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This paper describes the development and application of a novel method for the analysis of phthalates in wine using HPLC-MS/MS combined with a hold-back column. Phthalates are ubiquitous contaminants in the environment and can be widely found in laboratory materials and equipment. A HPLC system is no exception and can be the source of contamination affecting the accuracy and precision of analytical results. The new method successfully separates phthalates from the different sources, a wine sample and HPLC system by a simple technique using an additional HPLC column (a hold-back column) placed upstream of the injection valve. The hold-back column effectively retains the HPLC-derived contaminants during column equilibrium time and delays their elution times from an analytical column. Consequently, a phthalate from a wine sample can be baseline separated as it elutes sufficiently earlier than the same phthalate from the HPLC system. HPLC-MS/MS analysis combined with the hold-back column demonstrated virtually no influence of the HPLC contaminants on the quantification of phthalates present in wine. Together with a simple and rapid sample preparation and the use of labeled internal standards, the method was confirmed to be robust and reliable to determine concentrations of phthalates in wine. Quantification limits were within the range of 1.6-9.8 μg L-1 for dimethyl, diethyl, dibutyl, benzylbutyl, bis(2-ethylhexyl) and dioctyl phthalates, and 7.5-26.6 μgL-1 for multiple isomeric phthalates, di-iso-nonyl and di-iso-dodecyl phthalates. © 2014 Elsevier B.V. Source

Borneman A.R.,The Australian Wine Research Institute | Pretorius I.S.,Macquarie University
Genetics | Year: 2015

The Saccharomyces sensu stricto group encompasses species ranging from the industrially ubiquitous yeast Saccharomyces cerevisiae to those that are confined to geographically limited environmental niches. The wealth of genomic data that are now available for the Saccharomyces genus is providing unprecedented insights into the genomic processes that can drive speciation and evolution, both in the natural environment and in response to human-driven selective forces during the historical “domestication” of these yeasts for baking, brewing, and winemaking. © 2015, by the Genetics Society of America. All rights reserved. Source

Curtin C.D.,The Australian Wine Research Institute | Pretorius I.S.,Macquarie University
FEMS Yeast Research | Year: 2014

Brettanomyces bruxellensis, like its wine yeast counterpart Saccharomyces cerevisiae, is intrinsically linked with industrial fermentations. In wine, B. bruxellensis is generally considered to contribute negative influences on wine quality, whereas for some styles of beer, it is an essential contributor. More recently, it has shown some potential for bioethanol production. Our relatively poor understanding of B. bruxellensis biology, at least when compared with S. cerevisiae, is partly due to a lack of laboratory tools. As it is a nonmodel organism, efforts to develop methods for sporulation and transformation have been sporadic and largely unsuccessful. Recent genome sequencing efforts are now providing B. bruxellensis researchers unprecedented access to gene catalogues, the possibility of performing transcriptomic studies and new insights into evolutionary drivers. This review summarises these findings, emphasises the rich data sets already available yet largely unexplored and looks over the horizon at what might be learnt soon through comprehensive population genomics of B. bruxellensis and related species. © 2014 Federation of European Microbiological Societies. Source

Cozzolino D.,The Australian Wine Research Institute
Combinatorial Chemistry and High Throughput Screening | Year: 2011

Chemical and physiological properties are related to individual or bioactive compounds such as essential oils terpenoids flavonoids volatile compounds and other chemicals which are present in natural products in low concentrations (e.g. ppm or ppb). For many years classical separation chromatographic and spectrometric techniques such as high performance liquid chromatography (HPLC) gas chromatography (GC) liquid chromatography (LC) and mass spectrometry (MS) have been used for the elucidation of isolated compounds from different matrices. Hence the use of standard separation chromatographic and spectrometric methods was found useful in chemical and both plant and animal physiology studies for fingerprinting and comparing natural and synthetic samples as well as to identify single active compounds. It has been generally accepted that a single analytical technique will not provide sufficient visualization of the metabolome hence holistic techniques are needed for comprehensive analysis. In the last 40 years near infrared (NIR) spectroscopy became one of the most attractive and used methods of analyzing agricultural related products and plant materials which provide simultaneous rapid and non-destructive quantitation of major. This technique has been reported to determine other minor compounds in plant materials such as volatile compounds and elements. The aim of this short review is to describe some recent applications of NIR spectroscopy combined with multivariate data analysis for high throughput screening of metabolites with an emphasis on food and medical applications. ©2011 Bentham Science Publishers Ltd. Source

Cozzolino D.,The Australian Wine Research Institute
Analytical and bioanalytical chemistry | Year: 2011

Information about constituents of grape juice, must, and wine can be used for management and decision support systems in order to improve, monitor, and adapt grape and wine production to new challenges. Numerous sensors that gather this information are either currently available or in development. Nevertheless there is still a need to adapt these sensors to special requirements, for example robustness, calibration and maintenance, operating costs, duration, sensitivity, and specificity to a particular application. The sensors commonly used by the wine industry are those that are based on mid-infrared (MIR), near-infrared (NIR), visible (VIS) and ultraviolet (UV) spectroscopy. This article reviews some recent technical solutions for analysis of juice, must and wine based on the combination of infrared spectroscopy and chemometrics. Source

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