High herd-level prevalence of Mycobacterium avium subspecies paratuberculosis in Western Canadian dairy farms,based on environmental sampling

Mycobacterium avium subspecies paratuberculosis (MAP) causes chronic progressive enteritis in ruminants. The pathogen is present in most countries with modern dairy production, causing substantial economic losses for the industry. The objectives of this study were to estimate dairy herd prevalence of MAP in the Western Canadian provinces of Alberta and Saskatchewan, and to determine whether herd size and housing system (tie-stall versus freestall or loose housing) affected the risk of a herd testing positive for MAP. Six environmental samples were collected on 360 Alberta farms (60% of registered producers) and on 166 Saskatchewan dairy farms (99%). In total, 47% of the sampled farms in Alberta and 53% of the sampled farms in Saskatchewan had at least one environmental sample that was MAP culture positive and were, therefore, defined as infected. Sensitivity of environmental sampling was estimated using 3 subsequent annual tests performed on 82 farms. Because laboratory protocols were continuously improved throughout the project, the sensitivity increased over time. Therefore, a mean of the sensitivity estimates weighted on sampling year was constructed; this resulted in sensitivities of 68 and 69% for Alberta and Saskatchewan, respectively. Implementing those estimates in an approximate Bayesian computation model resulted in a true herd prevalence of 68% (95% probability interval: 60–80%) for Alberta and 76% (95% probability interval: 70–85%) for Saskatchewan. Herds with >200 cows had 3.54 times higher odds of being environmental sample positive and had more positive samples than herds with <50 cows (neither province nor housing system affected those results). In conclusion, the majority of Alberta and Saskatchewan dairy farms were infected with MAP and larger herds were more often MAP positive than smaller herds.     

Impact of particle size distribution on rheological and textural properties of chocolate models with reduced fat content

ABSTRACT:  With an increasing consumption of lipids nowadays, decreasing the fat content in food products has become a trend. Chocolate is a fat-based suspension that contains about 30%wt fat. Reducing fat content causes an increase in the molten chocolate viscosity. This leads to 2 major issues: difficulties in the process and a loss of eating quality in the final product, reported to have poor in-mouth melting properties, remain hard, and difficult to swallow. Literature shows that optimizing the particle size distribution (PSD), that is, having one with an increased packing fraction, can decrease the viscosity of highly concentrated suspensions. This study focuses on the impact of the PSD and fat content on the rheological properties, melting behavior, and hardness of chocolate models (dispersions of sugar in fat). We show that optimizing the PSD while reducing the fat content to a critical amount (22%wt) can decrease the viscosity of the molten material and reduce the hardness of the crystallized chocolate models. Melting in the mouth, characterized by an in vitro collapse speed, is faster for the samples with an optimized PSD. The decrease in the viscosity by optimizing the PSD in systems with a constant fraction of medium phase is based on the decrease of interparticle contact, reducing the particle aggregates strength, and structure buildup during flow or meltdown. In its crystallized state, the particle network is less interconnected, providing less resistance to breakage and meltdown.     

In situ observation of CO2 sequestration reactions using a novel microreaction system

A novel, externally controlled microreaction system has been developed to provide the first in situ observations of the reaction processes that control CO2 sequestration via mineral carbonation. The system offers pressure (to 20 MPa), temperature (to 250 degrees C), and activity control suitable for investigating a variety of fluid-fluid and fluid-solid interactions of environmental interest. Mineral sequestration efforts to date have effectively accelerated carbonation, a natural mineral weathering process, to an industrial timescale. However, the associated reaction mechanisms are poorly understood, limiting further process development. Synchrotron X-ray diffraction and Raman spectroscopy have been used to provide the first in situ insight into the associated supercritical mineral carbonation process. Magnesite was found to form directly under the reaction conditions observed (e.g., 150 degrees C and 15 MPa CO2),facilitating geologically stable sequestration. Thermodynamic analysis of fluid-phase species concentrations in the Na+ buffered H2O-CO2 reaction system found the primary aqueous reactant species to be CO2(aq) and HCO3-, with CO2(aq) more prevalent under the reaction conditions observed. The microreactor provides a powerful new tool for in situ investigation of a broad range of environmentally, fundamentally, and commercially important processes, including the reactions associated with geological carbon dioxide sequestration.     

更健壮的印刷业

drupa 2004将成为“彩色印刷的drupa”。彩色印刷及其自动化的发展在传统的胶印、凹印和柔印工艺中成为关注的焦点。在数字式印刷中，彩色激光和喷墨系统展现了各种不同的应用，表明印刷行业正越来越健壮地发展。参观drupa 2004的人因此会了解到合理的生产方式和创新产品的致富之路。     

Peanut varieties with reduced Ara h 1 content indicating no reduced allergenicity

Peanut allergy is a major cause of food‐induced severe anaphylactic reactions. To date, no medical care is available to prevent and treat peanut allergy and therefore hypoallergenic peanut varieties are of considerable health political and economic interest. Major allergens that induce IgE‐responses in peanut‐sensitive patients are Ara h 1, Ara h 2 and Ara h 3/4. In order to identify hypoallergenic peanuts, commercially locally available peanut varieties were screened for their allergen content. Ara h 1‐deficient peanuts from Southeast Asia were identified by SDS‐PAGE, immunoblotting, inhibition assays and ELISA. 2‐D PAGE analyses demonstrated the different compositions of the tested extracts and revealed a number of variations of the allergen patterns of peanuts from different varieties. Mediator release experiments of these peanut extracts demonstrated similar allergenicities as compared with standard peanut extract. These results indicate that the allergenicity of peanuts with reduced Ara h 1 content might be compensated by the other allergens, and thus do not necessarily cause a reduction of allergenicity.     

Factors influencing falling number in winter wheat

The Hagberg falling number (HFN) is one of the most important quality characteristics of wheat. Six winter wheat cultivars from three locations in Germany were analysed to assess the factors influencing the HFN. The cultivars and locations affected significantly the HFN of all the samples. The infection with Fusarium culmorum, determined in another cultivar, also led to an increase in HFN, which suggested that the HFN method is not adequate enough for the true determination of the alpha-amylase activity of fungus-infected, wheat flour. Furthermore, there was no clear correlation between HFN and thousand-kernel weight, starch content or pentosan content. The crude protein content was positively related to the HFN, while the total dietary fibre content depended on the cultivar and location.     

Genetic parameters for cheese-making properties and milk composition predicted from mid-infrared spectra in a large data set of Montbéliarde cows

Cheese-making properties of pressed cooked cheeses (PCC) and soft cheeses (SC) were predicted from mid-infrared (MIR) spectra. The traits that were best predicted by MIR spectra (as determined by comparison with reference measurements) were 3 measures of laboratory cheese yield, 5 coagulation traits, and 1 acidification trait for PCC (initial pH; pH_0PPC). Coefficients of determination of these traits ranged between 0.54 and 0.89. These 9 traits as well as milk composition traits (fatty acid, protein, mineral, lactose, and citrate content) were then predicted from 1,100,238 MIR spectra from 126,873 primiparous Montbéliarde cows. Using this data set, we estimated the corresponding genetic parameters of these traits by REML procedures. A univariate or bivariate repeatability animal model was used that included the fixed effects of herd × test day × spectrometer, stage of lactation, and year × month of calving as well as the random additive genetic, permanent environmental, and residual effects. Heritability estimates varied between 0.37 and 0.48 for the 9 cheese-making property traits analyzed. Coagulation traits were the ones with the highest heritability (0.42 to 0.48), whereas cheese yields and pH_{0 PPC} had the lowest heritability (0.37 to 0.39). Strong favorable genetic correlations, with absolute values between 0.64 and 0.97, were found between different measures of cheese yield, between coagulation traits, between cheese yields and coagulation traits, and between coagulation traits measured for PCC and SC. In contrast, the genetic correlations between milk pH_{0 PPC} and CY or coagulation traits were weak (?0.08 to 0.09). The genetic relationships between cheese-making property traits and milk composition were moderate to high. In particular, high levels of proteins, fatty acids, Ca, P, and Mg in milk were associated with better cheese yields and improved coagulation. Proteins in milk were strongly genetically correlated with coagulation traits and, to a lesser extent, with cheese yields, whereas fatty acids in milk were more genetically correlated with cheese yields than with coagulation traits. This study, carried out on a large scale in Montbéliarde cows, shows that MIR predictions of cheese yields and milk coagulation properties are sufficiently accurate to be used for genetic analyses. Cheese-making traits, as predicted from MIR spectra, are moderately heritable and could be integrated into breeding objectives without additional phenotyping cost, thus creating an opportunity for efficient improvement via selection.     

Heme-dependent and heme-independent nitrite reduction by lactic acid bacteria results in different N-containing products

Seventy strains of lactic acid bacteria were investigated for nitrite reductase activity. Two types of this activity were detected. Type I was found in Lactobacillus plantarum, L. pentosus and Pediococcus pentosaceus. This activity is heme-dependent with ammonia as the sole product. Type II mechanism is heme-independent and reduces nitrite to NO and N₂O.     

Structural characteristics of cocoa particles and their effect on the viscosity of reduced fat chocolate

Aimed at the manufacture of reduced fat chocolates, a novel method of trapped fat reduction was assessed: Manipulation of the cocoa ingredient. Cocoa mass was replaced with cocoa powder (11 g/100 g or <1 g/100 g fat) and added ‘free’ cocoa butter. A cocoa solids approach to design reduced fat chocolates with satisfactory flow properties is attractive to industry since it circumvents introduction of ingredients not commonly used in chocolate manufacture. Results showed that the cocoa mass chocolate had a higher viscosity than cocoa powder chocolates of the same total fat content due to the presence of trapped fat globules as identified by confocal laser scanning microscopy. The chocolate prepared with standard defatted cocoa powder containing 11 g/100 g fat had a lower viscosity than the chocolate containing highly defatted cocoa powder (<1 g/100 g) due to particle shape and fat diffusion into the particles as revealed by microscopy analyses. Based on the evidence presented, it can be concluded that standard defatted cocoa powder, as widely used by the industry, is indeed the best compromise in terms of free fat, particle size and morphology attempting to formulate fat reduced chocolate of acceptable molten state viscosity.     

Weiterentwicklung des Ring-Kern-Verfahrens zur Messung von Eigenspannungen

Anwendung des Ring-Kern-Verfahrens zur Messung von Eigenspannungen in den Randschichten schwerer Schmiedestücke. Ableitung der Grundgleichungen für den Zusammenhang zwischen gemessenen Dehnungsänderungen und den zu ermittelnden Eigenspannungen bei gleichmäßiger und ungleichmäßiger Spannungsverteilung im Inneren. Näherungsverfahren und Vereinfachungen. Grenzwertbetrachtungen. Verbesserte Arbeitsweise bei der Durchführung der Messungen. Herstellung der Ringnut mit einem besonders gestalteten Kronenfräser. Ermittlung der Abklingfunktionen in Eichversuchen. Vereinfachte Auswertung mit Nomogrammen.