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The objective of this study is to assess near-infrared (NIR) hyperspectral imaging for the detection of ergot bodies at the particle level in cereal flour. For this study, ground ergot body samples and wheat flour samples as well as mixtures of both from 100 to 500,000 mg kg–1were analysed. Partial least squares discriminant analysis (PLS-DA) models were developed and applied to spectral images in order to detect the ergot body particles. Ergot was detected in 100% of samples spiked at more than 10,000 mg kg–1and no false-positives were obtained with non-contaminated samples. A correlation of 0.99 was calculated between the reference values and the values predicted by the PLS-DA model. For the cereal flours containing less than 10,000 mg kg–1of ergot, it was possible for some samples spiked as low as 100 mg kg–1to detect enough pixels of ergot to conclude that the sample was contaminated. However, some samples were under- or overestimated, which can be explained by the lack of homogeneity in relation to the sampling issue and the thickness of the sample. This study has demonstrated the potential of NIR hyperspectral imaging combined with chemometrics as an alternative solution for discriminating ergot body particles from cereal flour. [ABSTRACT FROM PUBLISHER]

BACKGROUND: Several studies have shown that cherries, especially sour cultivars, contain substantial amounts of phenolic compounds. OBJECTIVE: This study aims to (i) analyze the total phenolic compound (TPC) content and the antioxidant capacity (AC) of a large range of cultivars using the same methodology in one laboratory, and (ii) determine the possible relationship between agronomic characteristics and AC. METHODS: A total of 245 samples including sweet, sour and hybrid cultivars from our collections were harvested at their optimum maturity and characterized according to their TPC, DPPH and ORAC values. RESULTS: The TPC content and DPPH and ORAC values varied greatly among the cherries, with the sour cultivars presenting higher levels than the sweet ones. The PCA plot showed a slight grouping by species and confirmed the high TPC content level in sour cultivars. The bi-colored cultivars had lower TPC and antioxidant capacity (AC) values than dark-colored ones, indicating that coloration could give an indication of the AC of fruits. No significant relationship between the agronomic and chemical properties was highlighted. CONCLUSIONS: Cherry fruits, especially from sour cultivars, represent an important source of bioactive compounds and could attract new interest as a 'functional food'. [ABSTRACT FROM AUTHOR]

In recent years, near-infrared (NIR) hyperspectral imaging has proved its suitability for quality and safety control in the cereal sector by allowing spectroscopic images to be collected at single-kernel level, which is of great interest to cereal control laboratories. Contaminants in cereals include, inter alia, impurities such as straw, grains from other crops, and insects, as well as undesirable substances such as ergot (sclerotium of Claviceps purpurea). For the cereal sector, the presence of ergot creates a high toxicity risk for animals and humans because of its alkaloid content. A study was undertaken, in which a complete procedure for detecting ergot bodies in cereals was developed, based on their NIR spectral characteristics. These were used to build relevant decision rules based on chemometric tools and on the morphological information obtained from the NIR images. The study sought to transfer this procedure from a pilot online NIR hyperspectral imaging system at laboratory level to a NIR hyperspectral imaging system at industrial level and to validate the latter. All the analyses performed showed that the results obtained using both NIR hyperspectral imaging cameras were quite stable and repeatable. In addition, a correlation higher than 0.94 was obtained between the predicted values obtained by NIR hyperspectral imaging and those supplied by the stereo-microscopic method which is the reference method. The validation of the transferred protocol on blind samples showed that the method could identify and quantify ergot contamination, demonstrating the transferability of the method. These results were obtained on samples with an ergot concentration of 0.02 % which is less than the EC limit for cereals (intervention grains) destined for humans fixed at 0.05 %. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

The performance characteristics of a near infrared microscopy (NIRM) method, when applied to the detection of animal products in feedingstuffs, were determined via a collaborative study. The method delivers qualitative results in terms of the presence or absence of animal particles in feed and differentiates animal from vegetable feed ingredients on the basis of the evaluation of near infrared spectra obtained from individual particles present in the sample. The specificity ranged from 86% to 100%. The limit of detection obtained on the analysis of the sediment fraction, prepared as for the European official method, was 0.1% processed animal proteins (PAPs) in feed, since all laboratories correctly identified the positive samples. This limit has to be increased up to 2% for the analysis of samples which are not sedimented. The required sensitivity for the official control is therefore achieved in the analysis of the sediment fraction of the samples where the method can be applied for the detection of the presence of animal meal. Criteria for the classification of samples, when fewer than five spectra are found, as being of animal origin needs to be set up in order to harmonise the approach taken by the laboratories when applying NIRM for the detection of the presence of animal meal in feed. [ABSTRACT FROM AUTHOR]

The occurrence of ergot bodies (sclerotia of Claviceps purpurea) in cereals presents a high toxicity risk for animals and humans due to the alkaloid content. To reduce this risk, the European Commission fixed an ergot concentration limit of 0.1% in all feedstuffs containing unground cereals, and a limit of 0.05% in 'intervention' cereals destined for humans. This study sought to develop a procedure based on near infrared hyperspectral imaging and multivariate image analysis to detect and quantify ergot contamination in cereals. Hyperspectral images were collected using an NIR hyperspectral line scan combined with a conveyor belt. All images consisted of lines of 320 pixels that were acquired at 209 wavelength channels (1100–2400 nm). To test the procedure, several wheat samples with different levels of ergot contamination were prepared. The results showed a correlation higher than 0.99 between the predicted values obtained using chemometric tools such as partial least squares discriminant analysis or support vector machine and the reference values. For a wheat sample with a level of ergot contamination as low as 0.01 %, it was possible to identify groups of pixels detected as ergot to conclude that the sample was contaminated. In addition, no false positives were obtained with non-contaminated samples. The limit of detection was found to be 145 mg/kg and the limit of quantification 341 mg/kg. The reproducibility tests of the measurements performed over several weeks showed that the results were always within the limits allowed. Additional studies were done to optimise the parameters in terms of number of samples analysed per unit of time or conveyor belt speed. It was shown that ergot can be detected using a speed of 1–100 mm/s and that a sample of 250 g can be analysed in 1 min. [ABSTRACT FROM AUTHOR]

At present, European legislation prohibits totally the use of processed animal proteins in feed for all farmed animals (Commission Regulation (EC) No. 1234/2003–extended feed ban). A softening of the feed ban for non-ruminants would nevertheless be considered if alternative methods could be used to gain more information concerning the species origin of processed animal proteins than that which can be provided by classical optical microscopy. This would allow control provisions such as the ban of feeding animals with proteins from the same species or intra-species recycling (Regulation (EC) No. 1774/2002). Two promising alternative methods, near-infrared microscopy (NIRM) and real-time polymerase chain reaction (PCR), were combined to authenticate, at the species level, the presence of animal particles. The paper describes the improvements of the real-time PCR method made to the DNA extraction protocol, allowing five PCR analyses to be performed with the DNA extracted from a single particle. [ABSTRACT FROM AUTHOR]

A revision of European Union's total feed ban on animal proteins in feed will need robust quantification methods, especially for control analyses, if tolerance levels are to be introduced, as for fishmeal in ruminant feed. In 2006, a study conducted by the Community Reference Laboratory for Animal Proteins in feedstuffs (CRL-AP) demonstrated the deficiency of the official quantification method based on light microscopy. The study concluded that the method had to be revised. This paper puts forward an improved quantification method based on three elements: (1) the preparation of permanent slides with an optical adhesive preserving all morphological markers of bones necessary for accurate identification and precision counting; (2) the use of a counting grid eyepiece reticle; and (3) new definitions for correction factors for the estimated portions of animal particles in the sediment. This revised quantification method was tested on feeds adulterated at different levels with bovine meat and bone meal (MBM) and fishmeal, and it proved to be effortless to apply. The results obtained were very close to the expected values of contamination levels for both types of adulteration (MBM or fishmeal). Calculated values were not only replicable, but also reproducible. The advantages of the new approach, including the benefits of the optical adhesive used for permanent slide mounting and the experimental conditions that need to be met to implement the new method correctly, are discussed. [ABSTRACT FROM AUTHOR]

The aim of this work is to show new advances in the analytical methods developed in the frame of the ban of processed animal by-products in compound feed that is currently applied within the European Union. With this aim, studies to develop a quantitative near infrared microscopy (NIRM) approach have been undertaken in order to fulfil future requirements of European legislation like the introduction of tolerance levels that would require for official control purposes the availability of specific quantitative methods. The capabilities of the NIRM method have been improved; no sample preparation is required and the acquisition parameters are optimised. Both the gross and the fine fractions of the samples are considered; the reflexion mode was used to analyse the gross raw fraction and the transmission mode was chosen to analyse the fine raw fraction. Parameters for reflexion analyses were already fixed in our previous studies while those of transmission mode have been determined in the present study. Because particles are too small, it is difficult to mark them; spectra were collected using the mapping technique. Quantitative analyses have been carried out for different percentages of adulteration (0.5, 1, 2 and 5%). Results were depending on the particle size distribution of the feed and of the fish meal which led to experimental values of adulteration varying between 0.13–0.92%, 0.93–3.7%, 2.42–5.83% and 1.95–9.39% for theoretical percentages of adulteration equal to 0.5, 1, 2 and 5%, respectively. The established protocol with the key parameters proposed has to be considered for the development of an accurate method of quantification. [ABSTRACT FROM AUTHOR]

Species-specific detection and detection of groups of species such as ruminants is required according to European legislation dealing with the safe use of animal by-products in animal nutrition. Various methods are applied to the analysis of feed samples for the presence of banned processed animal proteins (PAPs) including meat and bone meal (MBM). Classical microscopy as described in the Commission Directive EC/2003/126 is the only official method to detect the presence of constituents of animal origin in feed, nevertheless some deviating protocols allowed under the old Directive (EC/88/1988) claim to gain comparable results. An inherent limitation of the microscopic method is the lack of species specificity. Immunoassays showed the most promising potential in research projects or intercomparison studies being able to detect ruminant PAPs at a concentration level of 0.5%. The aim of this paper is to present the results of the intercomparison study conducted on behalf of European Commission's Directorate General for Health and Consumer Protection (SANCO) in 2004 to establish whether the two-solvent method would gain comparable results to the current European Method and to evaluate the current capability of immunoassays of determining the species in PAPs present in feed. [ABSTRACT FROM AUTHOR]