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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.
161

Proposta para integrar os sistemas de gestão da qualidade, das boas práticas de fabricação e da APPCC em uma pequena empresa de sucos de frutas.

Carrizo, Alberto 05 December 2005 (has links)
Made available in DSpace on 2016-06-02T19:52:13Z (GMT). No. of bitstreams: 1 DissAC.pdf: 1825602 bytes, checksum: 66578e867a58642d29d296cfb15d5fc3 (MD5) Previous issue date: 2005-12-05 / The steady growth of the fruit juices sector is a significant factor strengthening the Brazilian economy; the richness of the tropical fruits, the quality of juices they are processed into and the luring presentation to consumers expanded the internal market and helped conquer demanding markets abroad. All this happened as a result of meeting stringent and assorted requirements, since food fruit juices included quality and safety are a must today. The purpose of this paper is to present a proposal to integrate management systems involving quality, good manufacturing practices and related legal requirements, as well as HACCP, in a small fruit juices company in the State of São Paulo. The proposal includes integrated cost-effective actions to implement the various standards. The research carried out concludes that the integration of management systems involving quality, good manufacturing practices and related legal requirements, as well as HACCP, is feasible. A relationship matrix of the respective requirements was designed during the research, which allowed conducting an initial joint and revealing assessment to evaluate the degree of fulfillment of those requirements. Bearing in mind the company´s scenario where the research was performed and the first application of this Integrated Management System took place, the proposal was not totally implemented. The necessity was perceived to test the Integrated Management System and monitor its operation in other food sector companies, thus not only evaluating the consistency of the proposal but also its flexibility to meet local specific requirements and detect improvement opportunities. / O crescimento do setor de produção de sucos de frutas vem contribuindo ao fortalecimento da economia brasileira; a rica variedade de frutas tropicais, a diversidade de formas de apresentação e a qualidade dos sucos ampliaram o mercado interno e conquistaram mercados externos, atendendo exigências cada vez mais rígidas. As empresas do setor estão submetidas a crescentes exigências de qualidade e segurança de seus produtos. O objetivo deste trabalho é apresentar uma proposta para integrar os sistemas de gestão da qualidade, das boas práticas de fabricação e requisitos legais correlatos, bem como da APPCC, em uma pequena empresa de sucos de frutas situada no interior do Estado de São Paulo, submetida às crescentes exigências dos clientes. A proposta inclui ações integradas contribuindo para racionalizar os recursos aplicados ao processo de adequação aos diferentes referenciais normativos. O trabalho conclui que é viável a integração dos sistemas de gestão da qualidade, das boas práticas de fabricação e requisitos legais correlatos e da APPCC. A matriz de correspondência entre requisitos respectivos, desenhada durante a pesquisa realizada, permitiu a avaliação conjunta do grau de atendimento dos mesmos, facilitando o processo de implementação a partir dos resultados obtidos. Tendo em vista o cenário da empresa em que foi desenvolvida a pesquisa e realizada a primeira aplicação da proposta do Sistema Integrado de Gestão, não foi possível implementar a proposta integralmente. Foi percebida a necessidade de testar sua implementação e operação em outras empresas do setor de alimentos, para avaliar não só a consistência da mesma, senão também sua flexibilidade para se ajustar às especificidades locais e detectar oportunidades de melhoria. Palavras-chave: qualidade do alimento, segurança do alimento, BPF, ISO 9001 (2000) e APPCC, Resolução ANVISA RDC 275/01, indústria de sucos, sistema integrado de gestão.
162

Food certification audits : a case study in the Western Cape

Valentine, Lucrecia Zinobia January 2008 (has links)
Thesis (MTech (Engineering))--Cape Peninsula University of Technology, 2008 / While there is a standard for quality and environmental auditors, there is no local or international standard for food safety auditing, which means auditors from different certification bodies can use their own discretion when auditing food establishments. There is a requirement to investigate the quality of work performed by South African food safety auditors. in order to establish whether they do in fact add value when conducting registration and certification audits. This is also an indication of the importance of improving and maintaining a high standard of food safety in the food services industry. The overall concept of food safety in South Africa IS clearly not defined. understood by only a few consumers, and not widely accepted. Research has shown that food retailers in South Africa in general do not believe food safety auditors are competent. In the wake of the Sudan Red scare two years ago. a long awaited food safety initiative was launched in February 2006. The scare pertaining to a carcinogenic food dye. which found its way into spices on local supermarket shelves, mobilized food industry role players to improve food safety standards. Under the auspices of the Consumer Goods Council of South Africa (CGCSA), the body responsible for establishing best practices and implementation standards, Food Safety South Africa (FSSA) will enable an organization to determine the exact nature and extent of possible and actual problems along the food supply chain. The key objectives of this research study are to determine whether one food certification standard is needed in South Africa and to assess the value added by the food auditors to their clients. Social research will be conducted within the ambit of the dissertation, with case study serving as research method. Both quantitative and qualitative research paradigms will be used to gather data for the research survey in support of the research question. forming the crux of the dissertation which reads as follow: "How can food safety auditors increase value added to the audit process in food environments in South Africa?"
163

Understanding the partitioning and concentration of trace elements in the plant organs of some food crops : influence of the plant allometry and of the growth stage / Compréhension de la répartition et de la concentration des éléments traces dans les organes de plantes cultivées pour l'alimentation : influence de l'allométrie et du stade de développement

Liñero Campo, Olaia 29 April 2016 (has links)
Le travail est axé sur l'accumulation d'éléments chimiques essentiels et non essentiels avec une attention particulière pour les parties des consommées, en lien avec la qualité sanitaire des produits alimentaires. Le travail de thèse est divisé en deux grandes parties. La première porte sur une expérimentation en plein champ où des plantes de blettes et de tomates ont été cultivées du stade plantules jusqu'à la maturité pendant 5 mois avec des pratiques agricoles conventionnelles ou biologiques. Les plantes ont été récoltées à 6 stades différents de croissance et nous avons déterminé la concentration des organes végétaux pour 27 éléments chimiques. L'objectif était d'étudier la répartition des éléments entre les organes en fonction de l'âge de la plante et des pratiques culturales.La seconde partie de la thèse a été consacrée à la compréhension et à la modélisation de la répartition du cadmium (Cd) chez le tournesol aux stades reproducteurs. Des plantes ont été cultivées du stade plantule jusqu'à la maturité, en solution nutritive avec une faible concentration en Cd cohérente avec les expositions aux champs. Durant la phase reproductive, cinq échantillonnages ont été effectués pour comprendre la répartition du Cd entre les organes ainsi que l'origine du Cd des graines (prélèvement racinaire versus remobilisation à partir d'autres organes). Au stade du bouton floral et pendant le remplissage des graines, le devenir du Cd récemment absorbé par les racines a été suivi et modélisé par traçage isotopique avec du 111Cd. Les rôles de la transpiration et de l'allométrie entre organes ont été plus particulièrement examinés. / This work is focuded on the accumulation of essential and non-essential elements, paying a special attention to the dible part of the plants, in terms of food safety and human health. The thesis work has been divided in two main parts. The first one is related to a field expeiment performed in open-air plots, where Swiss chards and tomato plants were grown from seedlings to maturity in a natural soil during five months, using organic or conventional agricultural practices. Plants were harvested at six different growth satges and the total concentrations of 27 elements were measured in all plants organs. The objective was to study the partitioning of elements between the plant organs, depending on the plant age on the cultivation practice. The second part of the thesis is devoted to the understanding and modelling of the partitioning of cadmium (Cd) in sunflowers at the reproductive stages. Sunflowers wre grown in nutrient solution at low Cd availability consistent with thaht found in the field, from germination toi maturity. During the reproductive period, five samplings were carried out to investigate the partitioning of the total Cd between plant organs and the origin of the Cd allocated to seeds (root uptake vs; remobilization from other plant organs). At the flower bud and grain filling stages, the partitioning of the Cd recently taken up between the different plant organs was followed and modelled by exposing several plants for the three days to a 111Cd enriched nutrient solution. The roles of the transpiration and of the plant allometry were specially investigated.
164

Análise de perigos e pontos críticos de controle no processamento de farinha de trigo integral / Hazard analysis and critical control points in the processing of whole wheat flour

Márcia Dimov Nogueira 21 August 2000 (has links)
O Sistema de Análise de Perigos e Pontos Críticos de Controle (APPCC) ou Hazard Analysis Critical Control Point (HACCP) é de grande importância para a Saúde Pública, quanto às doenças veiculadas por alimentos. O objetivo deste trabalho foi verificar a aplicabilidade do uso desse sistema na indústria de moagem de trigo, no processamento de farinha de trigo integral, produto com demanda crescente no mercado. Trinta produções de farinha foram coletadas numa indústria cuja capacidade de moagem é de 15ton./h na cidade de São Paulo. A população amostrada foi de 30 sub-amostras de trigo argentino (A) (12,8% de umidade média), 17 sub-amostras de trigo brasileiro (B) (13,1% de umidade média), 30 sub-amostras de trigo preparado para moagem (M) (15,6% de umidade média) e 30 sub-amostras de farinha de trigo integral (FTI), coletadas num período de 5 meses (de outubro de 97 à março de 98). A metodologia utilizada para pesquisa de sujidades leves foi a adotada pelos Métodos Oficiais da AOAC (1995). Houve modificações no método e um estudo foi realizado para conhecer sua performance. No isolamento de fungos foi utilizada a metodologia empregada pela AOAC/FDA Bacteriological Analytical manual (1992). Para identificação de fungos em relação ao gênero foi utilizado o método preconizado GELLI et al.(1990), SAMSON et al (1995), PITT and HOCKING (1997). Na análise de sujidades leves nos trigos foi evidenciada a contaminação por ácaros (A=90%, B=53%, M=77% e FTI=53%); no trigo argentino houve uma predominância para a família Tarsonemidae, enquanto que na respectiva farinha foi a família Acaridae. Alguns ácaros dessa última família estão implicados em reações alérgicas e estão sendo tratados como emergentes na segurança alimentar. Os insetos thisanópteros, os mais freqüentes nos trigos, foram eliminados na farinha de trigo integral. O percentual médio de contaminação fúngica dos grãos foi de A=99%, B=95% e M=94%. O principal gênero encontrado foi Aspergillus spp (A= 79,0%, B= 39,3% e M= 64,2%). O menos freqüente Fusarium spp (A= 2,9%, B= 2,7% e M=1,5%). Na farinha de trigo integral o principal gênero encontrado foi o Penicillium spp e o Fusarium não foi isolado. O desoxinivalenol foi encontrado em uma amostra de farinha de trigo integral a uma concentração de 231 ng/g. O sistema APPCC se aplica aos moinhos e os auxilia a controlar suas produções do ponto de vista da segurança alimentar. / Food safety is a major concern facing the food industry today. Hazard Analysis Critical Control Point (HACCP) provides a structured approach to the assurance of safety of products. The aim of this study was to verify the use of HACCP system in a milling industry, precisely in the whole wheat flour production. At first step two hazards were analyzed: deoxynivalenol and allergenic mites in whole wheat flour Thirty (30) lots of flour were collected in an industry which capacity was 15 ton./h in São Paulo city. Those lots had 30 sub-samples of argentine (A) wheat (12,8% average moisture content), 17 sub-samples of brazilian (B) wheat (13,1% m.c.), 30 sub-samples of wheat for milling (M) (15,6% m.c), and 30 sub-samples of whole wheat flour (FTI) that were analyzed in a five months period (from 97/october to 98/march). Light filth was isolated from grains and flour, according to Official Methods of AOAC International. Methodology of extraction of light filth from whole wheat flour was studied to know the repeatability according to AOAC methods. Fungi isolation was performed according to AOAC/FDA Bacteriological Analytical Manual (1992) methodology; genera were identified according GELLI et al.(1990), SAMSON et al (1995), and PITI and HOCKING (1997). Detection and quantification of deoxynivalenol (DON) were done by thin layer chromatography (TLC) according to SABINO et al. (1989).The most significant light filth contamination in wheat were mites (A= 90%, B= 53%, M= 77% e FTI= 57%), argentine wheat had as a predominant mite the family Tarsonemidae and flour had Acaridae. The average fungal contamination in grains was 99%, 95% e 94% in argentine, brazilian and wheat for milling respectively. The predominant genera was Aspergillus spp ( A= 79,0, B=39,3% e M= 64,2 %), and Fusarium was the least frequent in wheat (A>/b>=2,7%, B= 2,8% e M=1,5%). Only one lot of whole wheat flour was contaminated by DON at level 231 ng/g. This study showed that HACCP system is appropriated for control hazards in milling industry. However, DON should be controlled before wheat get into industry, and this control need to be registered. Mites are new emergentes to cause allergy by ingestion and have to be controlled by GMP procedures.
165

Estabilidade oxidativa da carne de frangos alimentados com diferentes fontes lipídicas, armazenada sob congelamento. / Oxidative stability of chicken thigh from broilers fed with different fat sources stored under freezing.

Lilian Marques Pino 04 March 2005 (has links)
Este estudo teve como objetivo caracterizar química e fisicamente a carne de sobrecoxas de frangos alimentados com diferentes fontes lipídicas (óleo de soja - OS, óleo ácido de soja - AC e óleo de vísceras de frangos - FR) e a mistura destas (25% óleo de soja + 75% óleo ácido de soja – OS25AC75, 50% óleo de soja + 50% óleo ácido de soja – OS50AC50, 50% óleo de soja + 50% óleo de vísceras de frangos – OS50FR50) e estudar a estabilidade oxidativa das sobrecoxas, durante nove meses de armazenamento sob congelamento a -18ºC. Foram determinadas a composição centesimal, o perfil de ácidos graxos, pH e cor para a caracterização e valor de TBARS para o acompanhamento da estabilidade oxidativa das sobrecoxas de frangos. A umidade e o teor de proteína bruta variaram de 68 a 70% e 16,33 a 18,19%, respectivamente, encontrando-se dentro da faixa de valores citados pela literatura. Os teores de óleo de 11,0 a 11,72% foram superiores aos encontrados na literatura, o que provavelmente se deve a diferenças de raça dos animais, idade de abate e tipo de alimentação. Ao longo do experimento os valores de pH variaram de 5,88 a 6,39, sendo que apenas o tratamento OS25AC75 foi influenciado pelo tempo de armazenamento. A cor também se alterou em todos os tratamentos com o tempo. O perfil de ácidos graxos da fração lipídica da carne de sobrecoxa dos animais submetidos aos tratamentos estudados está de acordo com a literatura, sendo que a carne dos animais alimentados com a dieta adicionada de óleo ácido de soja apresentou uma quantidade de ácidos graxos insaturados inferior aos demais tratamentos. Os valores médios de TBARS variaram de 0,21 a 0,90 mg de malonaldeído/kg, ao longo do experimento. A carne de frangos alimentados com OS50FR50 foi a que apresentou a menor estabilidade, ainda mais significativa no final do estudo, o que foi confirmado através da intensidade do odor de ranço, durante a análise sensorial. De forma geral, o armazenamento afetou a qualidade da fração lipídica da carne de sobrecoxas de frangos. / This work had the objective to characterize chemically and physically the meat of chicken thighs, fed with different lipid sources (soy oil, acid soy oil and chicken offal oil) and the mixture of these (25% soy oil + 75% acid soy oil – OS25AC75, 50% soy oil + 50% acid soy oil – OS50AC50, 50% soy oil + 50% chicken oil – OS50FR50) and to evaluate the oxidative stability of the meat, during nine months of frozen storage, under -18ºC. Bromatological and fatty acid composition, pH and color determinations were performed for the chemical and physical evaluation, as well TBARS value for the chicken thigh oxidative stability monitoring. The moisture and the crude protein values ranged from 68 to 70% and from 16.33 to 18.19% respectively, within the range of values found in the literature. The fats contents from 11.0 to 11.72 % were higher than those found in the literature, which probably is justified by the differences in animal breed, age of slaughtering and type of feeding. Along the experiment, the values of pH varied from 5.88 to 6.39%, however only OS25AC75 was influenced by the time. The color was affected by storage in all treatments. The fatty acid content of lipid fraction of the thigh chicken meat was in accordance whith the literature, the chicken meat of animals fed with diet added of acid soy oil presented a least unsatturated fat acid of the all treatments. The average TBARS values varied from 0.21 to 0.90 mg malonaldehyde/kg. The thigh meat from broilers fed OS50FR50 was the one that presented the least stability, even more significant at the end of the experiment wich was confirmed with intensity rancidity flavor detected by the sensory analysis. In general the time of storage affected the oxidative quality of the lipid fraction.
166

Qualidade do mexilhão Perna perna submetido ao processo combinado de cocção, congelamento e armazenamento / The quality of the mussel (Perna perna) processing by cooking, freezing and storage

Daniela Cordeiro 02 September 2005 (has links)
Os mexilhões cultivados no litoral Norte de São Paulo, município de Ubatuba, são comercializados in natura, constituindo risco à população. Com o crescimento da atividade é possível sugerir a implantação de uma unidade de processamento de mexilhões que promova um aumento do tempo de armazenamento, facilitando a comercialização e permitindo a exportação, além de fornecer ao consumidor um produto de melhor qualidade. Os mexilhões foram submetidos ao processamento por cocção, congelamento e armazenamento, sendo então determinados o ponto de congelamento, a velocidade de congelamento a as curvas de congelamento do mexilhão semidesconchado. A qualidade microbiológica e físico-química do produto foi avaliada. O beneficiamento do mexilhão iniciou-se com a cocção por imersão em água à ebulição por 10 minutos. Após a retirada das conchas, os mexilhões foram congelados individualmente IQF (Individually Quick Frozen) a –20ºC e armazenados a -18ºC durante 90 dias. A curva de congelamento do mexilhão apresentou forma geral típica, com o ponto de congelamento situando-se na faixa de zero a –1,5ºC; a velocidade de congelamento variou de 2 cm/h a 3,3 cm/h, conforme a disposição dentro da câmara de congelamento. Os resultados físico-químicos mostraram que não houve diferença significativa no valor nutricional dos mexilhões in natura, processados e armazenados, apresentando os teores médios de 7,4mg/100g de proteínas, 5,8 mg/100g de carboidratos e 1,4 mg/100g de lipídeos. Os valores encontrados para BNVT, TMA e pH no mexilhão in natura foram, 4,3 mg/100g; 2,0 mg/100g e 6,2, respectivamente, estando dentro dos limites estipulados pela legislação de 30mg/100g para BNVT e 4 mg/100g de TMA. Após o processo de cocção e congelamento houve um aumento no valor do pH para 6,9, enquanto o BNVT manteve-se na média. Todas as amostras de mexilhão in natura atenderam aos padrões microbiológicos estabelecidos pela legislação (RDC, nº12 de 02 de janeiro de 2001). Salmonella sp e Vibrio parahaemolyticus não foram isoladas em nenhuma das amostras de mexilhões in natura, cozidos, congelados e armazenados. O tratamento térmico foi efetivo no controle dos coliformes fecais, redução de coliformes totais, Staphylococcus coagulase+ e psicrotróficos. O processo de congelamento reduziu a contagem de coliformes totais e Staphyloocccus coagulase+, mantendo-se inalterados durante o armazenamento a –18ºC por 90 dias. Concluiu-se que o beneficiamento do mexilhão pelo processo combinado de cocção, congelamento e armazenamento assegura a qualidade físico-química e microbiológica do produto, podendo ser adotado como padrão para industrialização. / The mussels cultivated in the coast North of São Paulo, city of Ubatuba, are commercialized in natura, constituting risk to the population. With the growth of the activity it is possible to suggest the implantation of a unit of mussel processing that promotes an increase of the storage time, facilitating the commercialization and allowing the exportation, besides supplying to the consumer a product of better quality. The mussels had been submitted to the processing for cooking, freezing and storage, being then determined the freezing point, the speed of freezing to the curves of freezing of the semidesconchado mussel. The microbiological quality and physicochemical of the product were evaluated. The processing of the mussel was started with the immersion in boiling water per 10 minutes. After the withdrawal of the shells, the mussels had been frozen individually IQF (Individually Quick Frozen) at -20ºC and stored at -18ºC during 90 days. The curve of freezing of the mussel presented typical general form, with the freezing point placing from zero to -1,5ºC; the freezing speed varied from 2 cm.h-1 to 3,3 cm.h-1, as the disposal
167

Bottom-up gesteuerte Anpassungen von Daphnia galeata an die Nahrungsbedingungen in der biomanipulierten Talsperre Bautzen

Voigt, Hanno 05 April 2002 (has links)
Ziel der Arbeit war eine möglichst umfassende Analyse der Nahrungsbedingungen von D. galeata unter Berücksichtigung der damit verbundenen Strategien der Daphnien zur Optimierung des Nahrungserwerbs, um den Einfluß dieser Faktoren bezüglich des Auftretens einer Sommerdepression der Daphnien zu beurteilen. Aufbauend auf den bereits vorhandenen Kenntnissen aus der Literatur sollte dazu im Rahmen der Arbeit festgestellt werden, ob morphologische Veränderungen des Filtrationsapparates der Daphnien (Ausbildung großer, hydrodynamisch dichter Filter), die als Reaktion auf die geringen Nahrungsmengen im Klarwasserstadium auftreten, bei einer drastischen Erhöhung der Nahrungskonzentration zu einer "Überlastung" der Filterbeine der Daphnien, zu hohen Energieausgaben und schließlich zu erhöhter Mortalität (Sommerdepression) führen können. Hauptziel war dabei die Klärung der Frage, ob bottom-up gesteuerte schnelle Veränderungen im Nahrungsangebot, wie sie für geringe bottom-up Limitation (Hypertrophie) typisch sind, eine erhöhte Mortalität bei Daphnien hervorrufen können. Die Beantwortung dieser Fragestellung ist wichtig, um die Effizienz der top-down Steuerung (Biomanipulation) als ökotechnologische Maßnahme zur Gewässersanierung zu erhöhen. Dazu wurden in der biomanipulierten Talsperre Bautzen in drei Untersuchungsjahren (1997 - 1999) wichtige bottom-up wirkende Steuerfaktoren der Daphnienentwicklung sowie morphologische Charakteristika der Filterkämme und physiologische Leistungskriterien von D. galeata vor und während der Zeit des potentiellen Auftretens einer Sommerdepression untersucht. Aus den Ergebnissen ließ sich ableiten, daß das Zusammenspiel der vielfältigen Anpassungsmöglichkeiten der Daphnien in einem bestimmten Variationsbereich der Steuerfaktoren eine erfolgreiche Strategie zur Optimierung der Nahrungsaufnahme darstellen kann. Werden jedoch bestimmte Schwellenwerte über- oder unterschritten, ist eine Kompensation durch die Anpassungsstrategien nicht oder nur bedingt möglich. Dabei kann durch verschiedene Ursachen der gleiche Effekt (Mortalität adulter Daphnien) auftreten, was die Interpretation erschwert. Dieser Effekt wird besonders bei adulten Daphnien durch die gegenüber juvenilen Daphnien höheren Filterwiderstände und die damit verringerte effektive Energieaufnahme begünstigt. Erst wenn ungünstige Nahrungsbedingungen und die am Ende der Klarwasserphase beobachteten ungünstigen Konstellationen der Filterkämme zusammentreffen (timing), tritt die erhöhte Mortalität adulter Daphnien auf. Die Ergebnisse der Untersuchungen unterstreichen damit die Bedeutung von Ganzsee-Experimenten und die möglichst simultane Erfassung verschiedener Zustandsgrößen, um eine umfassende Kausalanalyse der Sommerdepression der Daphnien zu ermöglichen, zu der die vorliegende Arbeit einen Beitrag liefert. Für den Erfolg der Biomanipulation konnte daher geschlußfolgert werden, daß eine nachhaltige Wirkung nur dann erreicht werden kann, wenn zusätzlich zur top-down Steuerung des Nahrungsnetzes gleichzeitig eine erfolgreiche Kontrolle der bottom-up Prozesse im Gewässer realisiert wird, indem starke Schwankungen von bottom-up Faktoren vermieden werden und damit das System insgesamt stabilisiert wird. / The occurrence of midsummer declines of daphnids is often related to poor food conditions or fish predation. In this three-year-study on the midsummer decline of Daphnia galeata field investigations in the highly eutrophic biomanipulated Bautzen reservoir were combined with flow-through experiments in the laboratory. The following hypothesis was tested: The inability of adult Daphnia to reduce the filtering area of their feeding appendages in response to fast increasing food levels after a clear-water phase enhances adult mortality. During the clear-water phase daphnids develop large and dense filtercombs to optimise their filter feeding. When food concentrations increase, however, this adaptation to low-food situation may be inappropriate due to too high energy consumtion. As adult daphnids cannot reduce the size of their feeding appendages, the filtration process may be hindered when seston concentrations rise, resulting in reduced fitness and increasing adult mortality. Indeed, adult survival in the laboratory (predation excluded) drastically decreased exactly at that time when the Daphnia galeata population in Bautzen reservoir declined. However, enhanced mortality was found irrespective of different food conditions offered during the experiments. It is concluded that increased mortality of adult daphnids is not an direct effect of their inability to adapt the morphology of their filtercombs to high seston concentrations. Furthermore daphnids are able to compensate unfavorable food conditions within a certain range by different kinds of adaptation mechanisms. Therefore the timing of the changes of food conditions and the adaptations of daphnids is most important to the efficiency of energy gain of the daphnids. Concerning the success of biomanipulation it is concluded that in addition to the regulation of top-down mechanisms there is an urgent need for control of bottom-up processes in order to stabilize the ecosystem.
168

Hodnocení kvality bezlepkových potravin se zaměřením na pečivo / Quality assessment of gluten-free foods with a focus on pastries

ZIMMELOVÁ, Helena January 2019 (has links)
The topic of this thesis is the production of gluten-free bread from naturally gluten-free flour, which will be enriched with suitable additives that will increase antioxidant activity and naturally effect on the structure of the pastry, so it will meet the sensory requirements of final consumers. The literary part define, which proteins can be found in cereals, what does the gluten means, its function in the pastry and which diseases can cause. In connection with these diseases, a gluten-free diet for improving the patient's health and suitable foodstuff are briefly described. The literary part is concluded with the theory of sensory evaluation. The practical part deals with the production of naturally gluten-free breads enriched with ingredients from kitchen onions (Allium cepa L.) and subsequent sensory evaluation of this bread. Selected statistical procedures were used to obtain, processed and evaluated data. Antioxidant activity was also monitored and evaluated. By using texture-meter was find out, what effect has additives on aging of gluten-free bread.
169

Proposta e avaliação de uma sistemática para a implementação da norma ISO 22000: 2005 - sistemas de gestão da segurança de alimentos e exemplo prático de sua implementação / Proposed and evaluation of a system for the implementation of ISO 22000: 2005 - Food safety management systems and practical example of its implementation

Lopes, Ellen Almeida 18 December 2007 (has links)
Foi desenvolvida uma proposta de sistemática para implementação de Sistema de Gestão da Segurança de Alimentos com base na Norma ISO 22000:2005 (NBR ISO 22000:2006). Esta sistemática está composta por: A) Mapeamento da documentação; B) Formulários para o Planejamento do sistema APPCC/ HACCP com base na norma ISO 22000, bem como Instrução para seu uso, incluindo tanto as etapas preliminares como os 7 Princípios estabelecidos pelo Codex Alimentarius; C) Documentos para a verificação dos sistemas: Checklist para auditoria de verificação, tanto de adequação como de implementação, e Mapeamento da comunicação. Esta sistemática foi aplicada em uma linha de produtos em pó de empresa real, de porte médio, denominada, ficticiamente, empresa EXEMPLO. Foram dados os treinamentos necessários, adequados ao nível de conhecimento da equipe de segurança de alimentos, e realizadas reuniões de consultoria. Após implementação da sistemática proposta pela equipe da empresa EXEMPLO na linha de produtos escolhida para este fim, foi realizada uma auditoria de verificação para a avaliação da adequação do Sistema de Gestão da Segurança de Alimentos com base na Norma ISO 22000. A equipe foi composta por três auditores, sendo dois deles com formação nível auditor líder de ISO 22000. Concluiu-se que a sistemática é eficaz e adequada, atendendo plenamente às exigências da Norma ISO 22000. Foi, também, incluído no trabalho exemplo prático da documentação básica resultante da implementação na empresa EXEMPLO. A sistemática e modelos desenvolvidos, bem como a visualização de um exemplo prático, podem auxiliar as empresas a diminuir significativamente o tempo de implementação, embora ajustes devam ser feitos para adequação à sua realidade. Os ajustes necessários devem considerar os requisitos regulamentares, dependendo do tipo de produto e do órgão regulatório responsável pela sua regulamentação e fiscalização, bem como requisitos estatutários que possam impactar na sistemática desenvolvida. / A proposed methodology was developed for the implementation of a Food safety management system based on ISO 22000:2005 (NBR ISO 22000:2006). This methodology includes: A) Map of all necessary documents; B) Forms for the HACCP system planning, based on ISO 22000 plus related instruction on how to use these forms, including the preliminary steps and the 7 Principles established by Codex Alimentarius; C) Documents for ISO 22000 system verification: Checklist for system assessment, considering adequacy and implementation and a Map of communication activities. This methodology was applied to one organization of medium size, focusing on one of its product lines. This organization was identified as EXAMPLE Organization. Necessary trainings and consultancy were offered by the author, considering the knowledge level of the food safety team. After implementation was complemented by the EXAMPLE Organization, according to the organization, an assessment was performed by a team composed of 3 auditors, two of them at the ISO 22000 lead auditor level. The main objective of this audit was to evaluate the adequacy of the proposed methodology. The conclusion was that the methodology is effective and adequate to the requirements of the ISO 22000 standard. The main documentation developed was also shown as the result of the implementation. The methodology and forms developed may help organizations to reduce the time involved in the implementation of the ISO 22000 system, even though adjustments to their circumstances shall be made. The necessary adjustments shall consider the kind of the product and the related statutory and regulatory requirements.
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Dimensions of the dining experience of academic employees at full-service restaurants

Naude, Petro 09 1900 (has links)
Full-service restaurants serve many different types of customers with preconceived ideas about what they want and expect to receive from the restaurant. During the dining experience, each customer experiences the service differently and subconsciously evaluates the experience differently. The purpose of this study is to determine the expectations and perceptions of customers regarding the dining experience dimensions at Full-Service Restaurants (FSRs). The dimensions relate to service quality, food quality and ambience quality expectations and perceptions of customers. Customer satisfaction was also analysed, as a satisfied customer will show return intentions and this customer will tell friends and family about this FSR. A self-administered survey of employees at a tertiary academic institution revealed that waiter professionalism, value for money and the atmosphere in the restaurant are the most important considerations when it comes to the expectations of the dining experience. The findings of this study presented a demographic profile (gender, age, home language, highest education qualification, LSM) and it was found that demographic category groups differ in the way that they perceive the dining experience. The study reveals that males tends to be less critical than women, LSM 9 respondents are less critical than LSM 10 respondents and respondents with an undergraduate degree or less are less critical than respondents with a post-graduate degree. Respondents were satisfied overall with their dining experiences. Recommendations include that management must focus on pricing strategies, waiter training and the flow of communication between the restaurant and the customer. The recommendations made in this study will assist management of FSRs to understand the significance of the dining experience dimensions and to implement the required levels of service, food and ambience quality. With this knowledge, the management of FSRs can be assured of a satisfied customer and a competitive offering. / Business Management / M. Com. (Business Management)

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