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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.
71

Dietary modulation of the human colonic microbiota through plant-derived prebiotic compounds

Kassim, Muhammad Arshad January 2007 (has links)
Thesis (M.Tech.: Biotechnology)- Dept. of Biotechnology, Durban University of Technology, 2007 xv, 127 leaves / The human gut microbiota play a major role in host health, and attempts are being made to manipulate the composition of the gut microbiota-increase the composition of bacterial groups, such as lactobacilli and bifidobacteria that are perceived as exerting health promoting properties. These bacteria defined as food supplements (probiotics) beneficially affect the host by improving the intestinal microbial balance, and have been used to change the composition of the colonic microbiota. However, such changes may be transient, and the implantation of exogenous bacteria therefore becomes limited. In contrast, prebiotics are naturally occurring carbohydrates that are classified as non-digestible oligosaccharides present in edible plants. These carbohydrates enter the colon as intact compounds, elicit systemic physiological functions and act as fermentable substrates for colonic microflora-influencing the species composition and metabolic characteristics of intestinal microflora providing important health attributes. Currently, a widely marketed prebiotic, inulin is extracted from plants of the family Asteraceae. There are many unexploited plants that are regularly consumed and that may have a prebiotic effect or can have very high levels of inulin which could make them commercially viable. In this study, we investigated prebiotic compounds, especially inulin from locally growing, non-commercialised leafy plants. The aqueous extracts of 22 plants from the families Asparagaceae, Alliaceae, Asteraceae, Solanaceae, Cucurbitaceae, Amaranthaceae, Acanthaceae, Polygonaceae, Portulaceae, Fabaceae, Chenopodiaceae, Pedaliaceae and Apiaceae from Kwa-Zulu Natal were investigated for a prebiotic effect using a modified batch-culture technique with Lactobacillus bulgaricus, Lactobacillus lactis, Lactobacillus reuteri and Bifidobacterium longum, four common probiotics and the inulin content of the plants was determined using high performance liquid chromatography. Of the 22 plants studied, Solanum nigrum, Amaranthus spinosus, Amaranthus hybridus, Asystasia gangetica, Senna occidentalis, Cerathoteca triloba, Asparagus sprengeri, Tulbaghia violacea, Sonchus oleraceus and Taraxacum officinale exhibited a prebiotic effect. The prebiotic effect of the Taraxacum officinale, Sonchus oleraceus and Asparagus sprengeri extracts on L. lactis and L. reuteri was higher than or equivalent to inulin-a commercial prebiotic. In this study, Sonchus oleraceus exhibited the best prebiotic effect-was the only plant to stimulate all the probiotics including B. longum. Of all the plants analysed, Asparagus sprengeri tuber contained the highest amount of inulin (3.55%).
72

Application of thermostable a-Amylase from Thermomyces lanuginosus ATCC 58157 to nutritionally enhance starch based food

Padayachee, Thiriloshani January 2006 (has links)
Thesis (D. Tech.: Biotechnology)-Dept. of Biotechnology, Durban University of Technology, 2006 xii, 274 leaves / In Sub-Saharan Africa there is an urgent need to sustain and improve the quality of its food resources. Poverty eradication features high on the agenda of a number of world health organisations, while the number of underweight children in Africa continues to increase (Pellet, 1996). Providing nutritionally enhanced foods to the poor will help towards achieving this objective. Protein-energy malnutrition has been identified as one of the most important problems facing Africa, with maize as the staple diet (Nkama et al., 1995). However, a combination of several factors limits availability and the nutritional quality of maize. During starvation, energy and protein intakes decrease by 20-30%, with most of the children in Africa having an average protein intake of only 20 g per day (Igbedioh, 1996). Energy availability also affects protein utilization because of interrelationships of protein and energy metabolism (Elwyn, 1993). The diets of inhabitants in developing regions depend mainly on cereals (maize) for both protein and dietary energy which lacks indispensable amino acids, minerals, vitamins and carbohydrates. In light of these growing concerns an attempt was made to devise a scientific strategy to combat the nutritional shortfalls of maize meal. A multidisciplinary and concerted approach was followed within this project aimed at designing an improved thermostable amylase and applying the enzyme to nutritionally enhance maize meal. It was envisaged that the manipulation of maize meal, by the application of enzyme technology will improve the nutritional status of this staple food. The consequences is that an alternate solution for the eradication of an ailing, poverty stricken and malnourished African population is achievable. It is possible that the boundaries defining the limits of life will extend to even greater extremes through the application of novel technologies.
73

Aplicação da metodologia de APPCC - análise de perigos e pontos críticos de controle - como ferramenta para reúso de água na indústria: modelo para indústria de aromas e essências. / Aplication of HACCP methodology - hazard analysis and critical control point - as a water reuse tool in the industry: model to the aromatic and fragrancy industry.

Franco, Max Joel Mucha 24 April 2007 (has links)
Uma das maiores preocupações da indústria de alimento é o grande consumo de água nos seus processos produtivos. A conservação e reúso da água é hoje uma necessidade real e crescente. Esta dissertação expõe conceitos sobre uso racional e reúso de água na indústria de aditivos alimentares, e sistemas de gestão da qualidade na indústria de alimentos. O objetivo principal deste trabalho foi desenvolver uma descrição da aplicação do sistema APPCC - Análise de Perigos e Pontos Críticos de Controle, como ferramenta no reúso de águas para as indústrias de alimentos, utilizando-se como estudo de caso uma indústria do setor de aromas e essências, fundamentado nos princípios da Gestão da Qualidade Total. Neste estudo são apresentados dados técnicos obtidos em visitas realizadas à empresa Givaudan, localizado na cidade de São Paulo, Brasil. Foi feita uma análise dos principais processos produtivos, para a identificação da demanda de água e, consequentemente, das áreas com maior potencial para a aplicação de alternativas para reúso da água. Determinou-se que os maiores consumos de água estão na produção de aromas e fragrâncias, referindo-se ao processo de lavagem de equipamentos e utensílios nas áreas de secagem de emulsões e tanques móveis. Recomenda-se tratar o efluente da operação de lavagem, posteriormente essa água tratada deve ser levada a um tanque de armazenamento para ser reusada internamente nos primeiros estágios de lavagem e enxágüe dos secadores do tipo Spray Dry. A ferramenta APPCC vai garantir a qualidade físico-química e microbiológica da água. O tratamento para este efluente que contém alta concentração de sólidos dissolvidos é através de osmose reversa por ser um processo que vai permitir uma alta remoção dos sólidos dissolvidos, bactérias e vírus. Para reduzir o consumo de água na empresa se propor um reúso de água não potável externamente, implantando e instalando uma estação de tratamento biológico para adequar o efluente proveniente da área de lavagens dos tanques móveis, lavadores de gases, vasos sanitários, e bebedouros. / One of the major problems faced by the food industry is their enormous water consumption is their productive processes. Water conservation and reuse is a real and increasing necessity. This dissertation discusses rational use concepts, industrial water reuse, quality management systems in the condiment sector of the food industry. The main objective of this dissertation is to develop the concept of HACCP - Hazard Analysis and Critical Control Point - as a tool for water reuse in food industries, using the Flavor and Essence of food industry as a case study for total quality management. Presented in this study are the technical data obtained from Givaudan, a food industry located in the city of São Paulo, Brazil. The analysis of the main productive processes was done in order to identify the water demand and consequently, identify the areas where water reuse alternatives have more chances of being implemented. The major water consuming sectors in the company are the flavor and fragrance, ones especially, with equipment washing operations and utensils used in drying of emulsions and mobile tanks. One sends regards to deal with the effluent one the operation of laundering, later this treated water must be taken to a tank of storage to be reused internally in the first periods of training of laundering and rinses of the driers of the type Spray Dry. Tool APPCC goes to guarantee the quality microbiological physicist-chemistry and of the water. The treatment for this effluent one that it contains high dissolved solid concentration is through reverse osmosis for being a process that goes to allow one high removal of dissolved solids, bacteria and virus. To reduce the water consumption in the company if to consider one reuse externally of not potable water, implanting is installing a station of biological treatment to adjust effluent the proceeding one from the area of launderings of the mobile, washing tanks of gases, sanitary vases, and watering place.
74

Aplicação da metodologia de APPCC - análise de perigos e pontos críticos de controle - como ferramenta para reúso de água na indústria: modelo para indústria de aromas e essências. / Aplication of HACCP methodology - hazard analysis and critical control point - as a water reuse tool in the industry: model to the aromatic and fragrancy industry.

Max Joel Mucha Franco 24 April 2007 (has links)
Uma das maiores preocupações da indústria de alimento é o grande consumo de água nos seus processos produtivos. A conservação e reúso da água é hoje uma necessidade real e crescente. Esta dissertação expõe conceitos sobre uso racional e reúso de água na indústria de aditivos alimentares, e sistemas de gestão da qualidade na indústria de alimentos. O objetivo principal deste trabalho foi desenvolver uma descrição da aplicação do sistema APPCC - Análise de Perigos e Pontos Críticos de Controle, como ferramenta no reúso de águas para as indústrias de alimentos, utilizando-se como estudo de caso uma indústria do setor de aromas e essências, fundamentado nos princípios da Gestão da Qualidade Total. Neste estudo são apresentados dados técnicos obtidos em visitas realizadas à empresa Givaudan, localizado na cidade de São Paulo, Brasil. Foi feita uma análise dos principais processos produtivos, para a identificação da demanda de água e, consequentemente, das áreas com maior potencial para a aplicação de alternativas para reúso da água. Determinou-se que os maiores consumos de água estão na produção de aromas e fragrâncias, referindo-se ao processo de lavagem de equipamentos e utensílios nas áreas de secagem de emulsões e tanques móveis. Recomenda-se tratar o efluente da operação de lavagem, posteriormente essa água tratada deve ser levada a um tanque de armazenamento para ser reusada internamente nos primeiros estágios de lavagem e enxágüe dos secadores do tipo Spray Dry. A ferramenta APPCC vai garantir a qualidade físico-química e microbiológica da água. O tratamento para este efluente que contém alta concentração de sólidos dissolvidos é através de osmose reversa por ser um processo que vai permitir uma alta remoção dos sólidos dissolvidos, bactérias e vírus. Para reduzir o consumo de água na empresa se propor um reúso de água não potável externamente, implantando e instalando uma estação de tratamento biológico para adequar o efluente proveniente da área de lavagens dos tanques móveis, lavadores de gases, vasos sanitários, e bebedouros. / One of the major problems faced by the food industry is their enormous water consumption is their productive processes. Water conservation and reuse is a real and increasing necessity. This dissertation discusses rational use concepts, industrial water reuse, quality management systems in the condiment sector of the food industry. The main objective of this dissertation is to develop the concept of HACCP - Hazard Analysis and Critical Control Point - as a tool for water reuse in food industries, using the Flavor and Essence of food industry as a case study for total quality management. Presented in this study are the technical data obtained from Givaudan, a food industry located in the city of São Paulo, Brazil. The analysis of the main productive processes was done in order to identify the water demand and consequently, identify the areas where water reuse alternatives have more chances of being implemented. The major water consuming sectors in the company are the flavor and fragrance, ones especially, with equipment washing operations and utensils used in drying of emulsions and mobile tanks. One sends regards to deal with the effluent one the operation of laundering, later this treated water must be taken to a tank of storage to be reused internally in the first periods of training of laundering and rinses of the driers of the type Spray Dry. Tool APPCC goes to guarantee the quality microbiological physicist-chemistry and of the water. The treatment for this effluent one that it contains high dissolved solid concentration is through reverse osmosis for being a process that goes to allow one high removal of dissolved solids, bacteria and virus. To reduce the water consumption in the company if to consider one reuse externally of not potable water, implanting is installing a station of biological treatment to adjust effluent the proceeding one from the area of launderings of the mobile, washing tanks of gases, sanitary vases, and watering place.
75

Dietary modulation of the human colonic microbiota through plant-derived prebiotic compounds

Kassim, Muhammad Arshad January 2007 (has links)
Thesis (M.Tech.: Biotechnology)- Dept. of Biotechnology, Durban University of Technology, 2007 xv, 127 leaves / The human gut microbiota play a major role in host health, and attempts are being made to manipulate the composition of the gut microbiota-increase the composition of bacterial groups, such as lactobacilli and bifidobacteria that are perceived as exerting health promoting properties. These bacteria defined as food supplements (probiotics) beneficially affect the host by improving the intestinal microbial balance, and have been used to change the composition of the colonic microbiota. However, such changes may be transient, and the implantation of exogenous bacteria therefore becomes limited. In contrast, prebiotics are naturally occurring carbohydrates that are classified as non-digestible oligosaccharides present in edible plants. These carbohydrates enter the colon as intact compounds, elicit systemic physiological functions and act as fermentable substrates for colonic microflora-influencing the species composition and metabolic characteristics of intestinal microflora providing important health attributes. Currently, a widely marketed prebiotic, inulin is extracted from plants of the family Asteraceae. There are many unexploited plants that are regularly consumed and that may have a prebiotic effect or can have very high levels of inulin which could make them commercially viable. In this study, we investigated prebiotic compounds, especially inulin from locally growing, non-commercialised leafy plants. The aqueous extracts of 22 plants from the families Asparagaceae, Alliaceae, Asteraceae, Solanaceae, Cucurbitaceae, Amaranthaceae, Acanthaceae, Polygonaceae, Portulaceae, Fabaceae, Chenopodiaceae, Pedaliaceae and Apiaceae from Kwa-Zulu Natal were investigated for a prebiotic effect using a modified batch-culture technique with Lactobacillus bulgaricus, Lactobacillus lactis, Lactobacillus reuteri and Bifidobacterium longum, four common probiotics and the inulin content of the plants was determined using high performance liquid chromatography. Of the 22 plants studied, Solanum nigrum, Amaranthus spinosus, Amaranthus hybridus, Asystasia gangetica, Senna occidentalis, Cerathoteca triloba, Asparagus sprengeri, Tulbaghia violacea, Sonchus oleraceus and Taraxacum officinale exhibited a prebiotic effect. The prebiotic effect of the Taraxacum officinale, Sonchus oleraceus and Asparagus sprengeri extracts on L. lactis and L. reuteri was higher than or equivalent to inulin-a commercial prebiotic. In this study, Sonchus oleraceus exhibited the best prebiotic effect-was the only plant to stimulate all the probiotics including B. longum. Of all the plants analysed, Asparagus sprengeri tuber contained the highest amount of inulin (3.55%).
76

Application of thermostable a-Amylase from Thermomyces lanuginosus ATCC 58157 to nutritionally enhance starch based food

Padayachee, Thiriloshani January 2006 (has links)
Thesis (D. Tech.: Biotechnology)-Dept. of Biotechnology, Durban University of Technology, 2006 xii, 274 leaves / In Sub-Saharan Africa there is an urgent need to sustain and improve the quality of its food resources. Poverty eradication features high on the agenda of a number of world health organisations, while the number of underweight children in Africa continues to increase (Pellet, 1996). Providing nutritionally enhanced foods to the poor will help towards achieving this objective. Protein-energy malnutrition has been identified as one of the most important problems facing Africa, with maize as the staple diet (Nkama et al., 1995). However, a combination of several factors limits availability and the nutritional quality of maize. During starvation, energy and protein intakes decrease by 20-30%, with most of the children in Africa having an average protein intake of only 20 g per day (Igbedioh, 1996). Energy availability also affects protein utilization because of interrelationships of protein and energy metabolism (Elwyn, 1993). The diets of inhabitants in developing regions depend mainly on cereals (maize) for both protein and dietary energy which lacks indispensable amino acids, minerals, vitamins and carbohydrates. In light of these growing concerns an attempt was made to devise a scientific strategy to combat the nutritional shortfalls of maize meal. A multidisciplinary and concerted approach was followed within this project aimed at designing an improved thermostable amylase and applying the enzyme to nutritionally enhance maize meal. It was envisaged that the manipulation of maize meal, by the application of enzyme technology will improve the nutritional status of this staple food. The consequences is that an alternate solution for the eradication of an ailing, poverty stricken and malnourished African population is achievable. It is possible that the boundaries defining the limits of life will extend to even greater extremes through the application of novel technologies.
77

Exploring the influence of external product attributes on consumers' perceived acceptance of pea protein as a protein substitute in food products

Quinn, Tineke 07 1900 (has links)
The purpose of this study was to explore the influence of external product attributes on consumers’ perceived acceptance of pea protein as a protein substitute in food products. The interest in pea protein as a possible protein source was investigated and the various advantages of consuming pea protein were highlighted. In previous studies, pea protein was identified as a possible substitute for red meat (Davies & Lightowler, 1998), but also as protein containing the amino acid profile which corresponds with the profile recommended for adults by the Food and Agriculture Organisation (FAO) (Swendseid, 1981). Additionally the nutritional and health benefits, the environmental benefits of growing pea protein as well as the non-allergen declaration accompanying pea protein were discussed. The various factors that will influence the consumer’s decision making process when introduced to a new and unfamiliar protein source such as pea protein were investigated in terms of the external product attributes as well as the factors indicated in the Theory of Reasoned Action (TRA) (Fishbein & Ajzen, 1975). The external product attributes were identified as the influence of price, marketing of the product, packaging attributes of new food products, branding importance of a product and new product education and knowledge perceived necessary for acceptability of a new food product. The additional factors which were investigated, as indicated by the TRA, included the influence of the subjective norms or significant others, as well as the consumers’ personal attitude. attitude. Due to the limited insight and understanding of the influences that external product attributes have on a consumer’s perceived acceptance of pea protein as a protein substitute in food products, a qualitative exploratory research design was initiated. An exploratory research design was incorporated because this afforded the researcher the opportunity to gather thorough and comprehensive data or information and it also increased the richness and depth of explorations that could be researched (Key, 2002). The fact that an exploratory research design was incorporated, a non-probability sampling strategy was implemented. Additionally a convenient sampling strategy was also implemented because this type of sampling strategy represents sites or individuals from which data can easily be collected and where access is convenient (Cresswell, 2007). The unit of analysis for this research was female shoppers, being the main grocery and food shoppers in the household, who were living in suburban areas. The participants of the research, therefore, resided mainly in the Johannesburg and Pretoria suburban areas, within the Gauteng province and were chosen because these are two of the major suburban cities in South Africa. The data were collected through means of a multi-method approach whereby different data collection instruments were applied. In this regard focus group interviews, sentence completion exercise and a vignette were used which addressed the objectives set out in the study. From the findings of the study on the influence of external product attributes on consumers’ perceived acceptance of new products in general and new products containing pea protein, it was found that there were not any noticeable differences between a new food product and a new food product containing pea protein. The consumer did not indicate a greater willingness to accept general new products in comparison to a pea protein product. On the contrary, the fact that a new product contained pea protein did not make any difference. For consumers external product attributes in general played a major role in their purchasing decision making process. The most important requirement that the consumers had was that additional information regarding the pea protein should be provided. It was indicated by the participants that they would be interested in the pea protein product and consider purchasing it and incorporating it into their daily diet, providing they knew more about the product and had sufficient background information about the new product. Furthermore, the importance of marketing of a new product was highlighted and the fact that the packaging of the new product should be attractive and eye-catching. Price competiveness was mentioned, however, should a new and unfamiliar product be introduced by a well-known brand, this would lower the initial resistance to the new product. One of the main limitations of this study is the relatively small sample size from a particular area in South Africa and, therefore, resulting in a very selective sample. The sample, therefore, remains one of convenience which limits the ability to generalize or transfer findings to a bigger group of consumers. Furthermore the study location was within a limited area, namely Gauteng. For this reason no assumptions were made nor were findings considered to be transferable to other population groups or consumer groups. Another limitation is that the topic of this study is very new and unfamiliar; there are, therefore, no previous studies with which to compare the findings. This study was exploratory in nature and the instruments were chosen specifically to explore a new and unfamiliar topic. The transferability of this study might be limited, but care was taken to describe the research context in as much detail as possible. In doing so, an attempt was made to enhance the transferability, should another researcher wish to duplicate the study. From the findings of this study certain recommendation can be made as most participants were of the opinion that they would be interested in the pea protein product and consider purchasing it and incorporating it into their daily diet provided they knew more about the product and sufficient background information had been supplied. Furthermore, it was noted from the findings that these external attributes would influence the new product acceptability and, therefore, giving the research and developers as well as the marketing team of a manufacturing company the information necessary to understand the requirements from the consumers regarding the product containing pea protein better and how this product should be marketed as a healthy alternative to other vegetable protein sources. Further recommendations are that should a food manufacturing company wish to develop a pea protein product, they would need to promote the product beforehand and create an awareness of the advantages and benefits of pea proteins. This can be done by editorials in magazines as well as promotions in printed media. Additionally, the competition between products and brands is fierce and, therefore, manufacturing companies need to differentiate their products to keep consumers interested in their product or brand. Pea protein is a new and innovative product and can, therefore, add that differentiation and benefit to food products. Future research that can be considered is that of a sensory study, to determine the actual viability of the pea protein products based on sensory evaluation. One of the main criteria indicated for the acceptability of a food product containing pea protein has been the taste. The present research was theoretical and exploratory in nature and, therefore, there were no actual products which the participants could taste. Additionally, the inclusion criteria for this study was identified as female shoppers who are in charge of household grocery and food purchases and were, therefore, specifically recruited to participate in the research. However, based on a study done by Jensen (2011), it is recommended that further studies specifically include males because men are doing more of the household grocery shopping and they are not as brand loyal as females and would, therefore, be more willing to try and experiment with new food products. A study based on the gender differences of the acceptability of new products, could highlight different extrinsic attributes that would influence the purchasing decision. / Business Management / M. Consumer Sc.
78

Vitamin B12 and folate enrichment of kefir by Propionibacterium freudenreichii and Streptococcus thermophilus strains

Morkel, Ryan Andrew January 2016 (has links)
Thesis (MTech (Food Technology))--Cape Peninsula University of Technology, 2016. / In South Africa malnutrition exists due to inadequate dietary intake of micronutrients which is one of the major causes of vitamin deficiencies leading to disease. The treatment of malnutrition over the past years has been a considerable burden on the South African economy. Therefore, food fortification is one of the current strategies used to minimize malnutrition by increasing the nutritional value of staple foods. Commercial dairy products and pharmaceutical nutritional products (food supplements) in South Africa have been developed and produced for affluent consumers. Hence the need to develop an affordable fortified dairy product for the majority of South Africans prompted this study aimed at using a “naturally” fortified kefir beverage with vitamin B12 and folate to increase B-vitamins levels. Since Propionibacterium freudenreichii and Streptococcus thermophilus are known to be good producers of vitamin B12 and folate, respectively, and propionibacteria has the ability to grow symbiotically in the presence of lactic acid bacteria, the inclusion of these organisms with the kefir grains was an achievable objective. In order to conduct the analysis of vitamin B12 and folate in the samples, sample extraction and HPLC assay techniques were developed. The extraction of vitamin B12 and folate were achieved by using KCN extraction buffer and the trienzymatic method, respectively. The samples were also subjected to purification and concentration using solid phase extraction for optimum results. All standards and samples were flushed with nitrogen gas and stored for a maximum of 2 weeks at –20°C to prevent B-vitamin deterioration. The HPLC assembly for the vitamin B12 analysis included a Luna C18 column and a diode array detector (DAD) for the detection and quantification. For the folate analysis it included a Zorbax SB-C18 and Luna C18 columns in tandem and the fluorescence detector (FLD) was used for the detection and quantification of THF, 5-CH3-THF and 5-CHO-THF, while the DAD was used for PGA and pteroyltri-γ-L-glutamic acid concentration in the samples.
79

Desenvolvimento e aplica??o do teste desafio em refrigerante de laranja adicionado de concentrado de cenoura e ma?? / Development and application of microbiological challenge test (MCT) in orange soda added with carrot and apple concentrate

AZEREDO, Denise Rosane Perdomo 25 August 2016 (has links)
Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2017-05-19T18:26:23Z No. of bitstreams: 1 2016 - Denise Rosane Perdomo Azeredo.pdf: 2006973 bytes, checksum: 610e1499e6733b78ee2eb47034198a7d (MD5) / Made available in DSpace on 2017-05-19T18:26:23Z (GMT). No. of bitstreams: 1 2016 - Denise Rosane Perdomo Azeredo.pdf: 2006973 bytes, checksum: 610e1499e6733b78ee2eb47034198a7d (MD5) Previous issue date: 2016-08-25 / Nowadays consumer desired healthy foods that promote benefits and free from food additives. The chemical composition of soft drinks, artificial colors and preservative, may pose a risk to consumer health due to the possibility of benzene formation, a recognized carcinogenic agent in humans and the association between artificial colors, allergic reactions and DNA damage. In this study, an orange soda formula containing the preservatives sodium benzoate and potassium sorbate with carrot and apple concentrate was developed. In parallel, we developed a standard formula containing tartrazine and sunset yellow. Physicochemical, microbiological and sensory analysis of formulas were carried out during the storage period of 150 days. It was observed that there were no changes in physicochemical parameters. However, the colorimetric analysis revealed a short shelf life in the sample containing the carrot and apple concentrate. Regarding microbiology, both formulations were according to regulation by public health agencies. The yeasts and molds counts presented 1 log cycle growth in the formula containing the carrot and apple concentrate, suggesting that the robustness of the developed matrix may be affected, if the hygiene conditions of processing line sanitation are not observed. It was found that the color was the sensory characteristic that most influenced consumers regarding the acceptability of the samples, signaling that this parameter interfered significantly in evaluating flavor and appearance The results obtained by microbiological challenge test and determination of growth potential (?) indicated that yeast and lactic acid bacteria are able to multiply in the formula containing carrot and apple concentrate without preservatives (? ? 0.5 log10), indicating that the formula is sensitive. Acid acetic bacteria, in these conditions, were inhibited. A preserved formula with the addition of carrot and apple concentrate and other formula with the addition of artificial colors were prepared. The results referring to the growth potential (?) indicated that yeast and lactic acid bacteria were inhibited (? ? 0.5 log10) in both formulas. However, the preservative resistant yeasts presented growth ability (? ? 0.5 log10). In the apple and carrot concentrate, it was observed that yeast, lactic acid bacteria and fungus Penicillium citrinum were inhibited, indicating that this ingredient should not be considered a nutrient source for microbial multiplication that would affect the formula robustness. It was verified the growth of the preservative resistant yeasts (growth potential ? ? 0,5 log10) in all the evaluated formulas and ingredient. The data obtained, in this study, indicate that the development of more natural foods still represents a challenge for the food industry. / Atualmente o consumidor anseia por alimentos mais naturais, saud?veis, que promovam benef?cios ? sa?de e que sejam isentos de aditivos. Nesse sentido, a composi??o qu?mica dos refrigerantes, especialmente no que concerne aos corantes artificiais e conservadores pode representar riscos ? sa?de do consumidor, devido a possibilidade de forma??o de benzeno, reconhecido agente carcinog?nico ao homem, e a associa??o entre corantes artificiais, rea??es al?rgicas e efeitos delet?rios ao DNA. Nessa pesquisa, inicialmente, desenvolveu-se uma formula??o de refrigerante de laranja, contendo os conservadores benzoato de s?dio e sorbato de pot?ssio, na qual os corantes artificiais ? amarelo tartrazina e amarelo crep?sculo foram substitu?dos por concentrado de cenoura e ma??. Em paralelo, desenvolveu-se uma formula??o controle. Foram realizadas an?lises f?sico-qu?micas, microbiol?gicas e sensorial das formula??es durante o per?odo de armazenamento de 150 dias. Observou-se o atendimento ao padr?o de identidade e qualidade e estabilidade das formula??es em rela??o aos par?metros f?sico-qu?micos. Entretanto, na an?lise colorim?trica observou-se uma degrada??o de cor percept?vel ao consumidor na amostra contendo o concentrado de cenoura e ma??. Em rela??o as an?lises microbiol?gicas, ambas as formula??es atenderam aos par?metros preconizados pela legisla??o. Entretanto, a contagem de bolores e leveduras apresentou crescimento de 1 ciclo log na formula??o contendo o concentrado de cenoura e ma??, sugerindo que a robustez da matriz desenvolvida pode ser afetada, se as condi??es de higieniza??o da linha de processamento n?o forem observadas. Em rela??o a an?lise sensorial, verificou-se que a cor foi a caracter?stica sensorial que mais influenciou os consumidores com rela??o a aceitabilidade das amostras, sinalizando que esse par?metro interferiu, de forma significativa na avalia??o do sabor e apar?ncia. Os resultados referentes a aplica??o do teste desafio e a determina??o do potencial de multiplica??o microbiana (?) indicaram que as leveduras e bact?rias l?cticas s?o capazes de se multiplicar na formula??o adicionada de concentrada de cenoura e ma?? sem conservadores (? ? 0,5 log10), sinalizando que a formula??o ? sens?vel. As bact?rias ac?ticas, nessas condi??es, foram inibidas. Nas formula??es preservadas quimicamente com adi??o de concentrado de cenoura e ma?? e a adicionada de corantes artificiais, os resultados referentes ao potencial de multiplica??o microbiana (?) indicaram que as leveduras e bact?rias l?cticas foram inibidas (? ? 0,5 log10) em ambas as formula??es. Entretanto, as leveduras resistentes a conservadores apresentaram habilidade de crescimento (? ? 0,5 log10). No ingrediente concentrado de cenoura e ma??, observou-se que as leveduras, bact?rias l?cticas e o fungo Penicillium citrinum foram inibidos, indicando que o concentrado n?o deve ser considerado uma fonte de nutriente para a multiplica??o microbiana que afetaria a robustez da formula??o. Constatou-se a multiplica??o das leveduras resistentes a conservadores, com potencial de multiplica??o ? ? 0,5 log10 em todas as formula??es e ingrediente avaliados. Os dados obtidos no presente estudo sinalizam que o desenvolvimento de alimentos mais naturais ainda representa um desafio para a ind?stria de alimentos.
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Zásady zdravého životního stylu a jejich uplatnění v pedagogické praxi / Healthy Lifestyle Principles and Their Use in Teaching Practise

Prknová, Monika January 2019 (has links)
The thesis "A healthy lifestyle and its application in teaching practice" covers the principles of a healthy lifestyle among today̕ s secondary school students and their application in life. The author compares the differences in the healthy lifestyle of secondary school student, how they are interpreted by professionals, and compares them with the results of questionnaire conducted among pupils and their parents in the 2015/2016 school year at SŠ-COPTH (High School - Technical and Vocational Trainning Centre), Poděbradská 12, Prague 9, in the chemist operator and car mechanic fields. The conclusions that the author has come to show to what extent today̕ s secondary school students, whether studying graduation courses or apprenticeships, enjoy a healthy lifestyle and the degree of their motivation to take care of their health. Work on this topic has led the author to reflect on how to continue to reach out to young people to ensure that they maintain a healthy lifestyle. KEY WORDS: health, healthy lifestyle, student motivation, education towards health, food additives

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