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Ultra-high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (MS) and an alternative technology represented by direct analysis in real time coupled with quadrupole time-of-flight MS were investigated for metabolic fingerprinting of 343 red and white wine samples. Direct injection of pure wine and an extraction procedure optimized for isolation of polyphenols were used to compare different analytical and data handling strategies. After data processing and data pretreatment, principal component analysis was initially used to explore the data structure. Initially, the unsupervised models revealed a notable clustering according to the grape varieties, and therefore supervised orthogonal partial least squares discriminant analysis models were created and validated for separation of red and white wines according to the grape variety. The validated orthogonal partial least squares discriminant analysis models based on data (ions) recorded in positive ionization mode were able to classify correctly 95 % of samples. In parallel, authentication parameters, such as origin and vintage, were evaluated, and they are discussed. A tentative identification of markers was performed using accurate mass measurement of MS and MS/MS spectra, different software packages and different online libraries. In this way, different flavonol glucosides and polyphenols were identified as wine markers according to the grape varieties.

Tortillas are a traditional staple food in Mesoamerican cuisine, which have also become popular on a global level, e.g., for wraps or as snacks (tortilla chips). Traditional tortilla production includes alkaline cooking (nixtamalization) of maize kernels. This article summarizes the current knowledge on mycotoxin changes during the nixtamalization of maize and tortilla production. Upon nixtamalization, mycotoxins can be affected in different ways. On the one hand, the toxins can be physically removed during steeping and washing. On the other hand, mycotoxins might be degraded, modified, or released/bound in the matrix by high pH and/or high temperature. This also applies to the subsequent baking of tortillas. Many studies have shown reduced mycotoxin levels in alkali-cooked maize and in tortillas. Most of the available data relate to aflatoxins and fumonisins. The reduction (and detoxification) of aflatoxins during nixtamalization might, however, be partially reversed in acidic conditions. The loss of fumonisin concentrations is to some extent accompanied by hydrolyzation and by lower toxicity. However, some studies have indicated the potential formation of toxicologically relevant modified forms and matrix-associated fumonisins. More data are required to assess the influence of alkaline cooking regarding such modified forms, as well as mycotoxins other than aflatoxins/fumonisins.

Mycotoxins are naturally present in cereal-based feed materials; however, due to adverse effects on animal health, their presence in derived animal feed should be minimized. A systematic literature search was conducted to obtain an overview of all factors from harvest onwards influencing the presence and concentration of mycotoxins in cereal-based feeds. The feed production processes covered included the harvest time, post-harvest practices (drying, cleaning, storage), and processing (milling, mixing with mycotoxin binders, extrusion cooking, ensiling). Delayed harvest supports the production of multiple mycotoxins. The way feed materials are dried after harvest influences the concentration of mycotoxins therein. Applying fungicides on the feed materials after harvest as well as cleaning and sorting can lower the concentration of mycotoxins. During milling, mycotoxins might be redistributed in cereal feed materials and fractions thereof. It is important to know which parts of the cereals are used for feed production and whether or not mycotoxins predominantly accumulate in these fractions. For feed production, mostly the milling fractions with outer parts of cereals, such as bran and shorts, are used, in which mycotoxins concentrate during processing. Wet-milling of grains can lower the mycotoxin content in these parts of the grain. However, this is typically accompanied by translocation of mycotoxins to the liquid fractions, which might be added to by-products used as feed. Mycotoxin binders can be added during mixing of feed materials. Although binders do not remove mycotoxins from the feed, the mycotoxins become less bioavailable to the animal and, in the case of food-producing animals, to the consumer, lowering the adverse effects of mycotoxins. The effect of extruding cereal feed materials is dependent on several factors, but in principle, mycotoxin contents are decreased after extrusion cooking. The results on ensiling are not uniform; however, most of the data show that mycotoxin production is supported during ensiling when oxygen can enter this process. Overall, the results of the literature review suggest that factors preventing mycotoxin production have greater impact than factors lowering the mycotoxin contents already present in feed materials.

One of the most challenging analytical issues in terms of wine authenticity is the control of geographical origin. This question becomes more and more important in the current context of a global wine market. Single parameters are often not sufficient on their own to determine the product identity with respect to the wine labelling. Recent developments have shown that control is improved by application of multivariate statistical methods to a combination of composition and isotopic data. In the past years, the official European wine control bodies have been confronted with wines that have had to be judged as suspicious in terms of their sophisticated authenticity, falsifications which are not readily identifiable, especially as it regards the grape variety, and particularly highlighted here the geographical origin. To improve the measures of authenticity control, a project with the title “Establishing of a WINE Data Bank for analytical parameters for wines from Third countries (WINE-DB project, G6RD-CT-2001-00646-WINE-DB)” was initiated in 2002, funded by the European Commission within the fifth framework “Competitive and Sustainable Growth”. The project consortium of this multinational project was composed of official and private laboratories from the European Union, from new European member states and a group of university partners for the statistical evaluation. Within the framework of the WINE-DB project, commercial and authentic wines originating from new European member states (Czech Republic, Hungary and Romania) and from overseas countries (South Africa and Australia) are collected and analysed. More than 1,800 wines from three vintages were analysed. First, a sampling plan for each wine-producing country was developed for the authentic samples taking into account, the surface and the grape variety of wine in the respective country. This sampling plan was used for the commercial samples accordingly. A series of three publications was prepared covering the statistical approaches and the results obtained for authentication of wine. The actual one—Part I—provides an overview on the structure of the project, the developing of the sampling plan, the strategy of sample collection and the analytical scheme.

In the context of products from certain regions or countries being banned because of an identified or non-identified hazard, proof of geographical origin is essential with regard to feed and food safety issues. Usually, the product labeling of an affected feed lot shows origin, and the paper documentation shows traceability. Incorrect product labeling is common in embargo situations, however, and alternative analytical strategies for controlling feed authenticity are therefore needed. In this study, distillers’ dried grains and solubles (DDGS) were chosen as the product on which to base a comparison of analytical strategies aimed at identifying the most appropriate one. Various analytical techniques were investigated for their ability to authenticate DDGS, including spectroscopic and spectrometric techniques combined with multivariate data analysis, as well as proven techniques for authenticating food, such as DNA analysis and stable isotope ratio analysis. An external validation procedure (called the system challenge) was used to analyze sample sets blind and to compare analytical techniques. All the techniques were adapted so as to be applicable to the DDGS matrix. They produced positive results in determining the botanical origin of DDGS (corn vs. wheat), and several of them were able to determine the geographical origin of the DDGS in the sample set. The maintenance and extension of the databanks generated in this study through the analysis of new authentic samples from a single location are essential in order to monitor developments and processing that could affect authentication.

The aim of the present study was to compare different spectroscopic techniques using the example of adulteration of pumpkin seed oil with rapeseed oil in combination with a multivariate regression method. A total of 124 pure seed oils and 96 adulterated samples (adulteration levels from 0.5 to 90.0% w/w) were analyzed using mid infrared, Raman, and 1 H-nuclear magnetic resonance spectroscopy. To build quantification models, partial least squares regression (PLS-R) was used. The regression performance parameters, latent variables, and the detection limits (in terms of root mean square error of PLS prediction) calculated when applying the different spectroscopic approaches were compared. For the studied example (pumpkin seed oil adulterated with refined rapeseed oil), the lowest detection limit (3.4% w/w) was obtained for 1 H-nuclear magnetic resonance spectroscopy. For the mid infrared and Raman spectroscopy, detection limits of 4.8% w/w and 9.2% w/w, respectively, were obtained, which might be used as screening methods.

Samples of commercial and authentic [authentic samples are samples produced under microvinification conditions (see Schlesier et al. Eur Food Res Technol, 2009)] wines were collected from four countries (Hungary, Czech Republic, Romania, and South Africa) and three different vintages. They were analyzed for 63 chemical parameters in the context of the European project “Establishing of a wine data bank for analytical parameters from Third Countries”. The aim of the project was to apply multivariate classification techniques to determine the country of origin of wines based on their chemical content. Moreover, it was important to evaluate whether models built for authentic samples can be used to discriminate commercial samples. Here we report on the descriptive and exploratory data analysis and discuss the univariate statistical results. These indicate that South African wines are easily discriminated from the other countries on the basis of a single isotopic ratio such as Ethanol(D/H)₁. The discrimination of the European countries and especially the separation between Hungarian and Czech wines is less straightforward.

More than 50 authentic EU data bank wines from Germany (vintages: 2003, 2004 and 2006) have been extracted by liquid-liquid extraction with a mixture of cyclohexane and 2-methyl-2-propanol. The δ¹³C values of the extracted wine ethanol and other co-extracted higher alcohols have been determined by gas chromatography-combustion-isotope ratio mass spectrometry (GC-C-IRMS). The stable isotope ratios of wine ethanol obtained by liquid-liquid extraction were compared with those obtained after distillation according to the official EU method. No significant differences of the isotope ratios of ethanol measured by the two compared methods were found (R ² = 0.972), thus it was concluded that no significant isotope effect during sample preparation occurred. Additionally, the ¹³C/¹²C isotope ratios of the major co-extracted alcohols, e.g. 2-methylpropan-1-ol, 2- and 3-methylbutan-1-ol, butan-2,3-diol and 2-phenyl-1-ethanol were determined and set in relation to the δ¹³C values of the corresponding extracted wine ethanol. Also, high correlations between their isotope ratios (e.g. 2,3-methylbutan-1-ol R ² = 0.829) were found. The key benefits of the introduced liquid-liquid extraction are the time- and cost-saving determination of δ¹³C values of wine ethanol, the small amount of sample needed for the extraction and additionally the potential analysis of the co-extracted higher alcohols which could be valuable for the detection of fraud.

1 H- and 13 C-NMR-spectra of pistachio oil from Iran, USA and Turkey were analysed with multivariate statistics in order to classify pistachios according to their countries of origin. The integrals of the resonances of the NMR-spectra contain information about the fatty acid composition of pistachio oil which is supposed to reflect the climatic conditions at the crop area. Consequently, NMR-spectroscopy was thought to be a suitable method for the distinction of those pistachio oils. Cluster analysis was found to lead to a distinction between pistachio samples from Turkey and other countries. Principle component analysis was used to extract components from the data, which primarily contain the information about unsaturated acyl chains in the oil and allowed to assign the samples very well to their respective countries of provenance. Linear discriminant analysis provides similar results with low error rate estimations. It was demonstrated that those data gained by 1 H- and 13 C-NMR-spectroscopy from samples with unknown provenance can be classified by principle component analysis as well as by discriminant analysis.