evolution of aerobic mesophilic bacteria, lactococci, lactobacilli, enterococci, presumptive leuconostoc and pediococci was investigated after 30, 90, 180 and 270 days of ripening. Isolates (135) of non-starter lactic acid bacteria (NSLAB) from nine Norvegia cheeses after 90, 180 and 270 days of ripening were examined. The isolates were tested by physiological and biochemical assays, species-specific PCR and 16S rDNA sequencing. After 90 days of ripening Leuconostoc spp., most probably from the starter, and the NSLAB specie Lactobacillus paracasei dominated among the isolates, however, after longer ripening Lb. paracasei dominated. The development and evolution of the microflora in Norvegia varied according to dairy and ripening time. 相似文献
20.
Methods for determining pesticides and polychlorinated biphenyls in food samples--problems and challenges 总被引:2,自引:0,他引:2
Determination of residual amounts of pesticides and polychlorinated biphenyls (PCBs) in food samples requires the use of specific techniques regarding sample preparation as well as instrumental analysis which should be characterized by a very low detection limit. A problem associated with the use of pesticides and PCBs is the need for controlling their residues in the environment, particularly in food, as these chemicals show a propensity to accumulate. The analysis of food samples for the presence of pesticides and PCBs brings on many difficulties because of the specificity of sample preparation consisting of multistep purification procedures of samples that contain trace amounts of an analyte. Concentration determinations of pollutants that easily dissolve in complex matrices, particularly in the presence of a large apportionment of interfering substances, pose a big challenge. Therefore, the basic step in food analysis for the presence of pesticides and PCBs is sample preparation which mainly consists of analyte enrichment and the removal of interfering substances. But all steps of the analytical procedure that include sample collection and preparation, extraction of analytes from matrix, extract purification, and final determination, are very significant; their precision and correct application have a decisive effect on the final result. 相似文献