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Salmonella is one of the major causes of gastroenteritis worldwide in both humans and animals and one of the main agents involved in foodborne disease outbreaks. In this study, 70 raw kibbe samples from different commercial establishments were analyzed for Salmonella spp. The isolates were seroyped and tested for susceptibility to antimicrobial agents. Pulsed-field Gel Electrophoresis was carried out following the standard protocol of the PulseNet network. Fifteen (21.4%) samples were contaminated with Salmonella and S . Give was the prevalent serotype (46.7%). Similarity of 96.3% was observed among the S . Give isolates (n = 7), which indicates the possible spread of the same clone in the analyzed commercial establishments. S . Rissen and S . Typhimurium showed antimicrobial resistance. The detection of a significant percentage of contamination in raw kibbe and of the resistant strains indicates the risk that the consumption of this dish may represent.

The present study was conducted to investigate the effects of raw (PP) and fermented pomegranate pomace (FP) on performance, antioxidant activity, caecal microbiota and ileal morphology in broiler chickens. A total of 175 male broiler chicks were allocated to five treatment groups with five replicates and seven birds per replicate in a completely randomised design. Dietary treatments included a soy-corn based diet (control), diets supplemented with PP at 5 (5PP) and 10 g/kg (10PP), and diets supplemented with FP at 5 (5FP) and 10 g/kg (10FP). Dietary PP and FP did not change the body weight and feed conversion ratio. Moreover, dietary PP and FP did not alter the serum glutathione peroxidase, superoxide dismutase, and catalase levels but decreased malondialdehyde ( p < 0.05) in breast meat. Caecal Clostridium perfringens count was decreased in broiler chickens of groups 10PP, 5FP and 10FP ( p < 0.05). However, PP and FP had detrimental effects on the ileum morphology of broiler chicks. The villus height was decreased in the 10PP, 5FP and 10FP groups compared with the control group ( p < 0.01). Crypt depth was higher in the 5PP and 10FP groups than control and 10PP groups ( p < 0.01). The villus height to crypt depth ratio was also decreased in 5PP, 5FP, and 10FP groups ( p < 0.01). These results suggest that PP and FP have the potential to be used in broiler diets as antioxidant and antimicrobial agents. However, detailed studies should be conducted to investigate the underlying reasons for the detrimental effects on ileal morphology.

In the present study, a total of 112 raw milk samples were collected between October and December of 2018 from dairy farming households in Malawi and analyzed for aflatoxin M1 (AFM1) using VICAM aflatest fluorometry procedure. These data together with the consumption data obtained through a milk consumption frequency questionnaire were used for the calculation of AFM 1 exposure and its association with hepatocarcinoma (HCC) risk in dairy farming population. Average daily milk intake by children and adults were approximately 300 ± 0.07 and 541.7 ± 0.14 mL, respectively. All raw milk samples tested positive to AFM 1 averaging 0.551 μg/L. Probable mean daily exposure to AFM 1 for adults was 4.98 ± 7.25 ng/kg BW/day almost half that of children (8.28 ± 11.82 ng/kg BW/day). Estimated risk of AFM 1 -induced HCC associated with consumption of milk among children and adults were 0.038 and 0.023 cases per 100,000 individuals per year, respectively. Although the results of this investigation suggest a low risk of HCC, other negative health effects of AFM 1 justify its continuous monitoring and update of the risk assessment. This work presents the first insight in the occurrence of AFM 1 in cow milk in Malawi as well as associated AFM 1 exposure in dairy farming population.

Raw egg-based sauces, such as mayonnaise and aioli, are frequently identified as sources of Salmonella during outbreaks of human cases of foodborne gastrointestinal disease. In this study, we surveyed aioli and mayonnaise recipes from different popular food websites to identify potential risk factors that may lead to the survival of Salmonella Typhimurium. In laboratory experiments, different ratios of food acids were used to determine if lemon juice, vinegar, or a combination of both restricted Salmonella Typhimurium culturability. We found that as long as the pH was below 4.2, bacterial culturability was limited. The use of whole egg alone or in combination with egg yolk was also investigated. Sauce preparations containing whole egg exhibited higher pH and supported Salmonella Typhimurium culturability longer than those containing yolk only. Ten restaurant prepared sauces were also obtained to further characterize the effect of preparation variability. Sauce preparations with a pH ≤ 3.8 did not support bacterial culturability after 4 h incubation at any temperature. The higher the pH the longer Salmonella Typhimurium remained culturable. Based on this study, it is recommended that raw egg-based foods are acidified, then stored at room temperature for at least 4 h prior to consumption., (Crown Copyright © 2020. Published by Elsevier Ltd. All rights reserved.)

Over the years, technology has changed the way we produce and have access to our food through the development of applications, robotics, data analysis, and processing techniques. The implementation of these approaches by the food industry ensure quality and affordability, reducing at the same time the costs of keeping the food fresh and increase productivity. A system, as the one presented herein, for raw food categorization is needed in future food industries to automate food classification according to type, the process of algorithm approaches that will be applied to every different food origin and also for serving disabled people. The purpose of this work was to develop a machine learning workflow based on supervised PLS regression and SVM classification, towards automated raw food categorization from FTIR. The system exhibited high efficiency in multi-class classification of 7 different types of raw food. The selected food samples, were diverse in terms of storage conditions (temperature, storage time and packaging), while the variability within each food was also taken into account by several different batches; leading in a classifier able to embed this variation towards increased robustness and efficiency, ready for real life applications targeting to the digital transformation of the food industry.

Fermentation has been reported to improve the utilization of plant ingredients including soybean meal (SBM) by fish, but the detailed mechanism is still poorly understood. This study compared the effects of partial replacement of fish meal (FM) protein with SBM or Enterococcus faecium fermented SBM (EFSM) on the growth, antioxidant status, intestinal microbiota, morphology, and inflammatory responses in turbot (Scophthalmus maximus L.). The FM-based diet was used as the control (CONT). Two experimental diets were formulated in which 45% of the FM protein was replaced with SBM or EFSM. Each diet was fed to triplicate groups of fish (7.57 ± 0.01 g) twice daily for 79 d. Inferior growth performance was observed in SBM group, however, no significant depression was observed in EFSM group compared to the CONT group. The CONT group had the highest values of lysozyme, complement component 3, total antioxidant capacity, superoxide dismutase and catalase, followed by the EFSM group, and the lowest in SBM group. The malondialdehyde content was lowest in the CONT group, followed by the EFSM group, and was highest in the SBM group. Gut morphology showed that SBM diet induced alterations typical for intestinal inflammation including decreased villus and microvillus height, and increased width and inflammatory cell infiltration of the lamina propria. However, the EFSM group alleviated such SBM-induced intestinal pathological disruption. Paralleled with the morphological symptoms, the inflammatory gene expression levels of tumor necrosis factor alpha, interleukin-1 beta and interleukin-8 were highest in the SBM group, followed by the EFSM group, and were lowest in the CONT group. Furthermore, the intestinal microbiota analysis revealed that EFSM group had an overall more similar microbiota with CONT group than SBM group. Specifically, compared with the SBM group, EFSM group significantly enhanced the probiotics Lactobacillus and anti-inflammatory bacterium Faecalibaculum, and inhibited the Vibrio. Collectively, this study indicated that Enterococcus faecium fermentation effectively counteracted the negative effects of SBM by enhancing antioxidant capacity, suppressing inflammatory responses, and modulating gut microbiota in turbot., Competing Interests: Declaration of competing interest The authors declare no conflict of interest., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Diet is a critical determinant of variation in gut microbial structure and function, outweighing even host genetics 1-3 . Numerous microbiome studies have compared diets with divergent ingredients 1-5 , but the everyday practice of cooking remains understudied. Here, we show that a plant diet served raw versus cooked reshapes the murine gut microbiome, with effects attributable to improvements in starch digestibility and degradation of plant-derived compounds. Shifts in the gut microbiota modulated host energy status, applied across multiple starch-rich plants, and were detectable in humans. Thus, diet-driven host-microbial interactions depend on the food as well as its form. Because cooking is human-specific, ubiquitous and ancient 6,7 , our results prompt the hypothesis that humans and our microbiomes co-evolved under unique cooking-related pressures.

There are currently no standardized objective measures to evaluate beef flavor attributes, especially the comparison between raw beef and cooked beef. Beef flavor attribute is one of the most significant parameters for consumers. This study described a predictive model using a 12-ion-sensor array and sensory properties to evaluate beef flavor attributes based on potential. Then the number of sensors was reduced to six via variance of analysis, and these six sensors were reserved with the saturated calomel reference electrode to constitute a new sensor array. Sensitive flavors of each sensor were selected through multiple comparative analysis. Results showed that the accuracy rate of classifying five basic flavors (acidity, sweetness, bitterness, saltiness, freshness) using the new sensor array was 100%. The processing methods used were based on multivariate statistical methods done with the cluster analysis (CA). Results were compared to sensory evaluation using genetic algorithm (GA). From GA, the accuracy rates of raw and cooked beef were 85.0% and 90.0%, which was consistent with the sensory analysis results. Moreover, reducing the number of sensors could decrease the data dimensionality and detection time. Also raw beef instead of cooked beef could be used in flavor attributes evaluation. This model could become an important method for evaluating beef flavor attributes repeatedly and objectively., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Aflatoxin M1 (AFM 1 ) is a hydroxylated metabolite of Aflatoxin B 1 (AFB 1 ). It appears in milk, when lactating animals consume AFB 1 contaminated feed. It is carcinogenic and teratogenic in nature. Present study was planned to determine levels of AFM1 in raw and processed milk. For this, a total of five hundred and seventy milk samples (raw = 340 and processed = 230) were collected from Punjab (province of Pakistan). Processed milk included ultra-heat treated (UHT) (n=105), pasteurized (n=65), dried (n=40) and condensed milk (n=20). Concentration of AFM1 was quantified by direct competitive ELISA technique. Analysis revealed 100 percent incidence of AFM 1 in UHT and pasteurized milk with a mean of 0.35±0.28ng/ml and 0.11±0.03ng/ml respectively. However, 86.66% raw milk samples were tainted with AFM1 with mean of 0.52±0.42ng/ml and 66.66% of dried milk samples with mean of 0.03±0.02ng/ml. However, none of the condensed milk sample was found positive. Data of raw milk contamination was further computed for seasonal variation. Highest prevalence (100%) was observed during autumn season followed by winter (81.81%), summer (80%) and spring season (62.06%) respectively. Furthermore, all mean values except raw milk were below the FDA legislation. Study results indicate the possible adverse effects on health of people of Pakistan. Good agriculture practices (GAP) and regular screening of raw materials of animal feed prior to supplying may help to control AFM 1 levels in milk.

Samples (n = 485) of raw (n = 394) or heat-treated (n = 91) milk of three different species (cow, n = 170; sheep, n = 133; donkey, n = 84), collected 2013-2016 in Western Sicily (Southern Italy), were analyzed for aflatoxin M 1 (AFM 1 ) by enzyme-linked immunosorbent assay (ELISA). Positive ELISA results were further analyzed by HPLC with fluorescence detection. Both methods had a detection limit for AFM 1 in milk of 7 ng kg -1 . ELISA yielded 12.9 and 5% positives in cows and sheep milk, respectively, all samples of donkey milk were negative. Levels of AFM 1 were in most cases at 0.007-< 0.05 μg kg -1 , only two samples (sheep milk) slightly exceeded the European Union maximum level of 0.05 μg kg -1 . Only 6% of the samples were positive for AFM 1 in a concentration range of 0.008-0.15 μg kg -1 . Only milk samples collected directly from farms were positive. Overall, the levels were much lower than previously reported for Southern Italy cow and sheep milk samples purchased in retail stores. The results of this work indicate a continuous improvement of the feeding techniques on dairy farms of Southern Italy, which is essential to ensure consumers' protection.

Rapid characterization of metabolites and risk compounds such as chemical residues and natural toxins in raw food materials such as vegetables, meats, and edible living plants and animals plays an important part in ensuing food quality and safety. To rapidly characterize the analytes in raw food materials, it is essential to develop in situ method for directly analyzing raw food materials. In this work, raw food materials including biological tissues and living samples were placed between an electrode and mass spectrometric (MS) inlet under a strong electrostatic field; analytes were rapidly induced to generate electrospray ionization (ESI) from the sample tip by adding a drop of solvent onto the sample. Therefore, the electrostatic field-induced tip-ESI-MS allows raw samples to avoid contacting high voltage, and thus this method has the advantage for in vivo analysis of food living plants and animals. Metabolite profiling, residues of pesticides and veterinary drugs, and natural toxins from raw food materials have been successfully detected. The analytical performances, including the linear ranges, sensitivity, and reproducibility, were investigated for direct sample analysis. The ionization mechanism of electrostatic field-induced tip-ESI was also discussed in this work., (© 2018 John Wiley & Sons, Ltd.)

The oral bioaccessibility of several essential and toxic elements was investigated in raw and cooked commercially available seafood species from European markets. Bioaccessibility varied between seafood species and elements. Methylmercury bioaccessibility varied between 10 (octopus) and 60% (monkfish). Arsenic (>64%) was the toxic element showing the highest bioaccessibility. Concerning essential elements bioaccessibility in raw seafood, selenium (73%) and iodine (71%) revealed the highest percentages. The bioaccessibility of elements in steamed products increased or decreased according to species. For example, methylmercury bioaccessibility decreased significantly after steaming in all species, while zinc bioaccessibility increased in fish (tuna and plaice) but decreased in molluscs (mussel and octopus). Together with human exposure assessment and risk characterization, this study could contribute to the establishment of new maximum permissible concentrations for toxic elements in seafood by the European food safety authorities, as well as recommended intakes for essential elements., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Objective: We aim to assess the nutritional composition of shelf-stable (SS) human milk and compare the nutritional profile to Holder pasteurized (HP) and raw human milk from the same pool., Methods: Milk samples from 60 mothers were pooled. From this pool, 36 samples were taken; 12 samples were kept raw, 12 samples were HP, and 12 samples were retort processed to create an SS product. Samples were analyzed for percent fat, percent solids, total protein, lactose, amino acids, and thiamine., Results: Percent fat, percent solids, and lactose were similar between raw, HP, and SS samples. Total protein was statistically increased in SS samples when compared to raw (P = 0.005) and HP (P < 0.001) samples, but protein differences were not clinically relevant (raw = 15.1 mg/mL, HP = 14.8 mg/mL, and SS = 15.8 mg/mL). Lysine was the only amino acid impacted by processing, and its destruction increased as heat increased (raw = 0.85 mg/100 mL, HP = 0.77 mg/100 mL, SS = 0.68 mg/100 mL). Total thiamine was significantly decreased in SS samples (0.14 mg/L; P < 0.01) when compared with raw samples (0.24 mg/L) and HP samples (0.26 mg/L)., Conclusions: Macronutrient content is relatively unaffected by processing; Holder pasteurization and retort processing maintain similar fat, lactose, and total protein levels. Lysine and thiamine were significantly decreased by retort processing, but not by Holder pasteurization. Thiamine losses are clinically significant, and fortification may be necessary if SS donor milk is a long-term feeding choice.

Casein micelles are present in bovine milk as colloidal particles with diameters of 20-600 nm, which are complex macromolecular assemblies composed of four distinct types of casein and colloidal calcium phosphate (CCP). Multiple structural models of casein micelles have been proposed based on their biochemical or physical properties and observed using electron microscopy. However, the CCP distribution and crosslinking structure between CCP and casein remain unclear. Therefore, the internal structure of casein micelles in raw milk was observed using cryo-electron microscopy of vitreous sections (CEMOVIS) with high precision at high resolution. The results confirmed that the average casein micelle diameter was about 140 nm, and that the CCP diameter in casein micelles was about 2-3 nm, with an average diameter of 2.3 nm. The distribution of CCP in casein micelles was not uniform, with an average interval between CCPs of about 5.4 nm. Areas containing no black particles (attributed to CCP) were present, with an average size of about 19.1 nm. Considering previous reports, these areas possibly correspond to pores or cavities filled with water. Based on differences in the density of structures in casein micelles, we estimated that some of the casein aggregates were able to connect with CCP in a string.

The present study was performed to assess the level of biologically potent metallic elements (Al, Cd, Cr, Cu, Hg, Mn, Pb and Zn), metalloid (As) and non-metal (Se) in different raw food from open markets in Kinshasa (Democratic Republic of Congo) and Johannesburg (South Africa). Hundred twenty different food samples comprising of cabbage, bean, beef and fish were collected, digested in the microwave system and analysed for trace metals using ICP-OES, ICP-MS and mercury analyser. The obtained results were used to evaluate the health risk of these elements via consumption of foods. The investigation revealed that the mean level of trace elements ranged Al: 1.62 ± 0.32 to 52.10 ± 3.45, As: 1.62 ± 0.32 to 5.33 ± 1.04, Cd: 0.16 ± 0.09 to 3.93 ± 0.12, Cr: 0.58 ± 0.24 to 17.29 ± 2.03, Cu: 0.69 ± 0.15 to 15.70 ± 1.67, Hg: 1.53 ± 0.1 to 2.94 ± 0.23, Mn: 5.34 ± 1.37 to 18.31 ± 3.45, Pb: 0.16 ± 0.09 to 4.14 ± 1.08, Se: 0.18 ± 0.08 to 1.41 ± 0.97, Zn: 5.47 ± 1.83 to 75.12 ± 5.67 mg kg -1 . The average values of As, Cd, Cr, Cu, Hg, Mn, Pb, Se and Zn in raw foods collected from Johannesburg market were significantly higher (p < 0.05) than those from the Kinshasa market. While the highest Al contents (p < 0.05) were found in the food sold in Kinshasa open market. The levels of most studied metals in the raw foods were exceeding the recommended maximum acceptable limit proposed by the Joint FAO/WHO Expert Committee on Food. The combined Target Hazard Quotients (THQ) values for all samples from both markets were greater than 1 which indicates a potential health risk to the local consumer., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Lactadherin is a peripheral glycoprotein of the milk fat globule membrane with several attributed biological activities. In this study, we developed an indirect competitive ELISA to determine lactadherin concentration by using a rabbit polyclonal antiserum. The ELISA was applied to quantify lactadherin in several dairy by-products. Of the products tested, raw and commercial buttermilk had the highest concentrations of lactadherin (6.79 and 5.27 mg/g of product, respectively), followed by commercial butter serum (4.86 mg/g), commercial skim milk (4.84 mg/g), and raw whey (1.20 mg/g). The concentration of immunoreactive lactadherin was also determined in dairy by-products after they were subjected to different technological treatments. Thus, raw products were heat treated at combinations of temperature and time typically used in the dairy industry, and commercial products were hydrolyzed using 3 proteolytic enzyme preparations. Heat treatments of whey and buttermilk resulted in a smaller decrease in lactadherin concentration than did hydrolysis as determined by ELISA and electrophoresis. At high temperatures for long durations, the loss of lactadherin was higher in whey than in buttermilk, with the maximal reduction of around 48% found after treating whey at 72°C for 60 min. Hydrolysis of commercial products with proteolytic enzymes resulted in a marked decrease of immunoreactivity within the first 5 min of treatment, which thereafter was constant throughout 4 h of hydrolysis. These results demonstrate that dairy by-products from milk fat processing are good natural sources of lactadherin, although technological processes have to be considered, because they have different effects on lactadherin content., (Copyright © 2018 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.)

The central Asian Republic of Tajikistan has been an area of extensive historical agricultural pesticide use as well as large scale burials of banned chlorinated insecticides. The current investigation was a four year study of legacy organochlorine pesticides in surface soil and raw foods in four rural areas of Tajikistan. Study areas included the pesticide burial sites of Konibodom and Vakhsh, and family farms of Garm and Chimbuloq villages. These areas were selected to represent a diversity of pesticide disposal histories and to allow assessment of local pesticide contamination in Tajikistan. Each site was visited multiple times and over 500 samples of surface soil and raw foods were collected and analyzed for twenty legacy organochlorine pesticides. Various local food products were sampled to represent the range of raw foods potentially containing residues of banned pesticides, including dairy products, meat, edible plant and cotton seed products. The pesticide analytes included DDTs (DDT, DDD, DDE), lindane isomers (α, β, γ, δ BHC), endosulfan isomers (endosulfan I, II, sulfate), other cyclodienes (aldrin, α and γ chlordanes, dieldrin, endrin, endrin aldehyde and ketone, heptachlor, heptachlor epoxide), and methoxychlor. Pesticide analytes were selected based on availability of commercial standards and known or suspected historical pesticide use and burial. Pesticide contamination was highest in soil and generally low in meat, dairy, and plant products. DDT was consistently the highest measured individual pesticide at each of the four sampling areas, along with BHC isomers and endosulfan II. Soil concentrations of pesticides were extremely heterogeneous at the Vakhsh and Konibodam disposal sites with many soil samples greater than 10 ppm. In contrast, samples from farms in Chimbuloq and Garm had low concentrations of pesticides. Pesticide contamination in raw foods was generally low, indicating minimal transfer from the pesticide sites into local food chains., (Published by Elsevier Ltd.)

Buckwheat cookies with various ingredients for raw food vegan diet are usually prepared by soaking them in water at ambient temperature followed by drying at moderate temperature. The aim of this study was to examine the temperature effect on the microbiological quality, antioxidant properties and oxidative stability of lipids of final dried samples. The mixture of ingredients was soaked for 20 h in distilled water, and then cookies were formed and dried in air-forced oven at constant temperature in the range from 40 to 60 °C. Total viable counts, fungi, yeasts, coliform and aerobic spore-forming bacteria counts were evaluated in dried samples and were found to decrease during drying at 50 and 60 °C. Antioxidant activity was determined by DPPH and ABTS assays, and the former showed the highest value at 40 °C. Superoxide dismutase activity was also higher at 40 °C in comparison with that at 60 °C. The percentage of lipid peroxidation inhibition increased with the increase in drying temperature until 4th day of incubation. While peroxide value was significantly higher in samples dried at 40 °C, TBARS values did not show significant changes during the drying process. The results of this study suggest that drying buckwheat-based cookies at 40 °C retained their good antioxidant properties but represent a potentially serious microbial hazard.

This study investigates the level of organochlorine pesticides in the raw food from open markets in Kinshasa, Democratic Republic of Congo (DRC), and Johannesburg, South Africa. It assesses the potential health risks associated with the organochlorine pesticide residues. The Quick, Easy, Cheap, Effective, Rugged, and Safe (QuEChERS) method has been developed for sample preparation. A total of 120 food samples (beans, cabbage, beef, and fish) were obtained from the open markets. The mean concentrations of organochlorine pesticides in raw foods collected from the Johannesburg market were significantly higher (p < 0.05) than those from the Kinshasa market. DDE recorded the highest mean concentration (253.58 ± 4.78 μg kg -1 ) in beef from Johannesburg, and α-BHC recorded the lowest mean concentration (38.54 ± 7.46 μg kg -1 ) in beans from Kinshasa. The investigation of health risk estimates revealed that the number of organochlorine pesticides exceeded the reference dose in the collected food samples., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Most raw milk Ossau-Iraty cheeses are currently manufactured on-farm using the same commercial streptococcal-lactococcal starter (S1). One way to enhance the microbial diversity that gives raw milk its advantages for cheese-making is to formulate new starters combining diverse, characterized strains. A new starter (OI) combining 6 raw milk strains of lactococci, recently isolated and characterized, was tested in parallel with the current starter by making 12 Ossau-Iraty raw milk cheeses at 3 farmhouses under the conditions prevailing at each farm. Compliance of the sensory characteristics with those expected by the Ossau-Iraty professionals, physicochemical parameters and coliforms were quantified at key manufacturing steps. The new starter OI gave cheeses having proper compliance but having lower compliance than the S1 cheeses under most manufacturing conditions, while managing coliform levels equally well as starter S1. This lower compliance relied more on the absence of Streptococcus thermophilus in starter OI, than on the nature of the lactoccocal strains present in starter OI. The study also shows that variations in 5 technological parameters during the first day of manufacture, within the range of values applied in the 3 farmhouses, are powerful tools for diversifying the scores for the sensory characteristics investigated., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Delvotest® T was evaluated for its capability at detecting residues of 27 antibiotics in raw cow's milk and in some dairy ingredients (skimmed and full-cream milk powders). The kit was used as a screening tool for the qualitative determination of antibiotics from different families in a single test. Results delivered by such a method are expressed as 'positive' or 'negative', referring to the claimed screening target concentration (STC). Validation was conducted according to the European Community Reference Laboratories' (CRLs) residues guidelines of 20 January 2010 and performed by two laboratories, one located in Europe and the other in Asia. Five criteria were evaluated including detection capability at STC, false-positive (FP) rate, false-negative (FN) rate, robustness and cross-reactivity using visual reading and Delvoscan®. STCs were set at or below the corresponding maximum residue limit (MRL), as fixed by European Regulation EC No. 37/2010. Four antibiotics (nafcillin, oxytetracycline, tetracycline and rifaximin) out of 27 had a false-negative rate ranging from 1.7% to 4.9%; however, it was still compliant with the CRLs' requirements. Globally, Delvotest T can be recommended for the analysis of the surveyed antibiotics in raw cow's milk, skimmed and full-cream milk powders. Additional compounds were tested such as sulfamethazine, spiramycin and erythromycin; however, detection at the corresponding MRL was not achievable and these compounds were removed from the validation. Other drugs from the sulfonamide, aminoglycoside or macrolide families not detected by the test at the MRL were not evaluated in this study. Regarding the reliability of this rapid test to milk-based preparations, additional experiments should be performed on a larger range of compounds and samples to validate the Delvotest T in such matrices.

The Thermo Scientific™ SureTect™ Escherichia coli O157:H7 Assay is a new real-time PCR assay which has been validated through the AOAC Research Institute (RI) Performance Tested Methods(SM) program for raw beef and produce matrixes. This validation study specifically validated the assay with 375 g 1:4 and 1:5 ratios of raw ground beef and raw beef trim in comparison to the U.S. Department of Agriculture, Food Safety Inspection Service, Microbiology Laboratory Guidebook (USDS-FSIS/MLG) reference method and 25 g bagged spinach and fresh apple juice at a ratio of 1:10, in comparison to the reference method detailed in the International Organization for Standardization 16654:2001 reference method. For raw beef matrixes, the validation of both 1:4 and 1:5 allows user flexibility with the enrichment protocol, although which of these two ratios chosen by the laboratory should be based on specific test requirements. All matrixes were analyzed by Thermo Fisher Scientific, Microbiology Division, Vantaa, Finland, and Q Laboratories Inc, Cincinnati, Ohio, in the method developer study. Two of the matrixes (raw ground beef at both 1:4 and 1:5 ratios) and bagged spinach were additionally analyzed in the AOAC-RI controlled independent laboratory study, which was conducted by Marshfield Food Safety, Marshfield, Wisconsin. Using probability of detection statistical analysis, no significant difference was demonstrated by the SureTect kit in comparison to the USDA FSIS reference method for raw beef matrixes, or with the ISO reference method for matrixes of bagged spinach and apple juice. Inclusivity and exclusivity testing was conducted with 58 E. coli O157:H7 and 54 non-E. coli O157:H7 isolates, respectively, which demonstrated that the SureTect assay was able to detect all isolates of E. coli O157:H7 analyzed. In addition, all but one of the nontarget isolates were correctly interpreted as negative by the SureTect Software. The single isolate giving a positive result was an E. coli O157:NM isolate. Nonmotile isolates of E. coli O157 have been demonstrated to still contain the H7 gene; therefore, this result is not unexpected. Robustness testing was conducted to evaluate the performance of the SureTect assay with specific deviations to the assay protocol, which were outside the recommended parameters and which are open to variation. This study demonstrated that the SureTect assay gave reliable performance. A final study to verify the shelf life of the product, under accelerated conditions was also conducted.

The Thermo Scientific™ SureTect™ Listeria monocytogenes assay is a real-time PCR assay for the detection of Listeria monocytogenes in food and environmental samples, which was certified during 2013 by the AOAC Research Institute (RI) as Performance Tested Method(SM) (PTM) 061302 for a representative range of key food matrixes and production surfaces. This report details the method modification study, which was conducted during 2014, using the AOAC-RI PTM program to extend the validated matrix claims of the assay in comparison to the reference method detailed in International Organization for Standardization 11290-1:1996, including Amendment 1:2004, to gain certification for raw ground turkey, raw ground pork, pasteurized 2% milk, raw pork sausages, raw cod, pasteurized brie cheese, cooked sliced ham, and bagged lettuce. All matrixes were tested by Thermo Fisher Scientific, Microbiology Division, Basingstoke, UK. In addition, brie cheese, bagged lettuce, and raw cod were analyzed independently by the University of Guelph, Canada, during the AOAC-RI controlled independent laboratory study. Using probability of detection (POD) statistical analysis, a significant difference was demonstrated between the candidate and reference methods for the high spiking level with raw ground pork and brie cheese. For all other matrixes and the low spiked levels for raw ground pork and brie cheese, no significant difference by POD was seen between the two methods during the study.