Detection of Cyclospora cayetanensis on bagged pre-cut salad mixes within their shelf-life and after sell by date by the U.S. food and drug administration validated method.

Recently, outbreaks of Cyclospora cayetanensis in the U.S. were linked to the consumption of a variety of salads containing romaine and/or iceberg lettuce, carrots and/or red cabbage. The Bacteriological Analytical Manual (BAM) Chapter 19b method was validated for the detection of C. cayetanensis in carrots, cabbage and romaine lettuce, but has not been previously evaluated in ready-to-eat (RTE) salad mixes. In addition, the only samples available for traceback investigations are sometimes leftovers in bad conditions. This study evaluated the validated BAM method for detection of C. cayetanensis in two different RTE mixed salads (mix 1: romaine and iceberg lettuces, carrots, and red cabbage and mix 2: romaine and iceberg lettuces, carrots, red cabbage, radish, and pea pods) in good condition and after their sell by date. Individual samples (25 g) were seeded with five and 200 C. cayetanensis oocysts. Unseeded produce was used as negative control. The method included washing of the produce, concentration and extraction of C. cayetanensis DNA and molecular detection of C. cayetanensis 18 S rRNA gene. As few as five oocysts were detected in both fresh and after sell by date mix salads. All unseeded samples were negative, and all samples of both salad types seeded with 200 oocysts were positive. In samples seeded with 200 oocysts, average 18 S rRNA C. cayetanensis CT values were significantly higher in fresh salad mix 1 compared to fresh salad mix 2; CT values were significantly higher in the after sell by date salads compared to their respective fresh mixes (p < 0.05). In conclusion, the BAM method was able to detect as few as five oocysts even in after sell by date RTE mix salads. However, the differences in detection observed, highlight the importance of evaluating the performance of the validated C. cayetanensis detection method in different food matrices and conditions, in advance for future outbreak investigations.

Comparison of three common pre-treatment methods for the determination of lead contents by GFAAS in Chinese health-care wines.

Sample pre-treatment plays an important role in sample analysis, which directly affects the accuracy and reliability of the results. In this work we studied the influence of three common sample pre-treatment methods (direct injection, microwave digestion and wet digestion) on the determination of lead (Pb) content of Chinese health-care wines by graphite furnace atomic absorption spectrometry (GFAAS). Six different brands of Chinese health wines were selected for the research. After each Chinese health-care wine was digested by three digestion methods, GFAAS was used to detect the Pb content of the samples. For the selected six different health-care wines, the results showed that the Pb content obtained by GFAAS with different pre-treatment methods were different. Microwave digestion had the best recovery, and was proposed to be applied to the pre-treatment of many kinds of health-care wines, while the direct injection method might be suitable only for health-care wine with lesser amounts of ingredients such as sugar. In the practical work, due to the complexity of the base composition of Chinese health-care wines, currently there is no relevant standard analysis method for the pre-treatment of Chinese health wines. According to the accuracies of the three chosen common pre-treatment methods, it was proposed that microwave digestion might be more suitable as a standard digestion method for the determination of Pb in Chinese health-care wines. This work could provide theoretical support for the further establishment of a standard analytical method for the determination of lead and other (heavy) metal elements in Chinese health wines by GFAAS and other methods.

Development of a Comprehensive Food Literacy Measurement Tool Integrating the Food System and Sustainability.

The concept of food literacy is evolving and expanding, increasing the need for a comprehensive measurement tool for food literacy. This study aimed to develop a validated food literacy questionnaire based on an expanded conceptual framework for food literacy. A literature review of existing frameworks and questionnaires for food literacy and focus group interviews (n = 12) were conducted to develop a conceptual framework and candidate questions. A Delphi study (n = 15) and pilot survey (n = 10) to test the preliminary questionnaire's content and face validity were conducted, which were followed by the main survey (n = 200). Construct validity and reliability were assessed using exploratory factor analysis (EFA) and Cronbach's alpha, respectively. Criterion validity was assessed by comparing food literacy scores with food knowledge scores (FN-score) and nutrient quotient scores (NQ-score). By integrating and revising the six existing conceptual frameworks and focus group interview results, we proposed a two-dimensional conceptual framework comprising a literacy dimension and a food system dimension. After reviewing 560 items and categorizing them into 18 domains (3 in the literacy dimension × 6 in the food system dimension), 32 questions were selected. As a result of the Delphi study, two items were deleted, and content validity was confirmed for the remaining 30 items (content validity ratio (CVR) = 0.92). Ten items were revised during the face validation process, and five items were excluded as a result of the EFA. The final food literacy questionnaire comprised 25 questions related to five factors: production, selection, preparation and cooking, intake, and disposal. Food literacy scores were positively associated with FN- and NQ-scores, confirming the reliability and criterion validity of the final questionnaire. The two-dimensional food literacy conceptual framework developed in this study systematically encompasses complex food literacy concepts by adding a food systems dimension (production, selection, preparation and cooking, intake, and disposal domain) to the existing literacy dimension (functional, interactive, and critical literacy domain). Based on this integrated conceptual framework, a 25-item food literacy questionnaire was developed and validated for practical use.

Development and performance evaluation of a novel dynamic headspace vacuum transfer "In Trap" extraction method for volatile compounds and comparison with headspace solid-phase microextraction and headspace in-tube extraction.

Headspace in-tube extraction (HS-ITEX) and solid phase microextraction (HS-SPME) sampling, followed by gas chromatography-mass spectrometry (GC-MS), are widely used to analyze volatile compounds in various food matrices. While the extraction efficiency of volatile compounds from foodstuffs is crucial for obtaining relevant results, these efficiency of these extraction methods limited by their long extraction times and requirements for large sample quantity. This study reports on the development and application of a new extraction technique based on HS-ITEX hardware, which improves the extraction rate and capacity by operating under reduced pressure, called Dynamic Headspace Vacuum Transfer In-Trap Extraction (DHS-VTT). The results of the study indicate that DHS-VTT improves the extraction of the target compounds. The area of the mass spectrometer signal for each compound can be up to 450 times more intense than the HS-SPME and HS-ITEX techniques performed in the same experimental conditions of extraction temperature and time. DHS-VTT runs in automated mode, making it possible to work with smaller sample quantity and also favors the HS extraction of all volatile compounds. In addition, the necessary modifications to the installation were cheap and the life of an ITEX trap is up to 10 times longer than an SPME fibre.

Research and regulatory gaps for the substantiation of protein content claims on foods.

Protein claims provide guidance to consumers seeking protein-rich foods. Protein claim regulations differ globally, and both Canada and the United States require protein quality assessments. A tripartite workshop identified the need to (i) harmonize, (ii) update existing amino acid composition and digestibility databases, (iii) develop non-animal bioassays, and (iv) evaluate the impact of protein claims on human health. The Protein-Digestibility Corrected Amino Acid Score method is recommended for current regulatory use in Canada.

Non-destructive inspection of food and technical oils by terahertz spectroscopy.

Quality control and non-destructive monitoring are of notable interest of food and pharmaceutical industries. It relies on the ability of non-invasive inspection which can be employed for manufacturing process control. We hereby apply terahertz (THz) time-domain spectroscopy as non-destructive technique to monitor pure and degraded oils as well as hydrocarbon chemicals. Significant differences in the spectra of refractive index (RI) and absorption coefficient arising from the presence of ester linkages in the edible and technical oils were obtained. Explicit increase from 1.38 to 1.5 of the RI in all THz spectrum range was observed in hydrocarbons and mono-functional esters with the increase of molar mass. This fact is in contrast of RI dependence on molar mass in multi-functional esters, such as Adipate or vegetable oils, where it is around 1.54. Degradation products, Oleic Acid (OA) and water in particular, lead only to some changes in absorption coefficient and RI spectra of vegetable oils. We demonstrate that complex colloidal and supramolecular processes, such as dynamics of inverse micelles and oil hydrolysis, take part during oil degradation and are responsible for non-uniform dependence of optical properties on extent of degradation.

Multiresidue determination of pesticides in crop plants by the quick, easy, cheap, effective, rugged, and safe method and ultra-high-performance liquid chromatography tandem mass spectrometry using a calibration based on a single level standard addition in the sample.

In this study, a QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) method, optimized by a 23 full factorial design, was developed for the determination of 72 pesticides in plant parts of carrot, corn, melon, rice, soy, silage, tobacco, cassava, lettuce and wheat by ultra-high-performance liquid chromatographic tandem mass spectrometry (UHPLC-MS/MS). Considering the complexity of these matrices and the need of use calibration in matrix, a new calibration approach based on single level standard addition in the sample (SLSAS) was proposed in this work and compared with the matrix-matched calibration (MMC), the procedural standard calibration (PSC) and the diluted standard addition calibration (DSAC). All approaches presented satisfactory validation parameters with recoveries from 70 to 120% and relative standard deviations≤20%. SLSAS was the most practical from the evaluated approaches and proved to be an effective way of calibration. Method limit of detection were between 4.8 and 48µgkg-1 and limit of quantification were from 16 to 160µgkg-1. Method application to different kinds of plants found residues of 20 pesticides that were quantified with z-scores values≤2 in comparison with other calibration approaches. The proposed QuEChERS method combined with UHPLC-MS/MS analysis and using an easy and effective calibration procedure presented satisfactory results for pesticide residues determination in different crop plants and is a good alternative for routine analysis.

Automatic single-step quick, easy, cheap, effective, rugged and safe sample preparation devices for analysis of pesticide residues in foods.

In this research, the manual two-step QuEChERS approach has been streamlined and automated into a one-step method using a cleanup tube fitted within an extraction tube. A novel automatic QuEChERS combination have been developed to simplify the QuEChERS procedures and improve sample preparation efficiency. This combination integrates QuEChERS procedures into a single run via the use of a vortex vibration-centrifuge device and a centrifuge filtration tube. To validate the efficiency of our automatic QuEChERS device, 270 pesticides were analyzed in plant origined foods including celery, tomatoes, leeks, eggplants, grapes, corn, green tea, and soybean oil using this automatic platform. The results were then compared with those obtained using the manual QuEChERS method. Different parameters were validated and compared including recovery, linearity, repeatability and limits of quantification (LOQ). Satisfactory results, comparable to results obtained using the manual QuEChERS method were obtained. The average recoveries ranged between 70% and 120% for most pesticides with associated relative standard deviations (RSDs) <20% (n=5) indicating satisfactory accuracy and repeatability. An LOQ of 2µg/kg was obtained for most pesticides present in celery and corn matrices, and the correlation coefficients (r2) were >0.990 within a linearity range of 2-500µg/kg. Compared to manual QuEChERS, this novel automatic QuEChERS device and combination could significantly improve the sample preparation efficiency for the multiresidue analysis of pesticides.

Assessment of dietary choices of young women in the contexts of hormonal contraceptives

Background: Metabolic changes caused by hormonal contraception combined with unbalanced diet may pose many threats, and deficiency or excess of nutrients may increase the risk of using such contraceptives. Objective: The purpose of the survey was to assess the dietary choices of young women using hormonal contraceptives, taking into account their general knowledge about the contraception and its impact on their bodies. Material and methods: The survey comprised 67 women aged from 18 to 25 years. In of three-day menus (201 daily food rations) of the women under research the content of energy and most of nutritious ingredients wandered away from recommended values in Poland. Each respondent additionally filled in a questionnaire concerning her: anthropometric data, education, place of residence; the type, name and time of taking contraceptives; purpose for using hormonal contraception along with its determinants; duration of use, breaks in contraceptive practice; occurrence of side effects during contraceptive use; stimulants used; physical activity, incidence of diarrhoea and vomiting, and dietary supplements use. Results: The assessment of nutritional status of young women taking hormonal contraceptives has shown a number of nonconformities. The survey has revealed insufficient energy value of the menus, and incorrect proportions of basic nutrients, from recommended values, what was reflected in insufficient intake of vitamins (A, D, E, C, B1, B3, B6, and folates) and minerals (K, Ca, Mg, Fe). An excessive consumption of proteins, animal-based in particular, and insufficient consumption of lipids and carbohydrates, polysaccharides in particular, what resulted in insufficient consumption of dietary fibre. Conclusions: Nutritional choices of the respondents were typical to their gender and age, but were not adjusted to the use of hormonal contraceptives. Side effects observed by the respondents, mainly weight gain, may have been a summary result of improper eating behaviors that facilitated accumulation of body fat and water.

Assessment of organochlorine pesticide residues in raw food samples from open markets in two African cities.

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.

Assessment of the nutritional composition of quinoa (Chenopodium quinoa Willd.).

Quinoa (Chenopodium quinoa Willd.) is an ancient crop which can play an important role for worldwide food security. The current review aimed at evaluating existing compositional data which were compiled according to international standards. A limited number of data were found that met the dataset quality criteria. In general, high variations in nutrient contents of quinoa were observed per 100g edible portion on fresh weight basis, for example: protein (9.1-15.7g), total fat (4.0-7.6g) and dietary fiber (8.8-14.1g). The variations of nutrient values among different varieties and among different data sources were considerable. The results show the nutritional potential of quinoa but they also demonstrate that more high-quality analytical data of quinoa are needed, especially for minerals and vitamins.

EuroFIR guidelines for assessment of methods of analysis: GAMA.

Analytical methodology is a key factor in food composition databases and specific criteria, at the component level, is needed for comparison of analytical data from different sources. The aim of this work is to describe how EuroFIR guidelines for assessment of methods of analysis are created and made available to users. Comprehensive information for macronutrients, vitamins, minerals and trace elements addressing all aspects of analytical procedures was obtained from international standards, and scientific literature. Documentation was compiled in a confluence wiki format provided for each component: background information, description of reference methods of analysis and critical steps, available reference materials, proficiency testing schemes, other analytical methods and relevant references. The information for each nutrient was collated, edited and presented with hypertext links to additional pages where more detailed information can be accessed using full text searches. The wiki format is a useful tool for preparing information and disseminating to users.

Comparison of accelerated solvent extraction and quick, easy, cheap, effective, rugged and safe method for extraction and determination of pharmaceuticals in vegetables.

Land application of biosolids and irrigation with reclaimed water in agricultural production could result in accumulation of pharmaceuticals in vegetable produce. To better assess the potential human health impact from long-term consumption of pharmaceutical-contaminated vegetables, it is important to accurately quantify the amount of pharmaceuticals accumulated in vegetables. In this study, a quick, easy, cheap, effective, rugged and safe (QuEChERS) method was developed and optimized to extract multiple classes of pharmaceuticals from vegetables, which were subsequently quantified by liquid chromatography coupled to tandem mass spectrometry. For the eleven target pharmaceuticals in celery and lettuce, the extraction recovery of the QuEChERS method ranged from 70.1 to 118.6% with relative standard deviation <20%, and the method detection limit was achieved at the levels of nanograms of pharmaceuticals per gram of vegetables. The results revealed that the performance of the QuEChERS method was comparable to, or better than that of accelerated solvent extraction (ASE) method for extraction of pharmaceuticals from plants. The two optimized extraction methods were applied to quantify the uptake of pharmaceuticals by celery and lettuce growing hydroponically. The results showed that all the eleven target pharmaceuticals could be absorbed by the vegetables from water. Compared to the ASE method, the QuEChERS method offers the advantages of short time and reduced costs of sample preparation, and less amount of organic solvents used. The established QuEChERS method could be used to determine the accumulation of multiple classes of pharmaceutical residues in vegetables and other plants, which is needed to evaluate the quality and safety of agricultural produce consumed by humans.

PAHs in baby food: assessment of three different processing techniques for the preparation of reference materials.

A feasibility study for producing a matrix reference material for selected polycyclic aromatic hydrocarbons (PAHs) in baby food is reported. A commercially available baby food, containing carrots, potatoes, tomato, white beans and meat, was spiked with the so-called 15 + 1 PAHs included in the PAHs priority list for food of the EU, at a mass fraction level of 1 µg/kg. The contaminated baby food was further processed by autoclaving, freezing or freeze drying. The homogeneity of the three materials (bottle-to-bottle variation) and their short-term (4 weeks) and long-term (18 months) stability at different temperatures were assessed. To this end, an analytical method based on a solid-liquid extraction followed by cleaning up with gel permeation chromatography (GPC) and solid phase extraction (SPE) and GC-IDMS determination, was validated in-house. It could be demonstrated that the procedure fulfilled the demands for application to the homogeneity and isochronous stability studies for the candidate reference materials targeted here. All three materials proved to be sufficiently homogeneous for the intended use. Measurements on the autoclaved material provided the most promising results in terms of envisaged shelf life, although freeze drying was also found to be a suitable processing technique for most of the investigated PAHs. These results are an important step towards the development of a matrix reference material for PAHs in a processed food matrix in a presentation very similar to routine samples.

Development of a new cucumber reference material for pesticide residue analysis: feasibility study for material processing, homogeneity and stability assessment.

The feasibility of the production of a reference material for pesticide residue analysis in a cucumber matrix was investigated. Cucumber was spiked at 0.075 mg/kg with each of the 15 selected pesticides (acetamiprid, azoxystrobin, carbendazim, chlorpyrifos, cypermethrin, diazinon, (α + ß)-endosulfan, fenitrothion, imazalil, imidacloprid, iprodione, malathion, methomyl, tebuconazole and thiabendazole) respectively. Three different strategies were considered for processing the material, based on the physicochemical properties of the vegetable and the target pesticides. As a result, a frozen spiked slurry of fresh cucumber, a spiked freeze-dried cucumber powder and a freeze-dried cucumber powder spiked by spraying the powder were studied. The effects of processing and aspects related to the reconstitution of the material were evaluated by monitoring the pesticide levels in the three materials. Two separate analytical methods based on LC-MS/MS and GC-MS/MS were developed and validated in-house. The spiked freeze-dried cucumber powder was selected as the most feasible material and more exhaustive studies on homogeneity and stability of the pesticide residues in the matrix were carried out. The results suggested that the between-unit homogeneity was satisfactory with a sample intake of dried material as low as 0.1 g. A 9-week isochronous stability study was undertaken at -20 °C, 4 °C and 18 °C, with -70 °C designated as the reference temperature. The pesticides tested exhibited adequate stability at -20 °C during the 9-week period as well as at -70 °C for a period of 18 months. These results constitute a good basis for the development of a new candidate reference material for selected pesticides in a cucumber matrix.

Direct medical costs of neonatal respiratory distress syndrome in two specialized public hospitals in Mexico / Costo médico directo del síndrome de dificultad respiratoria neonatal en dos hospitales públicos de alta especialidad en México

Objective. To estimate direct medical costs (DMC) associated with treatment of Respiratory Distress Syndrome (RDS) in newborns (NB) in two specialized public hospitals in Mexico. Materials and methods. The perspective used was health care payer. We estimated DMC associated with RDS management. The pattern of resource use was established by reviewing clinical records. Microcosting and bootstrap techniques were used to obtain the DMC. Estimated costs were reported in 2011 US dollars. Results. Average DMC per RDS event was 14 226 USD. The most significant items that account for this cost were hospitalization (38%), laboratory and diagnostic exams (18%), incubator time (10%), surfactant therapy (7%), and mechanical ventilation (7%). Conclusion. Average DMC in NB with RDS fluctuated in relation to gestational age weight at birth and clinical complications presented by patients during their hospitalization.

Objetivo. Determinar los costos médicos directos (CMD) asociados con el tratamiento del síndrome de dificultad respiratoria (SDR) en recién nacidos pretérmino en dos hospitales públicos de alta especialidad de México. Material y métodos. Se utilizó la perspectiva del pagador de servicios de salud. El uso de recursos se estimó mediante la revisión de expedientes clínicos. Se empleó la técnica de microcosteo y de bootstrap para la obtención de los CMD. Los costos fueron reportados en dólares estadounidenses de 2011. Resultados. El CMD por evento de SDR promedio fue de 14 226 dólares distribuidos entre los costos de hospitalización (38%), laboratorio y exámenes de diagnóstico (18%), tiempo en incubación (10%), terapia con surfactantes (7%) y ventilación mecánica (7%). Conclusión. Los CMD promedio en recién nacidos pretérmino con SDR están relacionados con la edad gestacional, el peso al nacer y las complicaciones clínicas que presentan los pacientes durante su hospitalización.

A novel approach to selecting and weighting nutrients for nutrient profiling of foods and diets.

BACKGROUND: Nutrient profiling of foods is the science of ranking or classifying foods based on their nutrient composition. Most profiling systems use similar weighting factors across nutrients due to lack of scientific evidence to assign levels of importance to nutrients. OBJECTIVE: Our aim was to use a statistical approach to determine the nutrients that best explain variation in Healthy Eating Index (HEI) scores and to obtain ß-coefficients for the nutrients for use as weighting factors for a nutrient-profiling algorithm. DESIGN: We used a cross-sectional analysis of nutrient intakes and HEI scores. PARTICIPANTS: Our subjects included 16,587 individuals from the National Health and Nutrition Examination Survey 2005-2008 who were 2 years of age or older and not pregnant. MAIN OUTCOME MEASURE: Our main outcome measure was variation (R(2)) in HEI scores. STATISTICAL ANALYSES: Linear regression analyses were conducted with HEI scores as the dependent variable and all possible combinations of 16 nutrients of interest as independent variables, with covariates age, sex, and ethnicity. The analyses identified the best 1-nutrient variable model (with the highest R(2)), the best 2-nutrient variable model, and up to the best 16-nutrient variable model. RESULTS: The model with 8 nutrients explained 65% of the variance in HEI scores, similar to the models with 9 to 16 nutrients, but substantially higher than previous algorithms reported in the literature. The model contained five nutrients with positive ß-coefficients (ie, protein, fiber, calcium, unsaturated fat, and vitamin C) and three nutrients with negative coefficients (ie, saturated fat, sodium, and added sugar). ß-coefficients from the model were used as weighting factors to create an algorithm that generated a weighted nutrient density score representing the overall nutritional quality of a food. CONCLUSIONS: The weighted nutrient density score can be easily calculated and is useful for describing the overall nutrient quality of both foods and diets.

Quantitative assessment of the contribution of high resolution mass spectrometric analysis to the reliability of compound confirmation.

Applications of high resolution mass spectrometry (HRMS) in food safety and residue analysis have increased remarkably over the last few years. The high resolution detection of ions reportedly enhances the assay selectivity but quantitative assessment of HRMS contribution to the assay selectivity has not yet been undertaken. We devised a method to assess the impact of instrument resolution on the probability that a spectral assignment to a given compound was made in error. The method allows for evaluating the quality of a spectral assignment based on resolution and the number of fragmentation stages. It thus provides a firm basis for comparing analytical methods performed on very different mass spectrometric instrumental platforms as well as in the context of the current regulatory framework.

Analytical difficulties facing today's regulatory laboratories: issues in method validation.

The challenges facing analytical laboratories today are not unlike those faced in the past, although both the degree of complexity and the rate of change have increased. Challenges such as development and maintenance of expertise, maintenance and up-dating of equipment, and the introduction of new test methods have always been familiar themes for analytical laboratories, but international guidelines for laboratories involved in the import and export testing of food require management of such changes in a context which includes quality assurance, accreditation, and method validation considerations. Decisions as to when a change in a method requires re-validation of the method or on the design of a validation scheme for a complex multi-residue method require a well-considered strategy, based on a current knowledge of international guidance documents and regulatory requirements, as well the laboratory's quality system requirements. Validation demonstrates that a method is 'fit for purpose', so the requirement for validation should be assessed in terms of the intended use of a method and, in the case of change or modification of a method, whether that change or modification may affect a previously validated performance characteristic. In general, method validation involves method scope, calibration-related parameters, method precision, and recovery. Any method change which may affect method scope or any performance parameters will require re-validation. Some typical situations involving change in methods are discussed and a decision process proposed for selection of appropriate validation measures.