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According to Regulation (EU) 1169/2011, restaurants and catering services have to manage the risk of food allergens in the products they offer. One of the sources of hidden allergens in food could come from the cross-contact with surfaces or utensils. In order to gain knowledge about the current situation in such kind of establishments, the occurrence of 3 main allergen residues (milk, egg and gluten) has been evaluated in food-contact surfaces from 50 school canteens during a period of two academic years (2014–2016). The study included not only food-contact surfaces of general use but also surfaces for exclusive use in meals free of specific allergens. These food-contact surfaces were selected and analyzed in situ by using a rapid LFIA test during the visits to kitchens. Leftover sample was sent to a laboratory where an ELISA test was performed to confirm results. Out of 621 analyzed surfaces (213 samples for milk and egg and 195 samples for gluten) none of them were found to content milk with the rapid tests. However, the presence of egg and gluten was detected in 15 and 45% of the food-contact surfaces, respectively. The results obtained with ELISA showed also a low occurrence for milk (6%) but higher for egg (24%) and gluten (57%). It has to be highlighted that for some specific food-contact surfaces the occurrence reached up to 40%. These results indicate that the current cleaning procedures as well as the subsequent manipulation of surfaces are not enough suitable for the control of allergen residues in canteens. Besides, the presence of allergens in food-contact surfaces of exclusive-use to prepare allergen-free meals implies that cross-contaminations might happen, thus increasing the risk of hidden allergens in the final product.

In the last few years awareness for allergen management has increased among operators in the food chain. Since a small quantity of allergenic food can trigger an allergic reaction, accurate information in food product labels is essential for people who suffer from food allergy. A key point to reduce the risk of uncontrolled allergen contamination is to implement a strict and validated cleaning process. In this work a sampling method based on swabbing has been optimized with two analytical methods (ELISA and lateral flow tests) for milk and egg analysis on surfaces. Swab material, extraction buffer composition, temperature, time for recovery and the quantity of the allergen residue on the surfaces have been evaluated and a specific procedure was proposed. The new method has demonstrated a good performance to recover egg or milk proteins from two typical working surfaces (stainless steel or Formica). Egg and milk powder were detected by ELISA at a level as low as 0.04 and 0.2 μg, respectively. However, the detection level with lateral flow tests rose to 0.07 μg for egg powder and 0.6 μg for milk, depending on the kind of surface. On average, repeatability of swabbing method ranged from 18 to 32%. Both methods could be applied for validation the cleaning processes and for a routine verification after cleaning.

Milk by-products such as whey and caseinate are widely used as ingredients or processing aids in food industry. However, since they could cause allergic reactions they are included in Allergen Control Plans. β-Lactoglobulin is the major whey protein and caseins are main proteins in milk. Selection of a unique target to analyze the presence of milk in foods could be insufficient when the source of milk proteins is unknown. A new test based on lateral flow immunocromatography that combines the simultaneous and independent detection of both proteins (β-lactoglobulin and casein) in one rapid test was developed. The assay was validated according to AOAC guidelines being able to detect β-lactoglobulin (0.5 ppm), casein (2 ppm), whey and powder milk (1–5 ppm). No cross-reactivity was found with a panel of 38 food commodities. The method is a rapid and suitable tool to identify milk proteins in processed food, ingredients, and rinsing water.

A new system for the analysis of antimicrobial residues in raw milk was optimized by combining a microbial inhibitor tube test (Eclipse Farm) and a device (e-Reader) that integrates incubation at 65 °C and colour change continuous monitoring. The system determines automatically the end point of the assay and interprets the results in an objective way. Thus, the new method is adapted for the use at farms and small dairies since it simplifies the analysis and increases the accuracy of the results. The performance of a new system was validated according to the European Commission Decision 2002/657/EC. Limits of detection of the new system were firstly evaluated for 30 molecules from several families of antimicrobials and were found to be close to the European maximum residue limits (MRLs). Detection capabilities were also determined for six molecules representing the main antimicrobial groups used in dairy husbandry (penicillins, cephalosporins, tetracyclines, sulphonamides, macrolides and aminoglycosides). All molecules were detected at or below the MRL level. Ruggedness was also studied, demonstrating that the new method was unaffected by reasonable changes in the procedure (sample volume, incubation temperature, test batch). Applicability was demonstrated in raw cow milk regardless fat and protein content or high somatic cell counts. Eclipse Farm coupled to e-Reader has proved to be a valuable tool for the screening of a broad-spectrum of antimicrobial residues in raw milk.

Colostrum addition to milk results in a reduction of the yield during cheese manufacturing. Determination of IgG levels is accepted as an evidence of this troublesome habit due to the high level of this protein in colostrum. This study shows for the first time the IgG levels in bulk ewe's milk samples from Spain throughout the year. IgG quantification was carried out by a sandwich ELISA that recognizes specifically ovine IgG. The mean value of IgG concentration obtained from 481 samples was 0.271 ± 0.253 mg/ml. In general, this value is within the range considered acceptable for mature milk according to quality payment systems. Surprisingly, a high mean concentration was obtained in samples collected in winter, 0.742 ± 0.378 mg/ml, suggesting that births were grouped in that period. These results point up that standardization of ewe's milk production has not been achieved yet. For this reason, determination of immunoglobulin levels periodically would be a good parameter to control milk quality.

Hidden allergens are an important issue at kitchens from restaurants and catering establishments when preparing allergen-free meals. Cross-contact and post-cleaning contamination are the main sources of such problems. In this study, milk, egg and gluten residues were analysed on clean food-contact surfaces to evaluate the effectiveness of cleaning and storage conditions in ten school kitchens. Results showed that using detergent with proteases, rinsing the utensils before use and wash by hand, reduced significantly the occurrence of allergens in kitchen surfaces or utensils. Some storage conditions such as keeping utensils in a cupboard or covered somehow, also protect the utensils from allergen post-contamination.

The Explorer(®) 2.0 tube test is a microbial inhibition test for the screening of antimicrobial residues in food samples. The new e-Reader(®) device coupled to Explorer(®) 2.0 operates by incubation at a selected temperature, determination of the endpoint of the assay and interpretation to generate results. This system was validated for muscle samples according to the European Commission Decision 2002/657/EC. Sensitivity towards 25 substances from several groups of antimicrobials was investigated in a first step. Detection capabilities for six substances representing the six major antimicrobial groups were also determined in bovine muscle. The detection capabilities for amoxicillin (10 µg l(-1)), cefalexin (200 µg l(-1)), doxycyclin (100 µg l(-1)), sulfamethazine (100 µg l(-1)), tylosin (100 µg l(-1)) and neomycin (200 µg l(-1)) were in all cases at or below the maximum residue limit (MRL). Specificity and applicability of the test were demonstrated with muscle samples from four animal species (bovine, porcine, ovine and poultry) and results were found to be satisfactory. Ruggedness was evaluated on negative and spiked samples with sulfamethazine as a representative antimicrobial. Neither false-positives nor false-negatives were detected when varying the sample volume, the time of pre-incubation, the temperature of incubation and the batch of the test. These results prove that Explorer(®) 2.0 coupled to e-Reader(®) is a valuable tool for the screening of a broad range of antimicrobials in muscle. This new methodology simplifies the analysis and increases the accuracy of interpretation of the test results since the endpoint of the assay is automatically determined and results are interpreted objectively.

An interlaboratory collaborative study to validate a colorimetric phosphatase inhibition assay for quantitative determination of the okadaic acid (OA) toxins group in molluscs, OkaTest, was conducted. Eight test materials, including mussels, scallops, clams, and cockles, were analyzed as blind duplicates. Blank samples and materials containing different OA toxin levels ranging from 98 to 275 μg/kg OA equivalents were included. The study was carried out by a total of 16 laboratories from 11 different countries. Values obtained for repeatability relative standard deviations (RSDr) ranged from 5.4 to 11.2% (mean 7.5%). Reproducibility RSD (RSDR) values were between 7.6 and 13.2% (mean 9.9%). The Horwitz ratio (HorRat) values ranged between 0.4 and 0.6. A recovery assay was also carried out using a sample spiked with OA. A mean recovery of 98.0% and an RSD of 14.5% were obtained. The results obtained in this validation study indicate that the colorimetric phosphatase inhibition assay, OkaTest, is suitable for quantitative determination of the OA toxins group. OkaTest could be used as a test that is complementary to the reference method for monitoring the OA toxins group.

Concerns regarding the presence of drug residues in foods include allergic reactions, toxicity, technological problems in fermented products and the development of antibiotic resistance in human pathogens. The analysis of antimicrobial residues in foods is generally carried out, in a first step, through microbiological screening tests. These tests commonly use Geobacillus stearothermophilus as target specie but show a low ability to detect quinolones. The goal of our study was to evaluate the performance of a new microbiological test (Equinox) for detection of quinolone residues in muscle. The kit contains an ampoule with a standardized number of freeze-dried Escherichia coli and must be diluted with a specific detection medium containing a redox indicator. Microbial growth will modify the redox potential of the medium being observed through a colour change (from blue to brown/orange). Equinox limits of detection for most of tested quinolones (enrofloxacin, norfloxacin, sarafloxacin, marbofloxacin, ciprofloxacin, danofloxacin and difloxacin) were below or around maximum residue limit (MRL) UE and CCβ values obtained corresponded with the determined sensitivities. In contrast, flumequine could not be detected at MRL UE levels. Moreover, Equinox displayed a low sensitivity to other antimicrobials. Sensitivity data obtained in vitro were consistent when testing incurred muscle samples. Matrix constituents, test batch and animal species did not affect the performance of the test. Equinox could be easily automated enabling a large numbers of simultaneous analysis, and a photometric reading can be applied for a precise interpretation. The results obtained in this study prove that Equinox is a useful tool when screening for quinolone residues or can be combined with other methods for screening of unknown samples.

Se estudian las bases de datos multimedia en relación con la industria, los contenidos y el usuario multimedia, las políticas de desarrollo, el mercado, los soportes y el acceso, los contenidos y los sectores del mercado; con el almacenamiento masivo; con las aplicaciones a la documentación y la gestión de la información; y, en fin, con las aplicaciones a la formación y a la investigación en multimedia.

Background The Eclipse Farm 4G test coupled to the COMET device allows for automatic and easy screening of a broad range of antimicrobials in raw bovine milk. All results obtained with this system are available in real-time through a smartphone application (App) and in the Test4all cloud platform. Objective The objective of this study was to validate Eclipse Farm 4G & COMET for the screening of antimicrobials in raw bovine milk according to AOAC Performance Tested MethodSM procedures. Method The test is based on the inhibition of microbial growth of Geobacillus stearothermophilus in the presence of antimicrobials. When sample tubes are incubated in the absence of antibiotics, spores germinate and cells grow, changing the medium color from purple to yellow (negative result). The presence of antimicrobials in the milk sample hinders bacterial growth, preventing the tubes from changing color from purple to yellow (positive result). The COMET device automatically integrates all assay steps (incubation, time control, and results interpretation) and communications between the device, smartphone, and cloud. Results LODs and detection capabilities were confirmed to be at or below the European Union (EU) maximum residue limit (MRL) for most of the evaluated molecules representing the main families of antimicrobials (penicillins, cephalosporins, tetracyclines, sulfonamides, macrolides, and aminoglycosides). False-positive rates and the effect of potentially interfering substances showed sufficient selectivity/specificity. The Eclipse Farm 4G & COMET system was shown to be robust, consistent, and stable during shelf life. Conclusions The Eclipse Farm 4G & COMET system has been shown to be suitable for screening antibiotics in raw bovine milk. Highlights The assay is an automatic and easy system for the detection of a broad range of antibiotics in raw bovine milk consistent with EU MRLs and can provide results any time and anywhere through a smartphone App and a cloud platform.