854 resultados para Food Analysis


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A multiresidue gas chromatographic method for the determination of six fungicides (captan, chlorthalonil, folpet, iprodione, procymidone and vinclozolin) and one acaricide (dicofol) in still and fortified wines was developed. Solid-phase microextraction (SPME) was chosen for the extraction of the compounds from the studied matrices and tandem mass spectrometry (MS/MS) detection was used. The extraction consists in a solvent free and automated procedure and the detection is highly sensitive and selective. Good linearity was obtained with correlation coefficients of regression (R2) > 0.99 for all the compounds. Satisfactory results of repeatability and intermediate precision were obtained for most of the analytes (RSD < 20%). Recoveries from spiked wine ranged from 80.1% to 112.0%. Limits of quantification (LOQs) were considerably below the proposedmaximumresidue limits (MRLs) for these compounds in grapes and below the suggested limits for wine (MRLs/10), with the exception of captan.

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An accurate and sensitive method for determination of 18 polycyclic aromatic hydrocarbons (PAHs) (16 PAHs considered by USEPA as priority pollutants, dibenzo[a,l]pyrene and benzo[j]fluoranthene) in fish samples was validated. Analysis was performed by microwave-assisted extraction and liquid chromatography with photodiode array and fluorescence detection. Response surface methodology was used to find the optimal extraction parameters. Validation of the overall methodology was performed by spiking assays at four levels and using SRM 2977. Quantification limits ranging from 0.15–27.16 ng/g wet weight were obtained. The established method was applied in edible tissues of three commonly consumed and commercially valuable fish species (sardine, chub mackerel and horse mackerel) originated from Atlantic Ocean. Variable levels of naphthalene (1.03–2.95 ng/g wet weight), fluorene (0.34–1.09 ng/g wet weight) and phenanthrene (0.34–3.54 ng/g wet weight) were detected in the analysed samples. None of the samples contained detectable amounts of benzo[a]pyrene, the marker used for evaluating the occurrence and carcinogenic effects of PAHs in food.

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QuEChERS method was evaluated for extraction of 16 PAHs from fish samples. For a selective measurement of the compounds, extracts were analysed by LC with fluorescence detection. The overall analytical procedure was validated by systematic recovery experiments at three levels and by using the standard reference material SRM 2977 (mussel tissue). The targeted contaminants, except naphthalene and acenaphthene, were successfully extracted from SRM 2977 with recoveries ranging from 63.5–110.0% with variation coefficients not exceeding 8%. The optimum QuEChERS conditions were the following: 5 g of homogenised fish sample, 10 mL of ACN, agitation performed by vortex during 3 min. Quantification limits ranging from 0.12– 1.90 ng/g wet weight (0.30–4.70 µg/L) were obtained. The optimized methodology was applied to assess the safety concerning PAHs contents of horse mackerel (Trachurus trachurus), chub mackerel (Scomber japonicus), sardine (Sardina pilchardus) and farmed seabass (Dicentrarchus labrax). Although benzo(a)pyrene, the marker used for evaluating the carcinogenic risk of PAHs in food, was not detected in the analysed samples (89 individuals corresponding to 27 homogenized samples), the overall mean concentration ranged from 2.52 l 1.20 ng/g in horse mackerel to 14.6 ± 2.8 ng/ g in farmed seabass. Significant differences were found between the mean PAHs concentrations of the four groups.

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This study was developed with the purpose to investigate the effect of polysaccharide/plasticiser concentration on the microstructure and molecular dynamics of polymeric film systems, using transmission electron microscope imaging (TEM) and nuclear magnetic resonance (NMR) techniques. Experiments were carried out in chitosan/glycerol films prepared with solutions of different composition. The films obtained after drying and equilibration were characterised in terms of composition, thickness and water activity. Results show that glycerol quantities used in film forming solutions were responsible for films composition; while polymer/total plasticiser ratio in the solution determined the thickness (and thus structure) of the films. These results were confirmed by TEM. NMR allowed understanding the films molecular rearrangement. Two different behaviours for the two components analysed, water and glycerol were observed: the first is predominantly moving free in the matrix, while glycerol is mainly bounded to the chitosan chain. (C) 2013 Elsevier Ltd. All rights reserved.

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This study analysed 22 strawberry and soil samples after their collection over the course of 2 years to compare the residue profiles from organic farming with integrated pest management practices in Portugal. For sample preparation, we used the citrate-buffered version of the quick, easy, cheap, effective, rugged, and safe (QuEChERS) method. We applied three different methods for analysis: (1) 27 pesticides were targeted using LC-MS/MS; (2) 143 were targeted using low pressure GC-tandem mass spectrometry (LP-GC-MS/MS); and (3) more than 600 pesticides were screened in a targeted and untargeted approach using comprehensive, two-dimensional gas chromatography time-of-flight mass spectrometry (GC × GC-TOF-MS). Comparison was made of the analyses using the different methods for the shared samples. The results were similar, thereby providing satisfactory confirmation of both similarly positive and negative findings. No pesticides were found in the organic-farmed samples. In samples from integrated pest management practices, nine pesticides were determined and confirmed to be present, ranging from 2 μg kg−1 for fluazifop-pbutyl to 50 μg kg−1 for fenpropathrin. Concentrations of residues in strawberries were less than European maximum residue limits.

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Sulfamethoxazole (SMX) is among the antibiotics employed in aquaculture for prophylactic and therapeutic reasons. Environmental and food spread may be prevented by controlling its levels in several stages of fish farming. The present work proposes for this purpose new SMX selective electrodes for the potentiometric determination of this sulphonamide in water. The selective membranes were made of polyvinyl chloride (PVC) with tetraphenylporphyrin manganese (III) chloride or cyclodextrin-based acting as ionophores. 2-nitrophenyl octyl ether was employed as plasticizer and tetraoctylammonium, dimethyldioctadecylammonium bromide or potassium tetrakis (4-chlorophenyl) borate was used as anionic or cationic additive. The best analytical performance was reported for ISEs of tetraphenylporphyrin manganese (III) chloride with 50% mol of potassium tetrakis (4-chlorophenyl) borate compared to ionophore. Nersntian behaviour was observed from 4.0 × 10−5 to 1.0 × 10−2 mol/L (10.0 to 2500 µg/mL), and the limit of detection was 1.2 × 10−5 mol/L (3.0 µg/mL). In general, the electrodes displayed steady potentials in the pH range of 6 to 9. Emf equilibrium was reached before 15 s in all concentration levels. The electrodes revealed good discriminating ability in environmental samples. The analytical application to contaminated waters showed recoveries from 96 to 106%.

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A gold nanoparticle-coated screen-printed carbon electrode was used as the transducer in the development of an electrochemical immunosensor for Ara h 1 (a major peanut allergen) detection in food samples. Gold nanoparticles (average diameter=32 nm) were electrochemically generated on the surface of screen-printed carbon electrodes. Two monoclonal antibodies were used in a sandwich-type immunoassay and the antibody–antigen interaction was electrochemically detected through stripping analysis of enzymatically (using alkaline phosphatase) deposited silver. The total time of the optimized immunoassay was 3 h 50 min. The developed immunosensor allowed the quantification of Ara h 1 between 12.6 and 2000 ng/ml, with a limit of detection of 3.8 ng/ml, and provided precise (RSD <8.7%) and accurate (recovery >96.6%) results. The immunosensor was successfully applied to the analysis of complex food matrices (cookies and chocolate), being able to detect Ara h 1 in samples containing 0.1% of peanut.

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This paper aims to provide strategies for the organic supermarket chain “Alnatura” to shape the demand and its market share of the organic food & beverage (F&B) market in Germany within the next five years. Through the historic evolution and the current market assessment of Germany, compared to a benchmark country (US), as well as prospective trends in Germany, reasons and opportunities for market growth are evaluated. In addition, an industry attractiveness, competitor and company analysis is executed. Based on those findings and a conducted survey, suggestions to adjust Alnatura´s current business strategies are deduced and finally examined on its risk and feasibility.

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There is a rising demand for local food which traveled only short distances and is marketed directly by the producer. With growing importance of local food also the amount of literature in this field increased. Yet, literature is lacking to examine the challenges and burdens consumers face while trying to purchase local food. Evidence is shown that a gap exists between the intention of consumers who would like to purchase local food and their actual behavior. However, reasons for this gap are only discovered as byproducts of other research objectives. Consequently, this study investigates the specific reasons for the intention-behavior gap of consumers in the local food market. The study makes use of semi-structured face-to-face interviews with rural and urban respondents. The interviews are analyzed by qualitative content analysis based on Elo and Kyngäs (2008). Revealed key drivers for the intention-behavior gap are (1) the lack of awareness where to purchase local food products, (2) the limited reachability of local food producers, (3) the assortment of the local producer in regard to size and composition and (4) the lack in transparency of the prices of local food. Consequently, it is the producers turn to eliminate the revealed barriers by proactively bringing their products closer to the consumer.

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BACKGROUND: Children with atopic diseases in early life are frequently found with positive IgE tests to peanuts/tree nuts without a history of previous ingestion. We aimed to identify risk factors for reactions to nuts at first introduction. METHODS: A retrospective case-note and database analysis was performed. Recruitment criteria were: patients aged 3-16 yr who had a standardized food challenge to peanut and/or tree nuts due to sensitisation to the peanut/tree nut (positive spIgE or SPT) without previous consumption. A detailed assessment was performed of factors relating to food challenge outcome with univariate and multivariate logistic regression analysis. RESULTS: There were 98 food challenges (47 peanut, 51 tree nut) with 29 positive, 67 negative and 2 inconclusive outcomes. A positive maternal history of allergy and a specific IgE >5 kU/l were strongly associated with a significantly increased risk of a positive food challenge (OR 3.73; 95% CI 1.31-10.59; p = 0.013 and OR 3.35; 95% CI 1.23-9.11; p = 0.007, respectively). Adjusting for age, a three year-old with these criteria has a 67% probability of a positive challenge. There was no significant association between types of peanut/tree nut, other food allergies, atopic conditions or severity of previous food reactions and positive challenges. CONCLUSIONS: We have demonstrated an association between the presence of maternal atopic history and a specific IgE >5 kU/l, with a significant increase in the likelihood of a positive food challenge. Although requiring further prospective validation these easily identifiable components should be considered when deciding the need for a challenge.

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Whole-grain foods are touted for multiple health benefits, including enhancing insulin sensitivity and reducing type 2 diabetes risk. Recent genome-wide association studies (GWAS) have identified several single nucleotide polymorphisms (SNPs) associated with fasting glucose and insulin concentrations in individuals free of diabetes. We tested the hypothesis that whole-grain food intake and genetic variation interact to influence concentrations of fasting glucose and insulin. Via meta-analysis of data from 14 cohorts comprising ∼ 48,000 participants of European descent, we studied interactions of whole-grain intake with loci previously associated in GWAS with fasting glucose (16 loci) and/or insulin (2 loci) concentrations. For tests of interaction, we considered a P value <0.0028 (0.05 of 18 tests) as statistically significant. Greater whole-grain food intake was associated with lower fasting glucose and insulin concentrations independent of demographics, other dietary and lifestyle factors, and BMI (β [95% CI] per 1-serving-greater whole-grain intake: -0.009 mmol/l glucose [-0.013 to -0.005], P < 0.0001 and -0.011 pmol/l [ln] insulin [-0.015 to -0.007], P = 0.0003). No interactions met our multiple testing-adjusted statistical significance threshold. The strongest SNP interaction with whole-grain intake was rs780094 (GCKR) for fasting insulin (P = 0.006), where greater whole-grain intake was associated with a smaller reduction in fasting insulin concentrations in those with the insulin-raising allele. Our results support the favorable association of whole-grain intake with fasting glucose and insulin and suggest a potential interaction between variation in GCKR and whole-grain intake in influencing fasting insulin concentrations.

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This thesis undertakes an exploration of the nature of alternative food projects in Niagara. A review of various theoretical approaches to the study of food and agriculture, suggests that actor-network theory offers the most useful lens through which to understand these projects. In particular, actor-network theory facilitates non-dualistic theorisations of power and scale and a commitment to the inclusion of non-humans in the 'social' sciences. The research is based on 19 in-depth interviews with actors involved in various urban and rural projects including community supported agriculture, community gardens, chefs using local seasonal food, a winery that grows organically, the good food box, a value-added small business, and organic producers. The analysis consists of four themes. The first analytical section pays special attention to the prominence of agri-tourism in Niagara, and examines the ways in which the projects in the sample interact with agri-tourist networks. In the second section the discussion focuses on the discourses and practices of resistance among Niagara alternative food actors. The participants' interviews suggest there are more discourses of resistance toward agri-tourist than toward dominant food networks. The third section questions commodity chain theorisations of alternative food projects. In particular, this section shows how the inclusion of non-human actors in an analysis confounds conceptualisations of 'short' and 'local' chains. The final analytical section assesses relations of power in Niagara alternative food projects. Three important conclusions arise from this research. First, Niagara alternative food projects cannot be conceptualised as operating at the 'local' scale. Broadening the scope of analysis to include non-human actors, it becomes apparent that these projects actually draw on a variety of extra-local actors. They are at once local and global. Second, the projects in this sample are simultaneously part of alternative, dominant and agri-tourist networks. While Niagara alternative food projects do perform many of the roles characteristic of alternative food systems, they are also involved in practices of development, business, and class distinction. Thus, alternative food networks should not be understood as separate from and in direct opposition to dominant food networks. Despite the second conclusion, this research determines that Niagara alternative food projects have made significant strides in the reworking of power. The projects represented in this thesis do engage in resistant practices and are associated with increased levels ofjustice.

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School of Industrial Fisheries, Cochin University of Science and Technology

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In India, Food Security meant supply of food grains and the medium was Public Distribution System. Public Distribution System (PDS) is a rationing mechanism that entitles households to specified quantities of selected commodities at subsidized prices. The Objectives of PDS are maintaining Price Stability, rationing during times of scarcity, welfare of the poor, and keeping a check on private trade. Kerala has registered remarkable improvement in poverty reduction in general over the years among all social sections, including scheduled caste and scheduled tribe population. As part of the structural adjustment intended to reduce public expenditure, PDS has been modified as Revamped PDS (RPDS) during 1992 and later on as Targeted PDS (TPDS) in 1997, intended to target households on the basis of income criterion, classifying people as Below Poverty Line (BPL) and Above Poverty Line (APL). TPDS provides 25Kg. of food gra.ins through the Fair Price Shops per month @ Rs.3/- per Kg. of rice/ wheat to the BPL category and @Rs.8.90 and Rs.6.7O for rice and wheat respectively to the APL category of people. Since TPDS is intended to target the poor people, the subsidy spent by the government for the scheme should be beneficial to the poor people and naturally they should utilize the benefits by purchasing the food grains allotted under the scheme. Several studies have shown that there is underutilization of the allotments under TPDS. Therefore, the extent of utilization of TPDS in food grains, how and why remains as a major hurdle, in improving the structure and system of PDS. Livelihood of the tribal population being under threat due to increasing degradation of the resources, the targeting system ought to be effective among the tribal population. Therefore, performance of the TPDS in food grains, in terms of the utilization by the tribal population in Kerala, impact thereof and the factors, if any, affecting proper utilization were considered as the research problem in this study. The study concentrated on the pattern of consumption of food grains by the tribal people, whether their hunger needs are met by distribution of food grains through the TPDS, extent to which TPDS in food grains reduce their share of expenditure on food in the total household expenditure, and the factors affecting the utilization of the TPDS in food grains by the tribal population. Going through the literature, it has been noted that only few studies concentrated on the utilization of TPDS in food grains among the tribal population in Kerala.The Research Design used in this study is descriptive in nature, but exploratory in some aspects. Idukki, Palakkad and Wayanad have more than 60% of the population of the tribals in the state. Within the three districts mentioned above, 14 villages with scheduled tribe concentration were selected for the study. 95 tribal colonies were selected from among the various tribal settlements. Collection of primary data was made from 1231 households with in the above tribal colonies. Analysis of data on the socio-economic factors of the tribal people, pattern of food consumption, extent of reduction in the share of expenditure on food among the household expenditure of the tribal people and the impact of TPDS on the tribal families etc. and testing of hypotheses to find out the relation/association of each of the six variables, using the data on BPL and APL categories of households separately have resulted in findings such as six percent of the tribal families do not have Ration Cards, average per capita consumption of food grains by the tribal people utilizing TPDS meets 62% of their minimum requirement, whereas the per capita consumption of food grains by the tribal people is higher than the national average per capita consumption, 63% deficiency in food grains may be felt by tribal people in general, if TPDS is withdrawn, and the deficit for BPL tribal people may be 82%, TPDS facilitates a reduction of 9.71% in the food expenditure among the total household expenditure of the tribal people in general, share of food to non-food among BPL category of tribals is 55:45 and 40:60 among the APL, Variables, viz. household income, number of members in the family and distance of FPS from tribal settlements etc. have influence on the quantity of rice being purchased by the tribal people from the Fair Price Shops, and there is influence of household income and distance of FPS from tribal settlements on the quantity of rice being purchased by the tribal people from the open market. Rationing with differential pricing on phased allotments, rectification of errors in targeting, anomalies in norms and procedures for classifying tribal people as BPL/APL, exclusive Income Generation for tribal population, paddy cultivation in the landholdings possessed by the tribal people, special drive for allotment of Ration Cards to the tribal people, especially those belonging to the BPL category, Mobile Fair Price Shops in tribal settlements, ensure quality of the food grains distributed through the TPDS, distribution of wheat flour in packed condition instead of wheat through the Fair Price Shops are recommended to address the shortcomings and weaknesses of the TPDS vis-avis the tribal population in Kerala.

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The article examines the commodity chain trap of marine fishery in Kerala, at both material and value terms, and its ramifications in the globalised fishery chains. The marketing chains both material and value, are very complex in nature since they involve many types of markets and large number of intermediaries and participants. The article also scrutinizes the sensitivity of consumers’ and country’s responses in terms of dietary and hygienic standards relating to seafood trade. In addition, it discusses the devastating effect about the recent stipulations like the US Bio- Terrorism Act and Shrimp anti-dumping duty on the Kerala fishery products