Biodiversity and safety aspects of yeast strains characterized from vineyards and spontaneous fermentations in the Apulia Region,Italy

This work is the first large-scale study on vineyard-associated yeast strains from Apulia (Southern Italy). Yeasts were identified by Internal Transcribed Spacer (ITS) ribotyping and bioinformatic analysis. The polymorphism of interdelta elements was used to differentiate Saccharomyces cerevisiae strains. Twenty different species belonging to 9 genera were identified. Predominant on the grape surface were Metschnikowia pulcherrima, Hanseniaspora uvarum and Aureobasidium pullulans, whereas M. pulcherrima and H. uvarum were dominant in the early fermentation stage. A total of 692 S. cerevisiae isolates were identified and a number of S. cerevisiae strains, ranging from 26 to 55, was detected in each of the eight fermentations. The strains were tested for biogenic amines (BAs) production, either in synthetic media or grape must. Two Pichia manshurica, an Issatchenkia terricola and a M. pulcherrima strains were able to produce histamine and cadaverine, during must fermentation. The production of BAs in wine must was different than that observed in the synthetic medium. This feature indicate the importance of an “in grape must” assessment of BAs producing yeast. Overall, our results suggest the importance of microbiological control during wine-making to reduce the potential health risk for consumer represented by these spoilage yeasts.     

The breakdown properties of heat-set whey protein emulsion gels in the human mouth

Differently structured whey protein emulsion gels were formed by heating at different concentrations of NaCl. The formation of gels was monitored by oscillatory rheometry. The large deformation properties relevant to breakdown properties in the human mouth were measured by a uniaxial compression test and fracture wedge set test using a texture analyzer. A panel of 8 subjects was used to examine the in-mouth behaviours of gels including mastication parameters, degree of fragmentation and oil droplet release. The results showed that in general the gel hardness increased with increasing NaCl concentration. The gels containing 10/25 and 100/200 mM NaCl were characterized as being soft and hard, respectively. These soft and hard gels had different breakdown patterns in the mouth. On the other hand, sensory experiments showed the gel with 10 mM NaCl needed a significantly lower number of chewing cycles (19.4 ± 2.1) compared with gels with higher NaCl. The values of median size of particles in masticated gels containing 10, 25, 100 and 200 mM NaCl were about 4.00, 2.85, 1.05 and 0.95 mm, respectively, which suggested that higher hardness led to greater fragmentation in the human mouth. The fragmentation of the gel was highly correlated with functions of the mechanical properties. There was no obvious coalescence of the oil droplets during oral processing and only very few oil droplets were released from protein matrix during mastication.     

Phytochemical Composition and Anti-Inflammatory Activity of Extracts from the Whole-Meal Flour of Italian Durum Wheat Cultivars

In this study, the quali-quantitative composition of hydrophilic (phenolic acids) and lipophilic (isoprenoids) extracts from whole-meal flour of five elite Italian durum wheat cultivars was determined. Significant differences in the content of bioactive compounds were observed among the wheat extracts, in particular concerning the content of bound phenolic acids, lutein and β-tocotrienols. The cultivars Duilio and Svevo showed the highest amount of phenolic acids and isoprenoids, respectively. Extracts were evaluated for their anti-inflammatory activity on HT-29 human colon cells by measuring the levels of interleukin 8 (IL-8) and transforming growth factor β1 (TGF-β1). Durum wheat extracts significantly inhibited the secretion of the pro-inflammatory IL-8 mediator at 66 µg/mL of phenolic acids and at 0.2 µg/mL of isoprenoids. Conversely, the secretion of the anti-inflammatory mediator TGF-β1 was not modified by neither hydrophilic nor lipophilic extracts. These results provide further insight into the potential of durum wheat on human health suggesting the significance of varieties with elevated contents of bioactive components.     

Nuclear shielding of openings in ITER Tokamak building

The external walls of the Tokamak building, made of thick concrete, provide the nuclear shielding for operators working in adjacent buildings and for the environment. There are a series of openings to these external walls, devoted to ducts or pipes for ventilation, waveguides and transmission lines for heating systems and diagnostics, cooling pipes, cable trays or busbars. The shielding properties of the wall shall be preserved by adequate design of the openings in order not to affect the radiological zoning in adjacent areas. For some of them, shielding properties of the wall are not affected because the size of the network is quite small or the source is far from the opening. But for most of the openings, specific features shall be considered. Even if the approach is the same and the ways to shield can be standardized, specific analysis is requested in any case because the constraints are different.     

Proficiency Testing in Chemical Analysis of Iron Ore: Comparison of Statistical Methods for Outlier Rejection

Participation in proficiency testing (PT) is an important task to meet the requirements of ISO/IEC 17025 in the area of quality assurance of laboratory results. A PT program in the field of chemical analysis of iron ore was organized by CSIR-National Metallurgical Laboratory, Jamshedpur (nodal laboratory) and CSIR-National Physical Laboratory, New Delhi (PT Coordinator) during November 2011–January 2012. Twenty-two (22) laboratories in India participated in the PT program. The results of participating laboratories were first analyzed to identify the distribution patterns and the presence of outliers. Several parametric and robust statistical methods were used to identify the outliers. Correct outlier rejection is of utmost importance because the choice of the outlier test method influence the consensus value and standard deviation which in turn determine the Z-score of a laboratory result in a PT program. In the present study, five parametric outlier tests were compared: Dixon’s Q test, Grubbs single test, double test, t test, and Z-scores. In addition three robust tests as alternative to parametric tests were chosen: box plot, Huber test and MAD-based test. It was observed that multiple outlier test methods should be used to identify the outliers in a PT program especially when the number of participating laboratories is less. They complement each other and helps give diverse information and better overview of the data set. Among the 22 participating laboratories, Z-scores of 4 laboratories for analysis of total iron fall outside the acceptable limit of ±2. Similarly, for analysis of alumina and silica, five laboratories had unacceptable Z-scores.