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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Policy responses to reduce the opportunity for horsemeat adulteration fraud: the case of the European Union

Kulas, Megan January 1900 (has links)
Master of Science / Department of Diagnostic Medicine/Pathobiology / Justin Kastner / Food production is changing in response to an expanding global population. The ability to distribute and process ingredients amongst many individuals and countries has brought economic benefits while also creating new problems. By increasing the complexity of the supply chain, the food industry has birthed new dynamics, thus creating new opportunities for contamination, fraud, and other threats. One threat dynamic is the varying levels of food safety and quality control at different nodes along a supply chain. Contaminations pinpoint weaknesses of a supply chain, and such weaknesses could be exploited for harm. One way foods are intentionally contaminated is through food fraud. Food fraud involves substitution, mislabeling, dilution, and other means of criminal deception. Routine testing by an independent science-based group led to the discovery of one the largest scales of substitution and mislabeling in history—the 2013 adulteration of beef products with horsemeat. Commonly referred to as the horsemeat scandal of 2013, this important event in the history of the global food system affected several regions, hundreds of products, and thousands of retailers and consumers. To date, this scandal was one of the largest incidents of food fraud. Mostly based in the European Union, the horsemeat scandal prompted the European Commission to take regulatory action. The European Union’s policy response included the creation of a five-point plan that addresses the different facets associated with the scandal. The five-point plan sought to strengthen food fraud prevention; testing programs; horse passports; official control, implementation, penalties; and origin labelling. The five-point plan is intended to decrease the fraud opportunity for the adulteration of beef with horsemeat. According to the crime triangle, a concept frequently cited in the field of criminology, fraud opportunity has three main elements: the victims, the fraudsters, and the guardian and hurdle gaps. When any of these elements change, the opportunity for a fraudster to commit a crime also changes. The research question of this thesis explores the policy responses of the European Commission. The Commission’s five-point plan targets the three elements of fraud opportunity; therefore, future fraud opportunity for the adulteration of beef products with horsemeat will theoretically decrease.
12

Validação da metodologia de infravermelho com transformada de Fourier para identificação de adulteração em leite cru / Validation of the Fourier Transform Infrared spectroscopy to identify adulteration of raw milk

Cassoli, Laerte Dagher 08 October 2010 (has links)
Objetivou-se avaliar a utilização da metodologia de infravermelho com transformada de Fourier (IVTF) na identificação de adulteração em leite cru. O objetivo no primeiro estudo foio de desenvolver calibração para identificação de adulteração através da comparação do espectro de leite adulterado com um espectro de referência para leite cru. Para construção do espectro referência foram coletadas 800 amostras de diferentes fazendas localizadas na região de estudo no período de agosto de 2009 a março de 2010. Através da análise de componentes principais, foram desenvolvidas oito calibrações com diferentes números de fatores (componentes principais). Para validação das diferentes calibrações, foram coletadas outras 100 amostras da mesma região de estudo. As amostras foram adulteradas com três diferentes adulterantes geralmente utilizados na adulteração do leite cru sendo eles: bicarbonato de sódio (BS), citrato de sódio (CS) e soro de queijo (SO). Para cada adulterante foram utilizadas três diferentes concentrações (BS: 0,05, 0,10 e 0,25 %; CS: 0,025, 0,050 e 0,075% e SO: 5, 10 e 20%). Para avaliação do desempenho das calibrações foram calculadas a especificidade e a sensibilidade para cada adulterante e respectivas concentrações. A especificidade foi de 92,9% na calibração com 12 fatores. Já a sensibilidade variou em função do adulterante, concentração e número de fatores. Todas as amostras adulteradas com bicarbonato foram identificadas corretamente com modelos de 10 fatores e na concentração mais baixa (0,05%). Já para o citrato, somente amostras com concentração de 0,075% foram identificadas em 93,9% dos casos para o modelo de 18 fatores. Amostras adulteradas com soro, mesmo na concentração mais alta (20%) puderam ser identificadas em menos de 47,1% dos casos, talvez pelo tratamento espectral realizado pelo software ASM em que parte do espectro não é considerado na construção das calibrações. A comparação espectral mostrou-se uma técnica interessante para identificação de leite adulterado e que também poderia antecipar a descoberta de novos adulterantes. Já no segundo estudo o objetivo foi desenvolver calibrações para determinação da concentração dos adulterantes bicarbonato de sódio, citrato de sódio e soro de queijo. Para desenvolvimento das calibrações foram utilizadas as amostras adulteradas do primeiro estudo e, para validação, foram coletadas outras 60 amostras que foram novamente adulteradas. O desempenho de cada calibração foi avaliado através da acurácia (Se), limite de detecção (LD) e coeficiente de determinação (R2). Todas as calibrações apresentaram R2 superior a 0,91 com LD de 0,015%, 0,017% e 3,9% para BS, CS e SO, respectivamente. Já a acurácia foi de 0,005%, 0,009 % e 2,26% para BS, CS e SO, respectivamente. Através dos resultados obtidos neste estudo, conclui-se que a metodologia de IVTF pode ser utilizada para determinação da concentração de bicarbonato de sódio, citrato de sódio e soro de queijo em leite cru. Associada à equipamentos automatizados, é uma opção viável no monitoramento destes adulterantes, tendo o baixo custo operacional e alto desempenho analítico como características adicionais. / The objective of this research was to evaluate the use of the methodology of Fourier Transform Infrared (FTIR) in identifying adulteration in raw milk. The objective of the first study was to develop scales to identify contamination by comparing the spectrum of adulterated milk with a reference spectrum for raw milk. To build the reference spectrum, 800 samples were collected from different farms located in the study area from August 2009 to March 2010. Through the analysis of principal components, eight scales with different numbers of factors (principal components) were developed. To validate the different calibrations, other 100 samples were collected from the same region of study. The samples were adulterated with three different adulterants commonly used in the adulteration of raw milk: sodium bicarbonate (SB), sodium citrate (SC) and whey (W). Each adulterant was used at three different concentrations (SB: 0.05, 0.10 and 0.25%; SC: 0.025, 0.050 and 0.075% and W: 5, 10 and 20%). To evaluate the performance of the calibrations, the specificity and sensitivity for each adulterant and its concentration were calculated. The specificity was 92.9% in the calibration with 12 factors. Sensitivity varied according to the adulterant, concentration and number of factors. All samples adulterated with bicarbonate were accurately identified in the 10-factor model and at the lowest concentration (0.05%). As for citrate, only samples at a concentration of 0.075% were identified in 93.9% of cases for the 18-factor model. Samples adulterated with whey, even at the highest concentration (20%) were identified in less than 47.1% of cases, which maybe attributed to the fact that part of the spectrum is not consideredin the spectral processing performed by ASM software. The spectral comparison proved to be an interesting technique for the identification of adulterated milk and that could also be used to discover new adulterants. In the second study, the aim was to develop calibrations for determining the concentration of sodium bicarbonate, sodium citrate and whey used as raw milk adulterants. To develop the calibrations, adulterated samples of the first study were used and, for validation, other 60 samples were collected and adulterated. The performance of each calibration was evaluated regarding accuracy (Se), detection limit (DL) and determination coefficient (R2). All calibrations presented R2 higher than 0.91 with DL of 0.015%, 0.017% and 3.9% for SB, SC and W, respectively. Accuracy was 0.005%, 0.009% and 2.26% for SB, SC and W, respectively. Results show that the FTIR methodology can be used for determining the concentration of sodium bicarbonate, sodium citrate and whey in raw milk. Associated with automated equipment, it is a feasible option for monitoring these adulterants, presenting low operational costs and high analytical performance as additional features.
13

'Waiter! There's a fly in my soup - or is that a cockroach?': the moral panic of dirty restaurants in the city of Toronto, Canada /

Leung, Cherie January 1900 (has links)
Thesis (M.A.) - Carleton University, 2005. / Includes bibliographical references (p. 68-74). Also available in electronic format on the Internet.
14

Protein digestion, the protein requirement in nutrition, and food additives the contribution of Russell H. Chittenden.

Schelar, Virginia Mae, Chittenden, R. H. January 1900 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1969. / Vita. Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
15

Validação da metodologia de infravermelho com transformada de Fourier para identificação de adulteração em leite cru / Validation of the Fourier Transform Infrared spectroscopy to identify adulteration of raw milk

Laerte Dagher Cassoli 08 October 2010 (has links)
Objetivou-se avaliar a utilização da metodologia de infravermelho com transformada de Fourier (IVTF) na identificação de adulteração em leite cru. O objetivo no primeiro estudo foio de desenvolver calibração para identificação de adulteração através da comparação do espectro de leite adulterado com um espectro de referência para leite cru. Para construção do espectro referência foram coletadas 800 amostras de diferentes fazendas localizadas na região de estudo no período de agosto de 2009 a março de 2010. Através da análise de componentes principais, foram desenvolvidas oito calibrações com diferentes números de fatores (componentes principais). Para validação das diferentes calibrações, foram coletadas outras 100 amostras da mesma região de estudo. As amostras foram adulteradas com três diferentes adulterantes geralmente utilizados na adulteração do leite cru sendo eles: bicarbonato de sódio (BS), citrato de sódio (CS) e soro de queijo (SO). Para cada adulterante foram utilizadas três diferentes concentrações (BS: 0,05, 0,10 e 0,25 %; CS: 0,025, 0,050 e 0,075% e SO: 5, 10 e 20%). Para avaliação do desempenho das calibrações foram calculadas a especificidade e a sensibilidade para cada adulterante e respectivas concentrações. A especificidade foi de 92,9% na calibração com 12 fatores. Já a sensibilidade variou em função do adulterante, concentração e número de fatores. Todas as amostras adulteradas com bicarbonato foram identificadas corretamente com modelos de 10 fatores e na concentração mais baixa (0,05%). Já para o citrato, somente amostras com concentração de 0,075% foram identificadas em 93,9% dos casos para o modelo de 18 fatores. Amostras adulteradas com soro, mesmo na concentração mais alta (20%) puderam ser identificadas em menos de 47,1% dos casos, talvez pelo tratamento espectral realizado pelo software ASM em que parte do espectro não é considerado na construção das calibrações. A comparação espectral mostrou-se uma técnica interessante para identificação de leite adulterado e que também poderia antecipar a descoberta de novos adulterantes. Já no segundo estudo o objetivo foi desenvolver calibrações para determinação da concentração dos adulterantes bicarbonato de sódio, citrato de sódio e soro de queijo. Para desenvolvimento das calibrações foram utilizadas as amostras adulteradas do primeiro estudo e, para validação, foram coletadas outras 60 amostras que foram novamente adulteradas. O desempenho de cada calibração foi avaliado através da acurácia (Se), limite de detecção (LD) e coeficiente de determinação (R2). Todas as calibrações apresentaram R2 superior a 0,91 com LD de 0,015%, 0,017% e 3,9% para BS, CS e SO, respectivamente. Já a acurácia foi de 0,005%, 0,009 % e 2,26% para BS, CS e SO, respectivamente. Através dos resultados obtidos neste estudo, conclui-se que a metodologia de IVTF pode ser utilizada para determinação da concentração de bicarbonato de sódio, citrato de sódio e soro de queijo em leite cru. Associada à equipamentos automatizados, é uma opção viável no monitoramento destes adulterantes, tendo o baixo custo operacional e alto desempenho analítico como características adicionais. / The objective of this research was to evaluate the use of the methodology of Fourier Transform Infrared (FTIR) in identifying adulteration in raw milk. The objective of the first study was to develop scales to identify contamination by comparing the spectrum of adulterated milk with a reference spectrum for raw milk. To build the reference spectrum, 800 samples were collected from different farms located in the study area from August 2009 to March 2010. Through the analysis of principal components, eight scales with different numbers of factors (principal components) were developed. To validate the different calibrations, other 100 samples were collected from the same region of study. The samples were adulterated with three different adulterants commonly used in the adulteration of raw milk: sodium bicarbonate (SB), sodium citrate (SC) and whey (W). Each adulterant was used at three different concentrations (SB: 0.05, 0.10 and 0.25%; SC: 0.025, 0.050 and 0.075% and W: 5, 10 and 20%). To evaluate the performance of the calibrations, the specificity and sensitivity for each adulterant and its concentration were calculated. The specificity was 92.9% in the calibration with 12 factors. Sensitivity varied according to the adulterant, concentration and number of factors. All samples adulterated with bicarbonate were accurately identified in the 10-factor model and at the lowest concentration (0.05%). As for citrate, only samples at a concentration of 0.075% were identified in 93.9% of cases for the 18-factor model. Samples adulterated with whey, even at the highest concentration (20%) were identified in less than 47.1% of cases, which maybe attributed to the fact that part of the spectrum is not consideredin the spectral processing performed by ASM software. The spectral comparison proved to be an interesting technique for the identification of adulterated milk and that could also be used to discover new adulterants. In the second study, the aim was to develop calibrations for determining the concentration of sodium bicarbonate, sodium citrate and whey used as raw milk adulterants. To develop the calibrations, adulterated samples of the first study were used and, for validation, other 60 samples were collected and adulterated. The performance of each calibration was evaluated regarding accuracy (Se), detection limit (DL) and determination coefficient (R2). All calibrations presented R2 higher than 0.91 with DL of 0.015%, 0.017% and 3.9% for SB, SC and W, respectively. Accuracy was 0.005%, 0.009% and 2.26% for SB, SC and W, respectively. Results show that the FTIR methodology can be used for determining the concentration of sodium bicarbonate, sodium citrate and whey in raw milk. Associated with automated equipment, it is a feasible option for monitoring these adulterants, presenting low operational costs and high analytical performance as additional features.
16

Estudo de adulteração de queijos = espectrometria de massas por uma abordagem inovadora / Study of cheese adulteration : an innovative approach for mass spectrometry

Damario, Natália, 1988- 07 April 2014 (has links)
Orientador: Rodrigo Ramos Catharino / Texto em português e inglês / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-25T16:32:16Z (GMT). No. of bitstreams: 1 Damario_Natalia_M.pdf: 490227 bytes, checksum: 825e09295040a1c513eea757bb6936f0 (MD5) Previous issue date: 2014 / Resumo: O alto consumo global de queijos e a flutuação de disponibilidade e preço destes produtos lácteos os tornam alvos de fraudes. Uma das mais comuns é a adulteração de leites de alto valor agregado, como os de cabra e ovelha, com o então menos valioso leite de vaca, posteriormente vendido como matéria-prima para a indústria de queijo. Esta prática cria a necessidade de técnicas sensíveis para avaliar a autenticidade de queijos, incentivando o desenvolvimento e melhoria de métodos analíticos. Neste caminho, nós trazemos esta abordagem empregando a Direct Imprinting in Glass Surface Mass Spectrometry (DIGS-MS) para análise qualitativa de queijo em um instrumento MALDI. Esse método inclui uma preparação de amostra simples e eficaz além de rápida aquisição e interpretação de dados. A abordagem comprovou identificar prontamente lipídios de massas grandes em diferentes tipos de queijo, que podem ser associados a marcadores de qualidade. Também representa um potencial para controlar não só o produto final, mas também etapas produtivas, através da integração de dados estatísticos e analíticos, resultando em uma combinação poderosa para a discriminação de amostras com base no perfil lipídico. A ausência do efeito de matriz em toda cadeia analítica garante maior limpeza de sinal de espectros de massa e simplifica o processo / Abstract: High global consumption of cheeses and their availability and price fluctuations make these foodstuffs targets for frauds. One of the most common is the adulteration of highly priced milk (goat and sheep) with less valuable cow milk, which is sold as raw material for cheese industry. This creates the need for sensitive techniques to assess cheese authenticity by encouraging the development and improvement of analytical methods. In this path, we bring this approach employing Direct Imprinting in Glass Surface Mass Spectrometry (DIGS-MS) for qualitative cheese analysis in a MALDI instrument. This method includes simple and effective sample preparation and fast data acquisition and interpretation. It has proven to readily identify higher mass lipids in different types of cheese, which can be associated as quality markers. This can also represent potential to control not only the final product, but also productive stages, by integrating analytical and statistical data, resulting in a powerful combination for sample discrimination based on lipid profiles. The absence of matrix effect in the whole analytical chain ensures greater signal cleanliness of mass spectra and simplifies the process / Mestrado / Ciencias Biomedicas / Mestra em Ciências Médicas
17

Stanovení autenticity potravinářských výrobků s ovocnou složkou / Analysis of autenthicity of food products with fruit component

Prachárová, Adriana January 2021 (has links)
The aim of this thesis was to determine the authenticity of fruit food for infants using molecular and instrumental methods. In the experimental part, plant DNA isolations from fruit leaves (peaches, apricots, plums and apples) and bananas were performed. Further, DNA was isolated also from five commercial products, and from model mixtures that were prepared in terms of content identical to the commercial mixtures. The isolated DNA was characterized and verified by qPCR with plant DNA-specific ITS2 primers. Three triple primer pairs were selected, and their specificity was evaluated when performing multiplex PCR. This method makes it possible to detect more types of fruit in one reaction, reducing the economic and time requirements for detection. As none of the selected primer pairs were sufficiently specific for the apricot, the evidence from the plum and peach was further realized using duplex PCR. High resolution melting curve analysis was used for better DNA type recognition. Subsequently, agarose gel electrophoresis was performed to analyse the fragment lengths. Furthermore, experiments have been made to identify some specific phenolic substances in commercial and model fruit mixtures by HPLC. Since phenolic substances are degradable under unsuitable storage conditions, the presence of individual compounds was not detected by this method.
18

Geléia real: análises físico-químicas e químicas úteis para a caracterização e detecção da autenticidade ou adulteração do produto / Royal jelly: physico-chemical and chemical analyzes useful for the characterization and detection of authenticity or product adulteration

Garcia-Amoedo, Luis Henrique 02 June 1999 (has links)
A geléia real é um dos principais produtos da colméia que serve como alimento para as larvas em desenvolvimento, assim como para a abelha rainha por toda a sua vida. Tem sido utilizada pelas pessoas como um complemento alimentar devido às suas propriedades revitalizantes. O principal objetivo deste trabalho foi estabelecer as análises físico-químicas e químicas que poderão ser usadas para a caracterização da geléia real e detecção de sua autenticidade ou adulteração, enfatizando-se a determinação do ácido 10-hidroxi-trans-2-decenóico (10-HDA). A proposta do trabalho está justificada pela falta de legislação com relação a padrões de identidade e qualidade da geléia real e derivados. Foram determinados emalostras puras e adulteradas (com clara de ovo, água potável, iogurte natural, pasta de amido e uma mistura de leite condensado com própolis) os teores de umidade, cinzas, Iípides, proteínas, carboidratos, 10-HDA, pH, acidez titulável, reação com lugol e teste de solubilidade em meio alcalino. Como análises complementares foram determinados os teores das vitaminas B6 , A, pró-vitamina A (β-caroteno) e vitamina E nas amostras puras. Considerando-se os resultados obtidos preconizou-se as determinações de umidade, cinzas, lípides, proteínas, carboidratos, 10-HDA e teste de solubilidade em meio alcalino como os principais itens a serem observados. / Royal jelly is one of the most important products from beehive, which is used by growing up larves like food, and also for the queen bee for her entire life. It has being used by people as a complement because of the revitalizing properties. The main objective of this work was to establish the physicalchemical and chemical analysis, which could be used for characterization of the adulteration of royal jelly, mainly the 10-hidroxy-trans-2-decenoic acid (10-HDA). The purpose of this study is justified by the lack of legislation concerning the quality and identity standards of royal jelly and derivatives. There were determined in pure and adulterated samples (with condensed milk, water, yogurt, starch, egg white) the analysis of moisture, ash, lipids, proteins, carbohydrates, 10-HDA, pH, titrate acidity, iodine reaction, solubilíty test in alkaline solution. For complementary tests It was determined the values of vitamin B6 , A, provitamin A, and E in pure samples. Considering the obtained results it was suggested the use of moisture content, ash, lipids, proteins, carbohydrates, 10-HDA and solubility in alkaline solution, as the main items to be observed.
19

An evaluation of the use of menu risk assessment as a tool in food service protection programs

Gray, Lori A. 08 May 1997 (has links)
Despite the increase in information on the causes of foodborne disease, outbreaks continue to be a major preventable public health problem. Current food service establishment inspection programs, however, are not designed to assess the potential of risk for foodborne disease and do not focus prevention efforts where food service problems are more severe. The purpose of this study was, therefore, to first, compare mean inspection scores, mean number of critical violations, and mean risk index values for high risk, moderate risk and low risk food service establishments in Marion County, Oregon. Second, the study determined if menu risk assessment can be used to identify facilities that are considered to be "high risk" facilities. The data included most recent routine inspection results that had been previously collected by local sanitarians and data collected from a Menu Risk Assessment Survey which was developed by the Virginia Department of Health. The Menu Risk Assessment Survey was administered using a stratified random design, to 400 food service managers/owners between October 1993 and December 1993 The results showed that high risk establishments had lower mean inspection scores, higher mean number of critical violations, and a smaller mean risk index value than moderate or low risk establishments. The differences were attributed to lack of manager food safety education, menu items served, and operational practices observed in the establishment. The results also showed that there were statistically significant differences (p<.05) in the mean inspection score and the mean number of critical violations of "high risk" establishments and "low risk" establishments when responses to the Menu Risk Assessment Survey were compared. For example: 1) Establishments whose managers do not have food handler's training demonstrate more critical violations than establishments with trained managers, 2) Critical violations and lower inspection scores were more likely to occur in establishments that prepared and served potentially hazardous foods, 3) Food service establishments that handle extensive amounts of potentially hazardous food and serve larger populations were more likely to have lower inspection scores and increased numbers of critical violations. Based on the results found in this research, local health departments may find the Menu Risk Assessment Survey to be a useful tool in determining high, moderate, and low risk food service establishments to focus prevention efforts where the problems are more severe and are of greater public health risk. / Graduation date: 1997
20

Product quality modeling and control based on vision inspection with an application to baking processes

Zhang, Yingchuan 14 April 2005 (has links)
Manufacturing industries are facing major challenges in terms of improving product quality and increasing throughput while sustaining production costs to acceptable levels. Product-oriented processes, both legacy and new, are poorly monitored and controlled on the basis of distributed loop controllers that are aiming to maintain critical process variables within acceptable bounds. Thus, poor quality product results when such processes are subjected to large disturbances - operational failures, environmental changes, and changes in loading conditions. In this research, product quality modeling and control based on a vision inspection methodology is proposed to improve product quality and increase productivity. The main contributions of this research are twofold. First, this research introduces a product quality modeling methodology that combines both physical-based modeling and data-driven modeling. The quality model is the link between information coming from the inspection of product features and the specification of process control strategies. It is essential to control and optimize the process. Physical-based modeling is used to model the product temperature profile, and data-driven modeling is used to train the mapping from the product temperature profile to each quality metric. The break down of the sub models increase the flexibility of model development and reduce the effort to change the model when the quality metrics change. The second contribution is the development of a novel approach to control product quality based on vision inspection, which is developed as part of a hybrid, hierarchical architecture. The high-level control module involves scheduling of multiple plant processes, diagnostics of the failure condition in the process, and the supervision of the whole process. The mid-level control module, which is the focus of the work presented here, takes advantage of baking product quality indicators and oven parameter measurements to optimize zone temperature and conveyor speed set points so that the best product quality is achieved even in the presence of disturbances. The low-level control module consists of basic control loops. Each of them controls parameters of each operation in the process separately. They are generally simple and easy to implement.

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