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Fourier transform near infrared (FT-NIR) spectroscopy, in combination with principal component-linear discriminant analysis (PC-LDA), was used for tracing the geographical origin of durum wheat samples. The classification model PC-LDA was applied to discriminate durum wheat samples originating from Northern, Central, and Southern Italy (n = 181), and to differentiate Italian durum wheat samples from those cultivated in other countries across the world (n = 134). Developed models were validated on a separated set of wheat samples. Different pre-treatments of spectral data and different spectral regions were selected and compared in terms of overall discrimination (OD) rates obtained in validation. The LDA models were able to correctly discriminate durum Italian wheat samples according to their geographical origin (i.e., North, Central, and South) with OD rates of up of 96.7%. Better results were obtained when LDA models were applied to the discrimination of Italian durum wheat samples from those originating from other countries across the world, having OD rates of up to 100%. The excellent results obtained herein clearly indicate the potential of FT-NIR spectroscopy to be used for the discrimination of durum wheat samples according to their geographical origin.

BACKGROUND Deoxynivalenol (DON) is the most common Fusarium mycotoxin occurring in wheat and wheat‐derived products, with several adverse and toxic effects in animals and humans. Although bran fractions produced by milling wheat have numerous health benefits, cereal bran is the part of the grain with the highest concentration of DON, thus representing a risk for consumers. Increased efforts have been made to develop analytical methods suitable for rapid DON screening. RESULTS The applicability of Fourier transform near‐infrared (FTNIR), or mid‐infrared (FTMIR) spectroscopy, and their combination for rapid analysis of DON in wheat bran, was investigated for the classification of samples into compliant and non‐compliant groups regarding the EU legal limit of 750 µg kg−1. Partial least squares‐discriminant analysis (PLS‐DA) and principal component‐linear discriminant analysis (PC‐LDA) were employed as classification techniques using a cutoff value of 400 µg kg−1 DON to distinguish the two classes. Depending on the classification model, overall discrimination rates were from 87% to 91% for FTNIR and from 86% to 87% for the FTMIR spectral range. The FTNIR spectroscopy gave the highest overall classification rate of wheat bran samples, with no false compliant samples and 18% false noncompliant samples when the PC‐LDA classification model was applied. The combination of the two spectral ranges did not provide a substantial improvement in classification results in comparison with FTNIR. CONCLUSIONS Fourier transform near‐infrared spectroscopy in combination with classification models was an efficient tool to screen many DON‐contaminated wheat bran samples and assess their compliance with EU regulations. © 2018 Society of Chemical Industry

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14The natural co-occurrence of aflatoxins (AFB 1 , AFB 2 , AFG 1 and AFG 2 ) and ochratoxin A 15 (OTA) in dried split ginger purchased from different local markets in Lagos, South West 16 Nigeria has been investigated. A total of 120 ginger samples, 31 collected during the rainy 17 season and 89 during the dry season, were analyzed. Mycotoxins were determined 18 according to the AOAC Official Method 2008.02 based on multi-toxin immunoaffinity 19 column clean up and liquid chromatography quantification. The incidence of contamination 20 with aflatoxins (AFs) and OTA was significantly higher during the rainy season (81% and 21 77%, respectively) than the dry season (46% and 37%, respectively). Average levels of 22 AFs and OTA in positive samples were 3.13 and 5.10 µg/kg in the rainy season (range 23 0.11-9.52 µg/kg and 0.20-9.90 µg/kg) and 1.18 and 2.76 µg/kg (range 0.20-3.57 µg/kg and 24 0.17-12.02 µg/kg) in the dry season, respectively. Furthermore, the levels of AFB 1 detected 25 2 in 7 out of 31 samples (23%) collected during the rainy season were above the European 26 Union (EU) maximum permitted level (i.e. 5 µg/kg). No samples were found above the EU 27 regulatory limits established for OTA in ginger (i.e. 15 µg/kg). Moreover, a higher co-28 occurrence of AFs and OTA was observed in samples collected during the rainy season 29 (65%) than the dry season (21%). Data showed that high humidity and temperature 30 occurring during storage, which are prevalent in the rainy season, offer favorable 31 conditions for AFs and OTA fungal production. This is the first report on the co-occurrence 32 of AFs and OTA in ginger samples from Nigeria. Our results demonstrate that, in order to 33 minimize the risks for consumers, the monitoring of the co-occurrence of these mycotoxins 34 in ginger is highly recommended. 35 36

A fluorescence polarization (FP) immunoassay has been optimized and validated for rapid quantification of T-2 and HT-2 toxins in both unprocessed cereals, including oats, barley and rye, and cereal-based products for direct human consumption, such as oat flakes, oats crispbread and pasta. Samples were extracted with 90 % methanol, and the extract was filtered and diluted with water or sodium chloride solution prior to the FP immunoassay. Overall mean recoveries from spiked oats, rye, barley, oat flakes, oats crispbread and pasta ranged from 101 to 107 %, with relative standard deviations lower than 7 %. Limits of detection (LODs) of the FP immunoassay were 70 μg/kg for oats, 40 μg/kg for oat flakes and barley, 25 μg/kg for pasta and 20 μg/kg for rye and oats crispbread. The trueness of the immunoassay was assessed by using two oat and oat flake reference materials for T-2 and HT-2 toxins, showing good accuracy and precision. Good correlations (r > 0.953) were observed between T-2 and HT-2 toxin contents in naturally and artificially contaminated samples determined by both FP immunoassay and ultra-highperformance liquid chromatography (UHPLC) with immunoaffinity column cleanup used as reference method. These results, combined with rapidity and simplicity of the assay, show that the optimized assay is suitable for high-throughput screening, as well as for reliable quantitative determination of T-2 and HT-2 toxins in cereals and cereal-based products.

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