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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

Life cycle assessment of the production of edible oil emulsions : comparing a novel process route using aqueously extracted oil-bodies against existing technology

Hetherington, Alexandra Claire January 2014 (has links)
It is estimated that over a third of the diet in the Western world is made up of oils and fats, of which a prominent percentage is in the form of emulsion food products, including milks, creams, yoghurts, margarines, salad dressings, desserts, soups and cheese. Current processing techniques involve the extraction and refining of edible oils using high temperatures and organic solvents, followed by re-encapsulation of the oil, for incorporation into the required emulsion products. The research presented in this PhD thesis was performed within the auspices of the UK Department of Environment, Food and Rural Affairs (DEFRA) funded, Sustainable Emulsion Ingredients through Bio-Innovation (SEIBI) project, which involved collaboration with researchers from the University of Nottingham together with a consortium of industrial partners. SEIBI was initiated to investigate a novel processing route for the production of food-grade rape and sunflowerseed oil emulsions from aqueously extracted oil-bodies. Being less energy and chemical intensive, the novel process offered potential reductions in both greenhouse gas emissions and wider environmental impacts when compared with conventional processing. Using Life Cycle Assessment (LCA) techniques, the environmental burdens of the aqueous oil-body extraction process were determined and compared with those of the existing technology route. To facilitate this, the research focussed on six key objectives, designed to both identify the environmental loads of the systems involved and scrutinise the impact of a number of methodological choices for LCA. These included choice of allocation method, normalisation, scaling issues distinct for novel processes and the extent to which the single-issue LCA variant, carbon footprinting could be used as an environmental indicator for the system. LCAs for four separate categories of product systems were developed encompassing seed oils, mayonnaises, aqueously extracted oil-body materials and mayonnaise-like oil-body emulsions. In addition to generating the environmental profiles required to fulfil the research objectives, the analysis of these models enabled the generation of original knowledge through the quantification of impacts for a range of processes that had either not previously been assessed or for which no published data could be found. The novel process was concluded as having clear potential for improved environmental performance over current technology even in its' pre-optimised, although the methodological choices examined were found to have profound effects on these and other results. Oil-body yield from seed was identified as key for optimisation to further maximise the environmental gains, with modest improvements, well within those theoretically possible being required for the novel process to better the environmental credentials of current technology in all key impact areas. The original outputs from this thesis will be of considerable use to developers involved in the continued advancement of the oil-body extraction technology, together with researchers within the edible oils and emulsions sector. In addition, the methodological outputs will help to inform LCA practitioners and developers in the continuing quest to understand the capabilities and limitations of this powerful analytical tool.
162

Efeito da adição de nanoestruturas, óleos essenciais e quitosana no desenvolvimento de filmes e coberturas biodegradáveis com propriedades antioxidantes e antimicrobianas

Pagno, Carlos Henrique January 2016 (has links)
A principal função das embalagens tradicionais utilizadas pela indústria de alimentos é a proteção dos alimentos de contaminações externas sem interagir com o mesmo. No entanto, a maioria dessas embalagens é produzida a partir de fontes não biodegradáveis e não renováveis. Para atender à crescente demanda em relação à sustentabilidade ambiental, os filmes e coberturas comestíveis têm despertado o interesse e atenção por parte de indústrias e pesquisadores. Além disso, tais filmes ou coberturas podem ser acrescidos de diferentes compostos, para conferir as mesmas um caráter ativo, com interação positiva com os alimentos, para auxiliar a conservação. Dessa forma, este trabalho teve por objetivo (1) desenvolver filmes ativos pela técnica de casting a partir de matrizes biodegradáveis, com atividade antimicrobiana devido a incorporação de nanopartículas de ouro (AuNPs) e óleos essenciais, além de filmes com atividade antioxidante pela adição de nanocápsulas de bixina, (2) avaliar as características mecânicas, físicas e de barreira dos filmes ativos, além da atividade antimicrobiana e antioxidante, e (3) verificar a eficiência na aplicação de coberturas comestíveis na conservação de alimentos. Os filmes com atividade antimicrobiana utilizaram como matérias primas o amido e a farinha integral de grãos quinoa (Chenopodium quinoa W.). Os filmes de amido de quinoa foram preparados com 4 % de matéria prima e 1 % de glicerol como plastificante e incorporados com solução de nanopartículas de ouro nas concentrações de 2,5 % e 5 % (v/v). A presença de AuNPs levou a uma melhoria nas propriedades mecânicas, ópticas e morfológicas dos filmes, sem alterar as propriedades térmicas e de barreira, além de exibirem forte atividade antibacteriana contra agentes patogênicos de origem alimentar, com porcentagens de inibição de 98 % contra E. coli e S. aureus. Nos filmes ativos elaborados com a farinha de quinoa (6 % de matéria prima e 1 % de glicerol como plastificante em 100 g de solução filmogênica), foram adicionados os óleos essenciais (OE) de orégano (Origanum vulgare L.) e tomilho (Thymus vulgaris L.) (0,5 %, 1 % e 2 % p/p). Observou-se que o tipo de OE não interferiu significativamente nos parâmetros físicos e de barreira dos filmes. Já o aumento na concentração dos OEs, produziu filmes mais elásticos e menos resistentes, bem como, menos solúveis em água e com menor permeabilidade aos vapores de água. Os filmes com 1 % e 2 % de OEs exibiram um efeito inibidor sobre o crescimento de S. aureus e E. coli. No entanto, o S. aureus mostrou-se mais sensível a ambos os OEs; e os filmes com orégano foram mais eficazes na inativação de ambos os microrganismos. As embalagens antioxidantes foram elaboradas a partir de amido de mandioca (4 % de matéria prima e 1 % de glicerol como plastificante em 100 g de solução filmogênica) incorporadas com solução de nanocápsulas de bixina (0 %, 2 %, 5%, 8 % e 10 %). Os filmes foram caracterizados em relação as suas propriedades de barreira, mecânicas e físicas e a atividade antioxidante foi avaliada pelo efeito protetor do óleo de girassol exposto a condições de oxidação aceleradas (13 dias a 65 % UR / 35 ºC). Embalagens com maiores concentrações de nanocápsulas demonstraram maior resistência e elasticidade, bem como, uma melhora significativa na proteção contra os raios UV e luz visível. O óleo de girassol embalado nos filmes contendo nanocápsulas de bixina apresentaram índices de peróxidos abaixo dos estipulados pelo Codex Alimentarius (<10 meq. O2 kg-1) para óleos frescos para o período de armazenamento testado. A cobertura comestível foi preparada à base de quitosana (1,5 %) e foi aplicada sobre tomates armazenados por 14 dias (20 ° C), com acompanhamento da perda de peso, sólidos solúveis totais (SST), firmeza e acidez titulável (AT), taxa de respiração, produção de etileno e quantificação de carotenoides e compostos fenólicos por CLAE. Os frutos revestidos demonstraram retardo no processo de amadurecimento com a diminuição da taxa respiratória e produção de etileno, bem como menores perdas de peso, firmeza -caroteno e menor degradação de compostos fenólicos durante o armazenamento, em comparação com frutos controle (não revestidos). Os resultados sugerem que o desenvolvimento de filmes ativos para conservação de alimentos é um campo promissor, pois além do forte apelo ambiental, filmes ativos podem auxiliar na conservação dos alimentos, para retardar a proliferação de microrganismos patogênicos e degradações oxidativas. Em relação a aplicações de coberturas comestíveis, os resultados indicaram ter potencial para uma utilização comercial no auxílio de prolongamento da vida útil de tomates. / The principal function of traditional packaging used by the food industry is the protection of food against external contamination without interacting with it. However, most of these packages are produced from non-biodegradable and non-renewable sources. Films and edible coatings have attracted the interest and attention from industries and researchers due increasing demand on environmental sustainability. In addition, this films and coatings can be added with different compounds to confer an active character, with positive food interaction and increased of preservation. This study aimed to (1) to develop active films by casting technique from biodegradable matrices with antimicrobial activity, incorporated of gold nanoparticles (AuNPs) and essential oils, as well as films with antioxidant activity by addition of nanocapsules of bixin, (2) evaluate the mechanical, physical and barrier characteristics of active films, and capacity antimicrobial and antioxidant, and (3) verify the efficiency in the application of edible coatings in food preservation. The active antimicrobial films it was used as raw material starch and flour quinoa (Chenopodium quinoa, W.). Starch quinoa films were prepared with 4 % raw material and 1% glycerol as plasticizer (100 g filmogenic solution), incorporating gold nanoparticles at concentrations of 2.5% and 5% (v / v). The presence of gold nanoparticles produces improvement in the mechanical, optical and morphological properties, maintaining the thermal and barrier properties unchanged when compared to the standard biofilm. The active biofilms exhibited strong antibacterial activity against food-borne pathogens with inhibition percentages of 99 % against E. coli and 98 % against S. aureus. The active films produced with flour quinoa (6% of raw material and 1% glycerol as a plasticizer in 100 g of filmogenic solution), incorporated with oregano (Origanum vulgare L.) and thyme (Thymus vulgaris L.) essential oils (EO) (0.5%, 1% and 2% p/p). It was observed that the kind of EO was not significant for the physical and barrier parameters of the films, however, the increase in the EOs concentration promote increase in the elongation but decrease in the tensile strength, solubility and water vapor permeability. Films containing 1% and 2 % EOs, inhibit the growth of S. aureus and E. coli. However, S. aureus was more sensitive to both EOs and the oregano oil was more efficient in the inactivation to both microorganisms. The antioxidant packages were prepared from cassava starch (4% raw material and 1% glycerol as plasticizer in 100 g of filmogenic solution), incorporated with solution of different concentrations of bixin nanocapsules (0 %, 2 %, 5%, 8 % e 10 %). Films with higher concentrations of bixin nanocapsules exhibited significant reduction tensile strength and increases in elongation at break, well as, improvement in protection against UV and visible light and decreased water solubility and increased water vapor permeability. The sunflower oil packed in films containing nanocapsules bixin exhibited lower oxidation rates, thus maintaining its freshness according to Codex Alimentarius guidelines (< 10 milliequivalent.kg-1), for the storage time tested (13 days / 65 % RH / 35 ºC). The edible coating was prepared based on chitosan (1.5 %), and it was applied on tomatoes stored for 14 days (20 °C). The analyses carried out on tomato fruit were: weight loss, total soluble solid (TSS), firmness, and titratable acidity (TA), respiration rate, ethylene production and quantification of carotenoids and phenolics by HPLC. Coated fruit delayed the ripening process by decrease of the rate of respiration and ethylene production, as well changes of weight, firmness and TSS concentration and delay peak of lycopene and b-carotene accumulation and degradation of phenolic compounds during storage, compared to uncoated control. The results suggest that the development of active films for food preservation is a promising field, because besides the strong environmental appeal, active films can increase the food preservation, to decrease the proliferation of pathogenic microorganisms and oxidative degradation. Regarding the edible coatings applications, the results indicated that coating is a promising tool for commercial use in helping to prolong the storage of tomatoes.
163

Preparação e caracterização de filmes comestíveis baseados em gelatina, chá-verde e nanoemulsão de óleo essencial de limão /

Nunes, Juliana Carla January 2018 (has links)
Orientador: Marcia Regina de Moura Aouada / Resumo: Diante da crescente preocupação com os impactos ambientais relacionados ao uso de polímeros sintéticos, estudos visando à obtenção e aplicação de materiais poliméricos de fontes renováveis vêm aumentando, como por exemplo, o desenvolvimento de filmes comestíveis à base de polímeros naturais. Para a obtenção de filmes comestíveis necessita-se de um material polimérico que forme uma matriz homogênea e contínua. A gelatina é um polímero natural, de fonte abundante, biodegradável e biocompatível e tais características motivam sua utilização como matriz em filmes comestíveis. O uso de extrato de chá-verde e óleo essencial de limão em filmes de gelatina é uma alternativa para melhoria de suas características físicas e organolépticas para uma aplicação inovadora do produto como sachê de chá. Neste contexto, o objetivo do presente estudo foi preparar, caracterizar e avaliar a influência do extrato de chá-verde e da nanoemulsão de limão nas propriedades de solubilidade, mecânicas, térmicas e de permeabilidade ao vapor de água da matriz de gelatina. A nanoemulsão apresentou tamanho médio de 171 ± 3 nm e potencial zeta de -10,9 ± 0,1 mV. Os filmes foram obtidos por casting a partir de soluções filmogênica de gelatina com extrato de chá verde e nanoemulsão de limão. A adição de chá verde ocasionou um aumento da tensão máxima de ruptura do filme de gelatina de 86 ± 7 MPa para 101 ± 5 MPa e quando a nanoemulsão foi adicionada o valor diminuiu para 78 ± 8 MPa. A incorporação de chá-verde e ... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: In view of the growing concern about the environmental impacts related to the use of synthetic polymers, studies aimed to obtain and apply polymeric materials from renewable sources have been increased, as the development of edible films based on natural polymers. To obtain edible films, a polymeric material is needed to form a homogeneous and continuous matrix. Gelatin is a natural polymer, from an abundant source, biodegradable and biocompatible and such characteristics motivate its use as a matrix in edible films. The use of green tea extract and lemon essential oil in gelatin films is an alternative to improve its physical and organoleptic characteristics for an innovative application of the product as a tea bag. In this context, the objective of the present study was to prepare, characterize and evaluate the influence of the green tea extract and the lemon nanoemulsion on the solubility, mechanical, thermal and water vapor permeability properties of the gelatin matrix. The nanoemulsion had an average size of 170.6 ± 3 nm and a zeta potential of -10.9 ± 0.1 mV. The films were obtained by casting from filmogenic solutions of gelatin with green tea extract and lemon nanoemulsion. The addition of green tea caused an increase in the maximum tensile stress of the gelatin film from 86 ± 7 MPa to 101 ± 5 MPa and when the nanoemulsion was added the value decreased to 78 ± 8 MPa. The incorporation of green tea and nanoemulsion increased the permeability of water vapor and the solu... (Complete abstract click electronic access below) / Mestre
164

In vitro and in vivo antioxidant activity and hypocholesterolemic effect in extracts of Agrocybe aegerita. / In vitro & in vivo antioxidant activity and hypocholesterolemic effect in extracts of agrocybe aegerita

January 2005 (has links)
Ng Yuk Fan. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2005. / Includes bibliographical references (leaves 145-162). / Abstracts in English and Chinese. / Thesis Committee: --- p.i / Acknowledgements --- p.ii / Abstract --- p.iii / 摘要 --- p.v / Content --- p.vii / List of Tables --- p.xiii / List of Figures --- p.xvi / Abbreviations --- p.xviii / Chapter Chapter 1: --- Introduction --- p.1 / Chapter 1.1 --- Antioxidants --- p.1 / Chapter 1.1.1 --- Definition and mode of actions of antioxidants --- p.1 / Chapter 1.1.2 --- Synthetic antioxidants --- p.2 / Chapter 1.1.3 --- Natural antioxidants --- p.3 / Chapter 1.2 --- Changes of antioxidant activity in food processing --- p.4 / Chapter 1.2.1 --- Blanching --- p.4 / Chapter 1.2.2 --- Drying --- p.5 / Chapter 1.2.3 --- Microwave and Infrared energy --- p.7 / Chapter 1.2.4 --- Freezing --- p.8 / Chapter 1.3 --- Lipid oxidation and antioxidant --- p.8 / Chapter 1.3.1 --- Free radicals --- p.8 / Chapter 1.3.1.1 --- Superoxide --- p.10 / Chapter 1.3.1.2 --- Hydrogen peroxide --- p.11 / Chapter 1.3.1.3 --- Hydroxyl radical --- p.13 / Chapter 1.3.2 --- Mechanism of lipid oxidation --- p.14 / Chapter 1.3.3 --- Oxidation of low-density-liporoproteins (LDLs) and coronary heart disease --- p.15 / Chapter 1.3.4 --- Role of antioxidants in inhibiting lipid oxidation --- p.16 / Chapter 1.4 --- Hypocholesterolemic and antioxidant activity of phenolics --- p.19 / Chapter 1.5 --- Medicinal properties of mushrooms --- p.21 / Chapter 1.5.1 --- Background information of mushrooms --- p.21 / Chapter 1.5.2 --- Phenolics in mushrooms --- p.22 / Chapter 1.5.3 --- Hypocholesterolemic effect in mushroom --- p.23 / Chapter 1.5.4 --- Previous studies in Agrocybe aegerita --- p.25 / Chapter 1.6 --- Animal model for hypocholesteroliemic study --- p.27 / Chapter 1.6.1 --- General requirements --- p.27 / Chapter 1.6.2 --- Hamster model --- p.27 / Chapter 1.7 --- Principles of assays that involved in antioxidant activity --- p.30 / Chapter 1.7.1 --- ABTS + radical cation scavenging activity --- p.30 / Chapter 1.7.2 --- Beta carotene bleaching method --- p.31 / Chapter 1.7.3 --- Ferric reducing antioxidant power (FRAP) --- p.31 / Chapter 1.7.4 --- Scavenging activity of hydroxyl radical --- p.32 / Chapter 1.7.5 --- Inhibition of low-density lipoproteins (LDLs) oxidation --- p.33 / Chapter 1.7.6 --- Total phenolic content determination --- p.33 / Chapter 1.8 --- Principles of assays in hypocholesterolemic study --- p.34 / Chapter 1.8.1 --- HDL-Cholesterol determination --- p.34 / Chapter 1.8.2 --- Total cholesterol determination --- p.34 / Chapter 1.8.3 --- Determination of plasma total triglyceride --- p.35 / Chapter 1.9 --- Objectives --- p.36 / Chapter Chapter 2: --- Materials and Methods --- p.37 / Chapter 2.1 --- Sample preparation --- p.37 / Chapter 2.2 --- Proximate Analysis of FAa and DAa --- p.38 / Chapter 2.2.1 --- Determination of crude protein --- p.38 / Chapter 2.2.2 --- Determination of ash --- p.39 / Chapter 2.2.3 --- Total dietary fiber --- p.39 / Chapter 2.2.4 --- Determination of fat --- p.41 / Chapter 2.2.5 --- Moisture content --- p.42 / Chapter 2.3 --- Sample extraction --- p.42 / Chapter 2.3.1 --- Small-scale extraction --- p.42 / Chapter 2.3.2 --- Large-scale extraction --- p.43 / Chapter 2.4 --- Total phenolic content of DAa and FAa extract --- p.44 / Chapter 2.5 --- Chemical assays for in vitro antioxidative properties determination --- p.45 / Chapter 2.5.1 --- Hydroxyl free radical scavenging activity --- p.45 / Chapter 2.5.2 --- Beta-carotene bleaching method --- p.46 / Chapter 2.5.3 --- Inhibition of human low-density-lipoproteins (LDLs) oxidation --- p.47 / Chapter 2.5.4 --- Scavenging activity of ABTS+radical cation --- p.50 / Chapter 2.6 --- In vivo tests for antioxidative and hypocholesterolemic effect of DAa --- p.51 / Chapter 2.6.1 --- Feeding experiments --- p.51 / Chapter 2.6.2 --- Collection of plasma --- p.52 / Chapter 2.6.3 --- Liver sample preparation --- p.52 / Chapter 2.6.4 --- Determination of in vivo antioxidative effect --- p.54 / Chapter 2.6.4.1 --- FRPA assay --- p.54 / Chapter 2.6.4.2 --- ABTS + radical cation scavenging activity --- p.55 / Chapter 2.6.5 --- Determination of plasma lipid profiles --- p.55 / Chapter 2.6.5.1 --- Plasma total cholesterol (TC) --- p.55 / Chapter 2.6.5.2 --- Plasma total triglyceride (TG) --- p.56 / Chapter 2.6.5.3 --- Plasma high density lipoprotein cholesterol (HDL-C) determination --- p.57 / Chapter 2.6.5.4 --- Hepatic cholesterol determination by gas chromatography analysis --- p.57 / Chapter 2.7 --- Statistical analysis --- p.59 / Chapter Chapter 3: --- Results and discussion --- p.61 / Chapter 3.1 --- Proximate analysis --- p.61 / Chapter 3.2 --- Small-scale extraction scheme --- p.63 / Chapter 3.2.1 --- Extraction yield --- p.63 / Chapter 3.2.2 --- Antioxidant assays --- p.65 / Chapter 3.2.2.1 --- Hydroxyl free radical scavenging activity --- p.65 / Chapter 3.2.2.2 --- Beta-carotene bleaching method --- p.68 / Chapter 3.2.2.3 --- The formation of TBARS in human LDL oxidation --- p.75 / Chapter 3.2.2.4 --- Total phenolic content (TPC) in DAa and FAa ethanolic and water extracts --- p.81 / Chapter 3.2.2.5 --- Correlation between total phenolic content and antioxidant activity of mushroom extracts --- p.84 / Chapter 3.2.2.6 --- Comparison of antioxidant activity and TPC in DAa and FAa ethanolic and water extracts in the small-scale extraction scheme --- p.88 / Chapter 3.3 --- Large-scale extraction scheme --- p.91 / Chapter 3.3.1 --- Extraction yield --- p.91 / Chapter 3.3.2 --- Antioxidant assays --- p.91 / Chapter 3.3.2.1 --- Hydroxyl free radical scavenging activity --- p.91 / Chapter 3.3.2.2 --- Beta-carotene bleaching method --- p.94 / Chapter 3.3.2.3 --- ABTS + radical cation scavenging activity --- p.96 / Chapter 3.3.2.4 --- Formation of TBARS in human LDL oxidation in the DAa_E_l and Daa_W_1 --- p.97 / Chapter 3.3.2.5 --- Total phenolic content (TPC) of DAa_E_l and DAa_W_l --- p.97 / Chapter 3.3.2.6 --- Correlation between total phenolic content and antioxidant activity --- p.101 / Chapter 3.3.2.7 --- Summary of large-scale extraction scheme --- p.103 / Chapter 3.4 --- In vivo antioxidant activity and hypocholesterolemic effect of DAa studied by animal model --- p.104 / Chapter 3.4.1 --- Effect of DAa´ؤE_1 and DAa_W_l on body weight and food intake --- p.105 / Chapter 3.4.2 --- Effect of DAa一E´ؤ1 and DAa_W_l on plasma total cholesterol (TC) in hamsters --- p.108 / Chapter 3.4.3 --- Effect of DAa´ؤE_1 and DAa W l on plasma total triglycerides (TG) in hamsters --- p.114 / Chapter 3.4.4 --- Effect of DAa_E_l and DAa_W_l on plasma high-density-lipoprotein cholesterol (HDL-C) in hamsters --- p.119 / Chapter 3.4.5 --- Effect of DAa_E_l and DAa一W_1 on hepatic cholesterol (HC) profile in hamsters --- p.124 / Chapter 3.4.6 --- Effect of DAa_E_l and DAa W l on ferric reducing antioxidant power (FRAP) in hamsters (FRAP) --- p.128 / Chapter 3.4.7 --- Effect of DAa_E_l and DAa_W_l on ABTS + cation radical scavenging activity --- p.131 / Chapter 3.4.8 --- The antioxidant activity and hypocholesterolemic effect of DAa extracts --- p.134 / Chapter 3.4.9 --- Summary of in vivo antioxidant activity and hypocholesterolemic effect of DAa studied by animal model --- p.140 / Chapter Chapter 4: --- Conclusions --- p.142 / References --- p.145
165

Evaluation of the anti-diabetic activities of non-starch polysaccharides extracted from the fruiting body of Hericium erinaceus.

January 2005 (has links)
by Li Chi Yeung. / Thesis submitted in: November 2004. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2005. / Includes bibliographical references (leaves 151-176). / Abstracts in English and Chinese. / Thesis Committee --- p.i / Acknowledgement --- p.ii / Abstract (English Version) --- p.iii / Abstract (Chinese Version) --- p.v / Content Page --- p.vii / List of Tables --- p.xiii / List of Figures --- p.xv / Abbreviation --- p.xvii / Chapter Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Diabetes Mellitus --- p.1 / Chapter 1.1.1 --- Epidemiology --- p.1 / Chapter 1.1.2 --- Economic Impact --- p.3 / Chapter 1.2 --- "Digestion, Absorption and Metabolism of Carbohydrates" --- p.4 / Chapter 1.2.1 --- Carbohydrate Digestion --- p.4 / Chapter 1.2.2 --- Carbohydrate Absorption --- p.6 / Chapter 1.2.3 --- Insulin Secretion --- p.6 / Chapter 1.3 --- Pathophysiology of Diabetes Mellitus --- p.7 / Chapter 1.3.1 --- Insulin-Dependent Diabetes Mellitus (lDDM) --- p.7 / Chapter 1.3.1.1 --- Genetics --- p.8 / Chapter 1.3.1.2 --- Autoimmunity --- p.9 / Chapter 1.3.2 --- Non-Insulin-Dependent Diabetes Mellitus (NlDDM) --- p.11 / Chapter 1.3.2.1 --- Insulin Resistance --- p.11 / Chapter 1.3.2.2 --- Impaired Insulin Secretion --- p.14 / Chapter 1.4 --- Management of Diabetes Mellitus --- p.15 / Chapter 1.4.1 --- Sulfonylureas --- p.15 / Chapter 1.4.2 --- Biguanides --- p.16 / Chapter 1.4.3 --- Problems Encountered in the Management of Diabetes --- p.16 / Chapter 1.4.4 --- Role of Dietary Fiber in the Management of Diabetes Mellitus --- p.18 / Chapter 1.4.4.1 --- Dietary Fiber and Gastric Emptying Time --- p.19 / Chapter 1.4.4.2 --- Dietary Fiber and Glucose Absorption in Small Intestine --- p.20 / Chapter 1.4.5 --- Other Natural Products used for Diabetes Treatment…… --- p.22 / Chapter 1.5 --- Mushrooms --- p.22 / Chapter 1.5.1 --- The Definition of Mushrooms --- p.23 / Chapter 1.5.2 --- Nutritional Values of Mushrooms --- p.24 / Chapter 1.5.3 --- Production of Mushrooms --- p.25 / Chapter 1.6 --- Medicinal (Antidiabetic) Properties of Mushrooms --- p.28 / Chapter 1.6.1 --- Ganoderma lucidum --- p.29 / Chapter 1.6.2 --- Tremella aurantia --- p.33 / Chapter 1.6.3 --- Auricularia auricula --- p.36 / Chapter 1.6.4 --- Grifola frondosa --- p.37 / Chapter 1.7 --- Medicinal Uses of Hericium erinaceus --- p.39 / Chapter 1.7.1 --- HeLa Cell Proliferation Inhibitors --- p.39 / Chapter 1.7.2 --- Induction of Growth of Nerve Cells --- p.42 / Chapter 1.7.3 --- Antitumour Activity --- p.42 / Chapter 1.7.4 --- Antidiabetic Effect --- p.43 / Chapter 1.8 --- Objectives --- p.45 / Chapter Chapter 2 --- Materials and Methods --- p.46 / Chapter 2.1 --- Extraction of Polysaccharides from the Fruiting Body of H. erinaceus --- p.46 / Chapter 2.1.1 --- Small-scale Extraction --- p.46 / Chapter 2.1.2 --- Large-scale Extraction --- p.47 / Chapter 2.2 --- Physico-Chemical Characterization of HE-polysaccharides --- p.52 / Chapter 2.2.1 --- Carbohydrate Content: Phenol-Sulfuric Acid Method --- p.52 / Chapter 2.2.2 --- Protein Content: Lowry Assay --- p.52 / Chapter 2.2.3 --- Uronic Acid Content --- p.53 / Chapter 2.2.4 --- Molecular Weight Determination by High Pressure Liquid Chromatography (HPLC) --- p.55 / Chapter 2.2.5 --- Determination of Monosaccharide Composition of Non-Starch Polysaccharides by Gas Chromatography (GC) --- p.56 / Chapter 2.2.5.1 --- Acid Depolymerisation --- p.56 / Chapter 2.2.5.2 --- Neutral Sugar Derivatisation --- p.56 / Chapter 2.2.5.3 --- Determination of Neutral Sugar Composition by Gas Chromatography (GC) --- p.57 / Chapter 2.2.6 --- Structural Study of Polysaccharides by Methylation --- p.59 / Chapter 2.2.6.1 --- Preparation of dry Dimethyl Sulfoxide (DMSO) --- p.59 / Chapter 2.2.6.2 --- Preparation of Methylsulfinyl Methyl Sodium (CH3SOCH2-Na+) from the dry DMSO and Sodium Hydride --- p.59 / Chapter 2.2.6.3 --- Methylation Procedure --- p.60 / Chapter 2.2.6.4 --- Preparation of Partially Methylated Alditol Acetates (PMAAs) --- p.61 / Chapter 2.2.6.5 --- Analysis of the PMAAs by GC --- p.62 / Chapter 2.2.7 --- The Measurement of Viscosity --- p.62 / Chapter 2.3 --- In vitro Hypoglycemic Tests of HE-Polysaccharides --- p.64 / Chapter 2.3.1 --- Glucose Dialysis Retardation Index (GDRl) --- p.64 / Chapter 2.3.1.1 --- Experimental Setup --- p.64 / Chapter 2.3.1.2 --- Measurement of Glucose in the Dialysate --- p.65 / Chapter 2.3.2 --- Inhibition of Amylolysis --- p.66 / Chapter 2.3.2.1 --- Experimental Setup --- p.66 / Chapter 2.3.2.2 --- Measurement of Maltose in the Dialysate --- p.66 / Chapter 2.4 --- In vivo Hypoglycemic Evaluation of HE-Polysaccharides --- p.67 / Chapter 2.4.1 --- Oral Glucose Tolerance Test (OGTT) --- p.67 / Chapter 2.4.2 --- Induction of Type l Diabetes in Normal BALB/c Mice --- p.69 / Chapter 2.4.2.1 --- lnduction Protocol --- p.69 / Chapter 2.4.2.2 --- Measurement of Plasma Glucose Level --- p.70 / Chapter 2.4.3 --- Hypoglycemic Test on Normal and Diabetic BALB/c Mice --- p.71 / Chapter 2.4.4 --- Measurement of Insulin Level by Enzyme-Linked Immunoadsorbent Assay (ELlSA) --- p.72 / Chapter 2.4.4.1 --- Plasma Samples used in ELlSA --- p.72 / Chapter 2.4.4.2 --- Assay Procedure --- p.73 / Chapter 2.5 --- Statistical Evaluation --- p.74 / Chapter Chapter 3 --- Results and Discussion --- p.75 / Chapter 3.1 --- Yield of Polysaccharides extracted from H. erinaceus --- p.75 / Chapter 3.2 --- Physico-chemical Properties of HE Polysaccharides --- p.79 / Chapter 3.2.1 --- "Carbohydrate, Protein and Uronic Acid Content" --- p.79 / Chapter 3.2.2 --- Monosaccharide Compositions --- p.83 / Chapter 3.2.3 --- Molecular Weight of the HE polysaccharides --- p.85 / Chapter 3.2.4 --- Structure of HE polysaccharides --- p.90 / Chapter 3.2.5 --- Conclusion for the Physico-chemical Properties of HE-Polysaccharides --- p.96 / Chapter 3.2.6 --- Viscosity of HE Polysaccharides --- p.99 / Chapter 3.3 --- In vitro Study of the Hypoglycemic Effect of HE-Polysaccharides --- p.101 / Chapter 3.3.1 --- Glucose Dialysis Retardation Index (GDRl) --- p.101 / Chapter 3.3.2 --- Inhibition of α-Amylase Activity --- p.105 / Chapter 3.4 --- In vivo Hypoglycemic Evaluation of HE-Polysaccharides --- p.109 / Chapter 3.4.1 --- In vivo Oral Glucose Tolerance Test (OGTT) in Normal Mice --- p.109 / Chapter 3.4.1.1 --- Oral Glucose Tolerance Test --- p.109 / Chapter 3.4.1.2 --- Effect of Change of Viscosity of HE Polysaccharide in the Gl Tract of Mice --- p.114 / Chapter 3.4.2 --- Establishment of a Diabetic Murine Model --- p.120 / Chapter 3.4.3 --- Hypoglycemic Activity of HE-polysaccharides in Normal Mice --- p.123 / Chapter 3.4.4 --- Hypoglycemic Activity of HE-polysaccharides in Diabetic Mice --- p.126 / Chapter 3.4.5 --- Change of Plasma Insulin Level in the Hypoglycemic Test --- p.132 / Chapter 3.4.6 --- Comparison of Hypoglycemic Activity of HE-Polysaccharides in Normal and Diabetic mice --- p.139 / Chapter 3.4.6.1 --- Severity of Diabetic Conditions lnduced --- p.139 / Chapter 3.4.6.2 --- Change in Insulin Secretion --- p.140 / Chapter 3.4.6.3 --- Glucose Transporter --- p.140 / Chapter 3.5 --- Other Factors that Affect in vivo Hypoglycemic Activity of the HE-polysaccharides --- p.141 / Chapter 3.5.1 --- Route of Administration: Oral Feeding and Intraperitoneal Injection --- p.141 / Chapter 3.5.2 --- Molecular Mechanisms of Hypoglycemic Activity --- p.142 / Chapter 3.5.3 --- Glucose Toxicity --- p.144 / Chapter 3.5.3.1 --- Insulin Resistance --- p.144 / Chapter 3.5.3.2 --- Impaired Insulin Secretion --- p.145 / Chapter Chapter 4 --- Conclusions and Future Works --- p.147 / References --- p.151
166

Mushroom sclerotia: a novel source of dietary fiber for enhancing passive calcium absorption in the large intestine. / CUHK electronic theses & dissertations collection

January 2004 (has links)
by Wong Ka-Hing. / "September 2004." / Thesis (Ph.D.)--Chinese University of Hong Kong, 2004. / Includes bibliographical references (p. 226-279). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web. / Abstracts in English and Chinese.
167

Utiliza??o de pel?cula de f?cula de mandioca e ?leo de canela na conserva??o p?s-colheita de tomate cereja / Use of cassava starch film and cinnamon oil in postharvest conservation of cherry tomato

OLIVEIRA, Cristiana Maia de 23 July 2013 (has links)
Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2018-11-12T20:55:15Z No. of bitstreams: 1 2013 - Cristiana Maia de Oliveira.pdf: 2253824 bytes, checksum: 0c49afa03412e03e8ba8d8d9e8b01029 (MD5) / Made available in DSpace on 2018-11-12T20:55:15Z (GMT). No. of bitstreams: 1 2013 - Cristiana Maia de Oliveira.pdf: 2253824 bytes, checksum: 0c49afa03412e03e8ba8d8d9e8b01029 (MD5) Previous issue date: 2013-07-23 / CNPq / The tomato has been widely cultivated in the state of Rio de Janeiro mainly by smallholders and family farmers that make use of organic agriculture as a way to add value to the culture. After harvest, the tomato presents itself as a highly perishable fruit, being a climacteric fruit, the ripening involves a number of changes in it physical and chemical characteristics. The main goal of this work was to evaluate the conservation and postharvest quality of cherry tomatoes Perinha ?gua Branca and Mascot cultivars, stored at room and controlled conditions. Three experiments were carried out: 1) postharvest longevity of fruits cherry tomato, 2) evaluation of the effect of cassava starch film on postharvest quality of fruits and 3) use of cinnamon essential oil to control pathogens. We carried out the following physico-chemical analyzes: weight loss, color, pH, titratable acidity, soluble solids, ascorbic acid and pectin methyl esterase activity. In the first experiment, we used fruits in the intermediate, pinky, red and mature stages to both cultivars. At room temperature, the post-harvest longevity of fruits in Perinha cultivar was 20 days in the pinky and 15 days to red and mature stages. ?Mascot? longevity was 24 days to the intermediate stage, 20 days for pinky and 15 days to red and mature stage. In controlled temperature postharvest longevity of fruits in Perinha cultivar was 24 days in the intermediate and pinky stages, 20 days to red and 15 days to mature. ?Mascot? longevity was 27 days in the intermediate and pinky stages, 24 days to red and to mature. In the second experiment, was used cassava starch coating in the following concentrations: 1%, 3% and 5%. It was observed that at room and controlled conditions cassava starch coating at a concentration of 3% promoted the best results, delaying the ripening and senescence while maintaining fruit quality. The concentration of 1% was similar to the control almost all the experimental period, while starch coating at 5% prevented the normal maturation process and showed high levels of infected fruits by fungi which affect the appearance and quality. The average activity of PME was higher in ?Mascot? fruits. The third experiment consisted in a combination of distilled water and starch coating at 3% associated with 0.1% and 0.3% concentrations of cinnamon essential oil. The cinnamon essential oil made changes on the fruit surface, causing stains and burns affecting the fruit quality. The oil was not effective in diseases control. / O tomate cereja vem sendo amplamente cultivado no Estado do Rio de Janeiro principalmente por pequenos produtores e pela agricultura familiar que fazem uso da agricultura org?nica como forma de agregar valor a cultura. O tomate ap?s a colheita apresenta-se como um fruto altamente perec?vel, sendo um fruto climat?rico seu amadurecimento acarreta uma s?rie de transforma??es em suas caracter?sticas f?sicas e qu?micas. Este trabalho teve por objetivo avaliar a conserva??o e qualidade p?s-colheita de tomates cereja cultivares Perinha ?gua Branca e Mascot, armazenados em condi??es ambiente e controlada. Foram realizados tr?s experimentos: 1) longevidade p?s-colheita de frutos de tomate cereja; 2) Avalia??o do efeito da pel?cula de f?cula de mandioca na qualidade p?s-colheita e 3) utiliza??o de ?leo essencial de casca de canela no controle de podrid?es. Foram realizadas as seguintes an?lises f?sicas e qu?micas: perda de massa fresca, cor, pH, acidez total titul?vel, s?lidos sol?veis, ?cido asc?rbico e atividade de pectinametilesterase. No experimento 1 foram utilizados frutos nos est?dios de vez, rosado, vermelho e maduro de ambas as cultivares. Em ambiente controlado, a longevidade p?s-colheita dos frutos da cultivar Perinha foi de 20 dias para os est?dios de vez e rosado e 15 dias para vermelho e maduro. Para ?Mascot? a longevidade foi de 24 dias para o est?dio de vez, 20 dias para rosado e 15 dias para vermelho e maduro. Em temperatura controlada, a longevidade p?s-colheita dos frutos da cultivar Perinha foi de 24 dias para de vez e rosado, 20 dias para vermelho e 15 dias para maduro. Para ?Mascot? a longevidade foi de 27 dias para de vez e rosado e 24 dias para vermelho e maduro. No experimento 2 foram utilizados revestimentos de f?cula de mandioca nas concentra??es de 1%, 3% e 5%. Foi observado que em condi??es ambiente e controlada, o revestimento de f?cula de mandioca na concentra??o de 3% foi o que promoveu melhores resultados retardando o processo de amadurecimento e senesc?ncia al?m de manter a qualidade dos frutos. A concentra??o de 1% se assemelhou ao controle durante quase todo per?odo experimental, enquanto que f?cula 5% impediu o processo normal de amadurecimento e mostrou alto ?ndice de frutos infectados por fungos comprometendo a apar?ncia e qualidade. A atividade m?dia de PME foi maior nos frutos de ?Mascot?. O experimento 3 consistiu da combina??o ?gua destilada e f?cula 3% associada a concentra??es de 0,1% e 0,3% de ?leo essencial de canela. O ?leo essencial de casca de canela promoveu altera??es na superf?cie dos frutos, provocando manchas e queimaduras afetando sua qualidade. O ?leo n?o foi efetivo no controle de podrid?es.
168

Material Processing for Edible Electronics

January 2019 (has links)
abstract: A new type of electronics was envisioned, namely edible electronics. Edible electronics are made by Food and Drug Administration (FDA) certified edible materials which can be eaten and digested by human body. Different from implantable electronics, test or treatment using edible electronics doesn’t require operations and perioperative complications. This dissertation bridges the food industry, material sciences, device fabrication, and biomedical engineering by demonstrating edible supercapacitors and electronic components and devices such as pH sensor. Edible supercapacitors were fabricated using food materials from grocery store. 5 of them were connected in series to power a snake camera. Tests result showed that the current generated by supercapacitor have the ability to kill bacteria. Next more food, processed food and non-toxic level electronic materials were investigated. A “preferred food kit” was created for component fabrication based on the investigation. Some edible electronic components, such as wires, resistor, inductor, etc., were developed and characterized utilizing the preferred food kit. These components make it possible to fabricate edible electronic/device in the future work. Some edible electronic components were integrated into an edible electronic system/device. Then edible pH sensor was introduced and fabricated. This edible pH sensor can be swallowed and test pH of gastric fluid. PH can be read in a phone within seconds after the pH sensor was swallowed. As a side project, an edible double network gel electrolyte was synthesized for the edible supercapacitor. / Dissertation/Thesis / Doctoral Dissertation Chemical Engineering 2019
169

Peroxide value and trans analyses by Fourier transform infrared (FTIR) spectroscopy

Ma, Kangming, 1965- January 2000 (has links)
No description available.
170

Characteristics of Australian edible fungi in the genus Lepista and investigation into factors affecting cultivation

Stott, Karen Gai, University of Western Sydney, Hawkesbury, Faculty of Science and Technology, School of Science, Food and Horticulture January 1998 (has links)
This thesis focuses on the edible fungus Lepista (Pied Bleu or Wood Blewit). Factors affecting its potential commercial cultivation were explored and a contribution to knowledge of the morphology and cultivation of Australian species of Lepista has been made. Australian collections of Lepista were made within a 200 km zone of Sydney. A study of the morphology and taxonomic species of these collections was undertaken. Intra- and inter-fertility crosses were completed with French L. nuda and L. sordida to determine genetic relationships and biological species. Suitable substrates for agar medium, spawn production and cultivation were explored. The response to temperature of French and Australian Lepista in vitro, and Australian Lepista under cultivation, using cold shock, was observed. The effect of modified atmosphere exchanges per hour, CO2 levels, and cold shock during the cultivation cycle and sporophore production were investigated. A genebank of Australian Lepista was established. Three species of Lepista were found in Australia : L. nuda, L. sordida and L. saeva. Two other groups of Lepista were identified. The use of A. bisporus compost appeared to be optimal for experimental and commercial applications. Australian isolates of Lepista tolerate higher temperatures than French isolates, and grew at double the rate of the French at all temperatures except 5 degrees centigrade. The length of the spawn run was reduced from 43-58 days to 12-16 days with introduced CO2 of 9,000-11,000 ppm, but an erratic cyclic pattern of net CO2 production occurred which could only be stabilised by increasing ventilation. This initial cyclic pattern appeared to inhibit subsequent sporophore formation. / Doctor of Philosophy (PhD)

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