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Qualidade de méis comercializados nas feiras-livres e mercados públicos da cidade do Recife, PEROLIM, Maria Betânia de Queiroz 20 August 2013 (has links)
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Previous issue date: 2013-08-20 / In this work the purpose was to investigate the quality of honey marketed in popular markets of the City of Recife, Pernambuco. On total, 55 honey samples were submitted to carbon isotopic evaluation, microbiological and physicochemical tests, for, respectively, detect adulteration with corn sugar and cane sugar; identify coliforms 35°C and 45°C, mold and yeasts; and determine indexes of moisture, hydroxymethylfurfural, ash, reducing sugars, apparent sucrose, water insoluble solids, diastase activity and acidity. The results revealed that 31 (56,36%) samples were adulterated with sugars, 46 (83,64%) honeys were contaminated with molds and yeasts and 53 (96,36%) indicated physicochemical parameters unconforming with the Technical Regulation of Identity and Quality of Honey. Pure and adulterated honeys with C4 source, contaminated by fungi and / or physicochemically compromised, are marketed at the popular markets, in City of the Recife. Its ingestion may harm the consumer by risk acquire products unfit for consumption, with nutritional depreciation and microbial contamination. / Neste trabalho o objetivo foi pesquisar a qualidade de méis comercializados nas feiras-livres e mercados públicos da Cidade do Recife, Pernambuco. Ao total, 55 amostras de mel foram submetidas à análise isotópica do carbono, testes microbiológicos e ensaios físico-químicos, a fim de, respectivamente, detectar adulteração com açúcares provenientes do milho ou cana-de-açúcar; identificar coliformes 35°C, coliformes 45°C, bolores e leveduras; e determinar os índices de umidade, hidroximetilfurfural, cinzas, açúcares redutores, sacarose aparente, sólidos insolúveis em água, atividade diastásica e acidez. Os resultados revelaram que 31 (56,36%) amostras estavam adulteradas com açúcares, 46 (83,64%) apresentaram contaminação com bolores e leveduras e 53 (96,36%) indicaram parâmetros físico-químicos em desacordo com o Regulamento Técnico de Identidade e Qualidade do Mel. Méis puros e adulterados com açúcares provenientes de fontes C4, contaminados por fungos e / ou comprometidos físico-quimicamente, são comercializados nas feiras-livres e mercados-públicos, distribuídos na Cidade do Recife. Sua ingestão pode causar prejuízos à população consumidora pelo risco de pessoas adquirirem produtos impróprios ao consumo, com depreciação nutricional e / ou contaminação microbiana.
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Sistema de monitoramento em tempo real de destilações de petroleo e derivados empregando a espectroscopia no infravermelho proximo / System of monitoration in real time of destillations of petroleum and derived using the near infrared spectroscopyScafi, Sergio Henrique Frasson 20 December 2005 (has links)
Orientador: Celio Pasquini / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Quimica / Made available in DSpace on 2018-08-06T01:49:47Z (GMT). No. of bitstreams: 1
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Previous issue date: 2005 / Doutorado / Quimica Analitica / Doutor em Ciências
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Características quantitativas e qualitativas da proteína do leite produzido na região sudeste / Quantitative and qualitative characteristics of milk protein produced in Southeast regionLuiz Carlos Roma Junior 22 February 2008 (has links)
A maior valorização da proteína dentre todos os constituintes do leite foi o foco do presente estudo. Foi abordado a variação e fraude no teor de proteína e também o aspecto de qualidade da proteína produzida em propriedades leiteiras. Todos os experimentos foram realizados durante o período de outubro de 2005 a julho de 2007, em propriedades leiteiras da região sudeste, bem como, ensaios laboratoriais para estudo de fraudes em Piracicaba, SP. A variação do teor proteína e outros componentes do leite, foi acompanhada pela avaliação das condições climáticas encontrando influência significativa sobre a qualidade do leite. Com isso pôde ser observado que a época de outono destacou-se como mais vantajosa para produção de leite, atingindo bonificação de até 8,5% dentro de um programa de pagamento por qualidade. Sendo que, a contagem de células somáticas foi o item que mais colaborou com a penalização dos produtores. Assim, o efeito da contagem de células somáticas e da época do ano, deveriam ser contemplados dentro das tabelas de pagamento por qualidade. O segundo aspecto estudado foi a qualidade da proteína, mais especificamente Proteína Instável. A Proteína Instável seria o leite com coagulação na prova do álcool, sem relação alguma com acidez elevada, mastite ou alta contagem bacteriana. Para este estudo, foram acompanhadas propriedades leiteiras para a quantificação do problema de proteína instável e a identificação dos fatores relacionados com sua ocorrência. Como resultado, foi identificada uma ocorrência de 7% do volume total de leite produzido ao longo de um ano, com concentração maior dos casos no período de início de outono e final de inverno. Como fatores ligados a ocorrência, identificou-se o estágio de lactação avançado e diminuição do escore de condição corporal dos animais. Esta relação dos fatores está ligada à queda significativa da lactose no leite explicado pelo baixo teor energético da dieta, ou baixo consumo de matéria seca. Como último aspecto estudado, a influência da fraude no teor de proteína sobre a qualidade do leite e a detecção através de equipamentos automatizados. Foram utilizados como agentes de fraude: soro de leite, urina bovina e uréia pecuária. Todos os tipos de fraude alteraram significativamente a qualidade do leite. Estas alterações podem ser detectadas através dos equipamentos automatizados para análise do leite. Com isso, a detecção da fraude por estes equipamentos é possível através de análise conjunta de alguns componentes do leite. A abrangência do presente estudo nos três aspectos expostos, contribui com a importância da busca por qualidade da matéria-prima dentro dos programas de pagamento, principalmente para o componente proteína. / A higher valorization of the protein amongst all the milk components is the focus of the present study. The variation and the adulteration in the protein content have been studied as much as the aspect of quality of the protein produced in milk facilities. All the experiments have been carried through during the period between October 2005 and July 2007, at dairy properties in the Brazilian Southeastern region, and the laboratorial assays for study of adulterations have been performed in Piracicaba, SP. The variation of the content protein and other components of milk was followed by the evaluation of the climatic conditions and it has been considered as of a significant influence in the milk quality. Thus, it could be observed that the autumn season has been considered the most advantageous one for milk production reaching an additional benefit of up to 8,5% of a program for payment related to quality. The somatic cells count has been the item that has influenced the most with the penalization of the producers. Thus, the effect of the somatic cells count and the season should be contemplated when analyzing the tables of payment related to quality. The second studied aspect there is the protein quality, more specifically the Unstable Protein. The Unstable Protein should be the milk with coagulation in the test of the alcohol, without any relations concerning elevated acidity, mastitis or high bacterial count. For this study, milk farms have been observed for the quantification of the Unstable Protein problem and the identification of the factors related to its occurrence. As a result, an occurrence of 7% of the total volume of the produced milk throughout one year has been identified, with higher concentration of the cases in the months of the beginning of autumn and of the end of winter. As related factors to the occurrence, it has been identified the advanced period of lactation and reduction of the score of the corporal condition of the animals. This relation of the factors is linked to the lactose decreasing in the milk which is explained by the low energy content into the nourishment or low consumption of dry substance. As the last studied aspect was the influence of the adulteration in the protein content on the quality of milk and its detection through computerized equipment. As adulteration agents the following items have been considered: whey milk, bovine urine and urea. All kinds of adulteration have significantly modified the quality of milk. These alterations can be detected through the computerized equipment for milk analysis. Thus, the detection of the adulteration through this equipment is possible through the joint analysis of some of the milk components. The comprehension of the present study in the three observed aspects contributes to the research importance for quality of the raw material in the payment programs, mainly for the component protein.
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Influência da adulteração de combustíveis no desempenho e na vida útil de motores de combustão interna de ignição por faísca de pequeno porte utilizados em motocicletas. / Influence of fuels adulterations in performance and useful life for internal combustion engine by spark ignition of low volumetric displacement for motorcycles.Luiz Vicente Figueira de Mello Filho 03 March 2009 (has links)
Este trabalho tem como principal objetivo mostrar os efeitos do uso de gasolina adulterada em motores de pequena cilindrada em seus desempenhos e durabilidades. Para tanto, foram realizados ensaios comparativos em três motores carburados de aplicação em motocicletas, de mesmas séries. Estes motores consumiram gasolina C, padrão brasileiro de combustível para motores de ignição por faísca, e misturas desta gasolina com etanol hidratado carburante e solvente C-9. Os resultados mostram alterações de desempenho, nas concentrações de gases poluentes produzidos e nos níveis de deterioração. / This work has as main aim to show the effects of the use of the out of specification fuels in performance and durability of the low volumetric displacement engines. So, it was carried out comparative tests in three similar engines, equipped with carburetors as fuel metering arrangement, applied in motorcycles. These engines worked with standard gasoline C, Brazilian reference fuel to spark ignition engines and blends containing hydrated ethanol and C-9 solvent. The results show changes in performance, in the pollutant gases concentration productions and deterioration levels.
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Estudo de adulteração de queijos = espectrometria de massas por uma abordagem inovadora / Study of cheese adulteration : an innovative approach for mass spectrometryDamario, 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
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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
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Stanovení autenticity potravinářských výrobků s ovocnou složkou / Analysis of autenthicity of food products with fruit componentPrachárová, 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.
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Determinantes da adulteraÃÃo dos combustÃveis / Determinants tampering fuelCarlos Brasil Gouveia 08 February 2012 (has links)
nÃo hà / This work contributes to a better understanding of the phenomenon of adulteration of fuel, in
order to identify possible economic determinants related to this practice. With the objective of
a complete description of the problem, there is the need to preliminarily study the oil industry,
which was done transpiring succinctly, from the birth of the oil industry to the current stage of
it, featuring and highlighting its most important aspects for the economy. Then it approaches
the question of asymmetric information present in the fuel retail markets, and finally through
the construction of econometric models that take into account assumptions formalized in
works related to the problem of adulteration of fuel, then the evidence to economic
determinants. / Este trabalho contribui para um melhor entendimento do fenÃmeno da adulteraÃÃo de
combustÃveis, visando à identificaÃÃo de possÃveis determinantes econÃmicos, relacionados a
tal prÃtica. Tendo por objetivo uma perfeita caracterizaÃÃo do problema, verifica-se,
preliminarmente, a necessidade de estudar o setor petrolÃfero, e assim foi feito transcorrendo
de maneira sucinta, do nascimento da indÃstria do petrÃleo ao atual estÃgio da mesma,
caracterizando e ressaltando seus aspectos mais importantes para a economia. Posteriormente,
aborda-se a questÃo da assimetria de informaÃÃes presente nos mercados varejistas de
combustÃveis, e, finalmente, atravÃs da construÃÃo de modelos economÃtricos que levem em
conta pressupostos formalizados nos trabalhos relacionados ao problema da adulteraÃÃo de
combustÃveis, evidenciando-se entÃo os determinantes econÃmicos.
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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 adulterationGarcia-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.
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An evaluation of the use of menu risk assessment as a tool in food service protection programsGray, 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
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Product quality modeling and control based on vision inspection with an application to baking processesZhang, 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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