Analysis of triclosan and 4n‐nonylphenol in Colombian reservoir water by gas chromatography‐mass spectrometry

In this work were determined triclosan and 4n‐nonylphenol in water from a reservoir that is used to provide water to a purification plant in an important city in Colombia. The analytical methodology was validated using solid‐phase extraction and analysis by gas chromatography‐mass spectrometry (GC‐MS). The analysis by GC‐MS showed good linearity in the range of 0.05–5 μg/L for both compounds. Recoveries from 79 to 109% and standard deviations of 2.5–7.7 for low concentrations and from 3.8 to 9.6 (n = 5) for high concentrations were obtained for both compounds. In Colombia, this is the first time that these compounds have been analysed in water supplying of a drinking water treatment plant. The validated method was applied to the analysis of 27 samples collected in August 2010 in 11 locations from the reservoir and in the influent and effluent of the drinking water treatment plant. In total, seven samples were found to contain triclosan.     

Detailed modeling of the video signal and optimal readout of charge-coupled devices

This article provides a practical design methodology to calculate an optimal filter for noise reduction in the readout of charge-coupled devices (CCDs) taking into account the charge transfer and feedthroughs due to capacitive coupling in the CCD. A detailed analysis of the dynamics of the video signal and charge transfer is presented, including the circuital modeling of the output stage of the CCD and the dynamics of the electronics in the video chain before the analog-to-digital (AD) converter. This model is used to compute an optimal filter that minimizes the variance of the pixel noise and uses the samples of the charge transfer, before the charge is fully settled. This is necessary to enhance the performance of previous results that also use optimal filters but do not use the transition samples, while also reducing the pixel readout time, resulting in faster readouts. As a proof of concept for the optimal filter, we present novel experimental results using a Skipper CCD, which has a floating sense node that allows to measure the charge packet an arbitrary number of times. However, this technique can be applied to any CCD that has a readout system that digitally samples the video signal.     

Effect of native and acetylated‐crosslinked waxy corn starch‐beeswax coatings on quality attributes of raspberries during storage

Edible coatings (ECs) are a thin layer of a mixture of edible materials, applied in the liquid state and dried over the surface of a food product to maintain its quality during storage. This work was aimed to study the effect of ECs made from wx corn starch (WCS) or acetylated cross‐linked starch (ACLS) added with beeswax on fresh raspberry quality attributes during short‐term cold storage. Freshly harvested fruits were coated, dried, packed in plastic trays and stored up to 8 days at 4°C. During storage quality parameters such as firmness, respiration rate, anthocyanins content, total phenols, color changes, and weight loss were evaluated. A clear effect on control of respiration rate was observed in coated raspberries. Respiration rate of uncoated fruit was 4.5 ± 0.28 mmol/kg/h and decreased to 4.2 ± 0.27 for ACLS and to 4.1 ± 0.08 mmol/kg/h for WCS‐coated raspberries, after 56 h of storage at 15°C. Ethylene production followed a similar trend under these conditions decreasing from 0.043 ± 0.005 to 0.034 ± 0.004 mmol/kg/h for uncoated and ACLS coated fruits, respectively, indicating an effect on ripening control. Additionally, ACLS and WCS coatings permitted the preservation of color without affecting anthocyanins content. However, the presence of anaerobic metabolites and reduction of terpenes production in cold stored coated raspberries indicated hypoxic conditions, which can adversely affect shelf‐life quality attributes of raspberries such as firmness and weight loss.     

Comparison of Oxidation Stability and Quenchant Cooling Curve Performance of Soybean Oil and Palm Oil

The potential use of vegetable oil-derived industrial oils continues to be of great interest because vegetable oils are relatively non-toxic, biodegradable, and they are a renewable basestock alternative to petroleum oil. However, the fatty ester components containing conjugated double bonds of the triglyceride structure of vegetable oils typically produce considerably poorer thermal-oxidative stability than that achievable with petroleum basestocks under typical use conditions. Typically, these conditions involve furnace loads of hot steel (850 °C), which are rapidly immersed and cooled to bath temperatures of approximately 50-60 °C. This is especially true when a vegetable oil is held in an open tank with agitation and exposed to air at elevated temperatures for extended periods of time (months or years). This paper will describe the thermal-oxidative stability and quenching performance of soybean oil and palm oil and the resulting impact on the heat transfer coefficient. These results are compared to typical fully formulated, commercially available accelerated (fast) and an unaccelerated (slow) petroleum oil-based quenchants.     

Study of supply-chain management in the automotive industry: a bibliometric analysis

The economic and social importance of the?automotive industry explains the need for researching improved ways of?organising and?managing the diverse processes involved in the production of?motor vehicles. Furthermore, the management of supply chains and inter-organisational?relations has acquired strategic significance in recent years and has become a?key area of research. At the interface?between these two fields, this paper adopts a bibliometric viewpoint to analyse the scholarly literature that has addressed?the study of?supply chains within the specific sphere of the automotive?industry. To do so, it has examined the 404 papers on this topic indexed?through to 2011 in the Business Source Complete database. This has allowed?identifying trends and opportunities related to the what, how and where of research into this matter.     

Direct characterization of commercial lecithins by easy ambient sonic-spray ionization mass spectrometry

Commercial lecithins are composed mainly of phospholipids and triacylglycerols. The analysis of the commercial lecithins, including their fraction of phospholipids, normally involves laborious and expensive protocols. Easy ambient sonic-spray ionization mass spectrometry (EASI-MS) is shown to be an efficient technique for the analysis of lipids. Samples of commercial lecithins including standards, refined, deoiled and modified soy lecithin were tested. Characteristic profiles of phosphatidylcholines and triacylglycerols are detected by EASI(+)-MS, whereas EASI(-)-MS provided phosphatidylethanolamines, glycophospholipids and free fatty acids profiles. Acetylated lecithins also displayed characteristic acetylated derivatives. EASI-MS data was also compared to MALDI-MS, and found to display richer compositional information. The industrial process applied to lecithin fabrication was also characterised via typical EASI-MS profiles. EASI-MS both in its positive and negative ion modes offers a direct, fast and efficient technique able to characterise commercial lecithin.     

Mineral profile of “fino” wines using inductively coupled plasma optical emission spectrometry methods

Fifty wines from the Denomination of origin (DO) of Condado de Huelva were analysed for mineral content by measuring 12 elements (Al, Ba, Ca, Cu, Fe, K, Mg, Mn, Na, P, Sr and Zn) using Inductively Coupled Plasma-Optical Emission Spectrometry (ICP-OES). Samples were previously digested by heating with H₂O₂/HNO₃ mixture. The results obtained showed that metal data set were non-normally distributed and accordingly, non-parametric statistics were applied. The average levels (medians) of these elements found in the samples are as follows, in mg/L: 2.54 (Al); 0.06 (Ba); 82.58 (Ca); 0.21 (Cu); 3.53 (Fe); 865.34 (K); 68.87 (Mg); 0.71 (Mn); 32.77 (Na); 71.61 (P); 0.48 (Sr); 0.56 (Zn). The interrelation of metal couples was studied through the Spearman non-parametric sample correlation, being Fe/Al, P/Mg, and Zn/Ba the most important correlations established. As a result of this study, we can suggest that the contribution to the safety intake limits (per week) of the studied elements through the wine consumption is not significant. Actually, they range between 0.1% in Fe and 11.9% in Mg, for normal drinkers.     

Longitudinal Dissemination of Salmonella enterica Clonal Groups through the Slaughter Process of Salmonella-Positive Pig Batches

This study was conducted to assess the dissemination of Salmonella clonal groups in slaughterhouses that received batches of Salmonella -positive pigs and used different routine processing procedures. Eight serial sampling sessions were conducted in three slaughterhouses (A, B, and C). Blood was collected randomly (n = 25) from each batch of pigs and processed for serology. Carcasses (n = 12) were identified and sampled after dehairing, after singeing, after evisceration, and before chilling. A section of cecum also was collected. Salmonella isolates were submitted to pulsed-field gel electrophoresis. The overall seroprevalence of Salmonella was 80.6% (316 of 392 samples), and cecal contents were positive for Salmonella in 23.8% (26 of 109) of the pigs sampled. Carcasses after dehairing had a significantly higher prevalence of Salmonella (P = 0.004) and the highest Salmonella levels (median ～ 0.26 log CFU/300 cm(2)). The singeing step significantly affected the Salmonella status of the carcasses (P = 0.001); however, the efficacy of singeing differed among slaughterhouses. In the prechilling step, 14.7% (16 of 109) of the carcasses were positive for Salmonella. Salmonella pulsotypes found on the prechill carcasses were also found in the lairage, in the cecal contents, and on carcasses after dehairing, suggesting that the main source of contamination was the slaughter process before singeing. Slaughterhouse C was the most likely (odds ration [OR] ～ 6.51) to have pigs carrying Salmonella in the gut, and slaughterhouse B was the most likely (OR ～ 14.66) to have contaminated carcasses at the prechilling step. These findings indicate that the procedures adopted in slaughterhouse B contributed to the spread of Salmonella strains. In contrast, in slaughterhouse C the Salmonella strains carried by the pigs or found in the lairage were not recovered from prechilled carcasses, validating the effectiveness of the slaughterhouse interventions. These results indicate that an effective slaughter process can help decrease the number of Salmonella-positive carcasses in slaughterhouses that receive Salmonella-positive pig batches.     

Short communication: Production of antihypertensive peptide HLPLP by enzymatic hydrolysis: optimization by response surface methodology

This study evaluates the potential ability of proteolytic enzymes to release the antihypertensive peptide HLPLP, β-casein f(134–138), from caseinate. Corolase PP (Röhm GmbH &; Co. KG, Darmstadt, Germany) was found as the most appropriate enzyme to produce this peptide. The optimization of the main experimental variables involved in the process [concentration of Corolase PP, concentration of Peptidase 433P (Biocatalysts Ltd., Parc Nantgarw, UK), and the hydrolysis time on the HLPLP concentration, expressed as area of peak] were studied using a central composite face design. The optimum conditions to obtain the maximum concentration of HLPLP provided by the statistical program were a concentration of Corolase PP of 60 mg/g of protein and hydrolysis time of 24 h. The use of the Peptidase 433P did not increase the amount of the active peptide. The obtained hydrolysate might be used as functional ingredient with antihypertensive properties.