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

Sulfur Amino Acid Requirements and the Bioavailability of Oxidized Sulfur Amino Acids in the Growing Rat Fed Eight Percent Dairy Protein

Peace, Robert William 07 1900 (has links)
No description available.
12

Wet-processing of low-protein hard winter wheat flour to improve its breadmaking potential

Wu, Yangsheng. January 1985 (has links)
Call number: LD2668 .T4 1985 W8 / Master of Science
13

Economic feasibility of segregating grain by protein concentration while harvesting

Martin, Charles T. (Charles Tyler) 14 June 2012 (has links)
Price premiums and discounts are currently paid for various classes of wheat in the US marketplace. These premiums and the known heterogeneity of grain protein across landscapes beg the question of whether grain could be separated on the farm to maximize revenues. Theoretically, the concavity or convexity of a price function defines if an opportunity to segregate grain exists. Although this is true, prices in the market place are paid in stepped increments, which result in unique revenue maximizing solutions. This study was conducted to determine the economic feasibility of segregating wheat by protein content on the combine harvester during harvest. Both web-based and spreadsheet calculators were built to predict the best point in which to segregate a crop at, as well as define the protein level and quantity of each segregated volume of grain. The costs of segregation vary by operation, but fixed, variable, and opportunity costs are estimated to total $0.1739 bu⁻¹ if segregation is used every year. Revenue gains varied with the price schedule, field mean protein value, and the standard deviation of protein. Revenue gains increased in proportion to the size of a price step in a price schedule. Soft white winter wheat showed the greatest potential for segregation; however, on average yearly expected premiums are less than $.05 bu⁻¹, well below total variable costs. Price schedules occur which allow for profits of over $1.00 bu⁻¹ from segregation, although these are not the norm. Historically, on-combine grain segregation would not be economically feasible for the average producer. However, under certain supply and demand conditions, premiums occur that would make on-combine grain segregation profitable. Individuals will have to evaluate the feasibility on a case-by-case basis. / Graduation date: 2013
14

Criação de Tilápia-do-Nilo, Oreochromis niloticus, em Tanques-rede, na Usina Hidrelétrica de Chavantes, Rio Paranapanema, SP/PR

Ayroza, Luiz Marques da Silva [UNESP] 17 February 2009 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:30:31Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-02-17Bitstream added on 2014-06-13T20:21:13Z : No. of bitstreams: 1 ayroza_lms_dr_jabo.pdf: 295423 bytes, checksum: de4036c8ed2e29b2baed4a16511f9a37 (MD5) / A criação de tilápia-do-nilo, O. niloticus, em tanques-rede vem se expandindo em ritmo acelerado, utilizando-se densidades de estocagem com dependência da alimentação artificial e da renovação da água. Foram utilizados 36.000 peixes, da variedade Chitralada, sexualmente revertidos, onde avaliou-se diferentes densidades de estocagem (100, 200, 300 e 400 peixes m-3) e níveis protéicos da ração (28 e 32% PB), na fase de terminação (Fase 2), distribuídos em 24 tanques-rede, no reservatório da UHE de Chavantes, Rio Paranapanema SP/PR. Foram avaliadas duas produções de inverno, com médias de peso iniciais de 288,19 ± 64,21 g até atingirem peso comercial de 662,59 ± 102,73 g, nos meses de abril a julho de 2005 (103 dias) e de 2006 (95 dias). Os experimentos foram conduzidos em blocos inteiramente casualizados (fatorial) e seis repetições. Foram estimados os valores dos índices zootécnicos, ganho em peso diário (GPD), ganho em biomassa (GB), conversão alimentar aparente (CAA) e sobrevivência (S). Ocorreu efeito quadrático com diminuição dos valores do GPD e o crescente aumento do número de peixes adensados (p=0,0022). Os valores de GPD utilizando-se a ração com 32% PB foram significativamente superiores aos de 28% PB (p=0,0329). Houve interação entre os fatores densidade de estocagem e porcentagem de proteína na ração (p=0,0318) no índice de sobrevivência. Para os valores de CAA e GB não ocorreram interações entre as porcentagens de PB e densidade de estocagem (DE) (p=0,1157; 0,4058). Ocorreu efeito quadrático com os aumentos nos valores da CAA X DE (p=0,0210) e GB X DE (p=0,0002). Conclui-se que, os maiores valores de GPD mostraram que a ração de 32%PB e a densidade de 100 peixes m-3 são as mais indicadas foram as mais indicadas para essa fase de criação. / The Nile Tilapia, O. niloticus, breeding in net cages has been growing faster, uses high stocking densities, depending on artificial diet and water renewal. There were allocated 36.000 fish of the Chitralada variety, sexually reverted, where stocking densities (100, 200, 300, and 400 m³) and food protein level (28 and 32% CP) were evaluated in (phase 2), distributed in 24 net cages, in the Chavantes HPS Reservoir, Paranapanema River, SP/PR. Two winter crops were evaluated, using fish with 288,19 ± 64,21g initial mean weight up to reaching market weight of 662,59 ± 102,73g, in months of April to July 2005 (103 days) and 2006 (95 days). The experiments were carried out in entirely randomized blocks (factorial) and six replicates. The following zootechnical indexes values were studied, daily weight gain (DWG), biomass gain (BG), food conversion rate (FCR) and survival (S). Was a quadratic effect with the decrease of the DWG values and the increasing augment on the added up fish number (p=0,0022). The DWG values, using 32% CP food were significantly superior to the DWG with 28% CP food (p=0,0329). There was interaction between the stocking density and food protein percentage (p= 00,318) in the survival index. For the values of parameter FCR and BG, there were no interactions between the protein percentage in the food and stocking density (SD) (p=0,1157; 0,4058). There was a quadratic effect with the increases in the FCR X SD values (p=0,0210) and BG X SD (p=0,0002). Concluded that, the higher DWG showed that the 32% CP foodstuff and the 100 fish m-3 was the most appropriate for this phase of rearing.
15

Propriedades nutritivas e funcionais fisiológicas de algumas proteínas alimentícias / Nutritional and physiological functional properties of some food proteins

Jacobucci, Helaine Beatriz 17 August 2018 (has links)
Orientador: Valdemiro Carlos Sgarbieri / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-17T02:46:39Z (GMT). No. of bitstreams: 1 Jacobucci_HelaineBeatriz_D.pdf: 1129830 bytes, checksum: 37cb3d4735acb6b02966f93620559d37 (MD5) Previous issue date: 2010 / Resumo: Com o propósito de melhor harmonizar os vários aspectos pesquisados, a tese está apresentada em quatro capítulos. No primeiro capítulo se fez um apanhado geral dos aspectos químicos, nutricionais e funcionais (tanto tecnológicos como os fisiológicos) das fontes protéicas estudadas no decorrer do trabalho e descritos na literatura. No segundo capítulo estudou-se o poder imunoestimulante de uma caseína comercial (CC), da caseína isolada na forma de micelas íntegras (CM), de um isolado de proteína de soja comercial (IPS), um concentrado de globulinas (BSG) e um concentrado de albumina (BSA), isolados do soro de sangue bovino, um isolado protéico de soro de leite bovino (NZ), importado da Nova Zelândia, um isolado de soro de leite bovino produzido em planta piloto, em Rennes (Ren), França, e um concentrado de proteínas de soro de leite bovino (CSD), produzido em planta piloto (Tecnolat), ITAL, Campinas. A imunoestimulação foi medida no baço pelo processo de contagem de células formadoras de placa (CFP) após imunização de camundongos da linhagem A/Uni, com 5 x 106 hemáceas de carneiro. A formação de placas (reação antígeno-anticorpo) foi medida por contagem de células formadoras de placa com auxílio de um microscópio de fase e de uma lupa. O número de CFP, que representa a intensidade da reação antígeno-anticorpo foi expresso para o órgão todo (CFP/baço x 10-3). Foram estudados neste capítulo o poder imunoestimulante sobre as células de baço das várias proteínas, as influências da concentração da proteína na dieta, a combinação do CSD com as outras preparações protéicas e a influência de diferentes tratamentos (processamentos) sobre a imunoestimulação. Concluiu-se que o concentrado de soro de leite bovino produzido no ITAL, Campinas, foi o que apresentou maior poder imunoestimulante e que a imunoestimulação, para esse preparado, manteve-se na faixa de concentração de 7,5 a 20g de proteína/100g de dieta. Todas as fontes de proteína estudadas quando associadas (misturadas) ao CSD na dieta, influíram negativamente no poder imunoestimulante do CSD, exceto a BSA. Tratamentos térmicos acima de 50°C, exceto a pasteurização (72°C, 15 seg.) e a irradiação acima de 3KG influíram negativamente sobre o poder imunoestimulatório do CSD. A desidratação do concentrado em ¿Spray dryer¿ não afetou significativamente o poder de imunoestimulação do CSD. No terceiro capítulo procurou-se estudar as influências da composição em aminoácidos dos materiais protéicos, CSD, caseína, hidrolisado enzimático da caseína e, conseqüentemente, do estado de estruturação dessas proteínas, no consumo de dieta, ganho de peso corporal, proteínas sanguíneas e estímulo à síntese de glutationa, no fígado. No quarto capítulo realizou-se uma avaliação nutricional e imunológica de quatro dietas de composição básica semelhante, variando-se apenas o componente protéico. As dietas estudadas foram, uma fórmula comercial tomada como referência (FC), uma dieta à base de caseína micelar (CM), outra à base de CSD e finalmente uma mistura 50:50 CSD/CM. Para a avaliação do estímulo imunológico utilizaram-se camundongos da linhagem A/Uni com 6-8 semanas de idade e a técnica de imunoestimulação com injeção de hemáceas de carneiro (5 x 106 células), seguido da determinação do número de células formadoras de placa (CFP), contadas em suspensão de células de baço de animais, cinco dias após imunização. As CFP representam reações antígenoanticorpo, anticorpos que representam a imunoglobulina M (IgM), reação imune primária em resposta ao imunógeno das hemáceas de carneiro. Os resultados da imunoestimulação foram mais baixos para a dieta CM, mais elevados para as dietas CSD e FC e intermediários para CM/CSD (50:50). Estatisticamente não houve diferença entre as dietas CSD e FC nem entre CSD/CM e FC (p > 0,05), porém houve diferença estatística em favor da dieta CSD em relação à CM e CSD/CM (p < 0,05). Em relação ao poder de estímulo à glutationa, a dieta CSD revelou maior concentração hepática (8,02 ??0,59 ?moles/g de tecido). Não houve diferença estatística para glutationa entre FC e CSD/CM (6,55 ??0,96 ?moles/g de tecido) de glutationa hepática. Demonstrou-se uma correlação altamente positiva (CPF = 3,3395 + 9,0913 x GSH, r = 0,94) entre os estímulos à síntese de IgM (baço) e de GSH (fígado). Os parâmetros nutricionais consumo de dieta, ganho de peso, quociente de eficiência alimentar (QEA), digestibilidade aparente da proteína (Dap%), valor biológico aparente (VBap%), balanço de nitrogênio (BN) e quociente de eficiência protéica (PER), foram todos bastante elevados e não diferiram entre os tratamentos (p > 0,05). Tomados no todo, os resultados confirmam que, elevados valores nutricionais podem não representar elevadas propriedades funcionais-fisiológicas, avaliados nesta pesquisa como poder imunomodulador e estímulo à síntese de glutationa / Abstract: With the purpose of better harmonize the various aspects studied in this thesis, it was organized in four chapters. The first chapter consisted of an overview of the chemical nutritional and functional (technologic and physiologic) properties of the protein sources studied in this thesis, utilizing data from recent literature. The main objective of the second chapter was to comparatively demonstrate the immunestimulating power of various protein systems of food origen, including: a commercial casein preparation (CC), a casein isolated in pilot plant in the form of whole micelles (CM), a commercial soy protein isolate (SPI), a bovine serum albumin (BSA) and a bovine serum globulin (BSG) isolated in laboratory from bovine serum, a bovine whey protein isolate (NZ) imported from New Zealand, a bovine whey protein isolate produced in Pilot plant in Rennes (Ren), Rennes France, a bovine whey protein concentrate (WPC) produced in Pilot Plant, ITAL, Campinas. The immunestimulation was measured in spleen cells by counting Plaque Forming Cells (PFC) using A/Uni mice after immunization with sheep red blood cells (SRBC = 5 x 106 cells). The Plaque (antigen-antibody reaction) was quantified in spleen cell suspensions by using a phase microscope and a lup. The number of plaque forming cells (PFC) was considered for the whole spleen and expressed as (PFC/spleen x 10-3). The immunestimulating power on the spleen cells was studied for various protein sources. The influence of dietary protein concentration, the combination of WPC with other protein preparations and the influence of various treatments on the protein was also studied. It was conclude that the whey protein concentrate produced in ITAL (WPC) presented the highest immunestimulating power, that the immunestimulation for this preparation remained constant in the range of concentration 7.5 to 20g protein/100g diet, that all the protein sources studied, when mixed with WPC in the diet, showed a negative influence on the immunestimulating power of WPC alone. Heat treatment (>50°C), except pasteurization (72°C, 15 seg), and gamma-irradiation above 3KG, had a negative influence on the immunestimulation by WPC. The dehydration of the WPC by spray drying did not significantly affect the immunestimulation by WPC. The third chapter aimed at studying the influence of amino acid composition (WPC, CC, and CC-hidrolysates) and, consequently of the structural state of the casein molecules, in the diet consumption, body weight gain, blood protein profile, and on liver glutathione synthesis stimulation. The fourth chapter consists of the nutritional and immunological evaluation of four protein diets (CF, WPC, WPC:CM (50:50) and CM alone) in an otherwise similar composition. For the immunological property, A/Uni mice with 6-8 weeks of age, immunestimulated with sheep red blood cells (SRBC), 5 x 106 cells, following determination of the number of plaque forming cells (PFC) 5 days after immunization was used. PFC number indicates the antigen-antibody reaction between the SRBC-antigen and immunoglobulin M formed by the spleen cells. PFC was lowest for CM protein diet, highest for the WPC and CF diets and intermediate for CM/WPC (50:50) diet. No statistic difference was measured between WPC and CF or between WPC/CM and CF (p > 0.05), however there was statistic difference (p < 0.05) in favour of WPC, compared with CM and WPC/CM (50:50) (p < 0.05). Regarding glutathione stimulation, the WPC diet showed the highest activity (8.02 ± 0.59 µmoles GSH/g tissue). No statistic difference was shown between the CF and WPC/CM diets (6.55 ± 0.96 µmoles/g) for liver glutathione. A very strong positive correlation (CPF = 3.3395 + 9.0913 x GSH, r = 0.94) between spleen CPF counting (spleen IgM) and liver GSH, was demonstrated for the WPC protein diet. The nutritional parameters such as diet consumption body weight gain, diet efficiency ratio (QEA), apparent protein digestibility (Dap%), protein apparent biological value (BVap%), nitrogen balance (NB), and protein efficiency ratio (PER), they were all high but did not show statistic difference among them (p > 0.05). Considering all data this work confirm that protein nutritive value may not represent high functional properties, in this research applied to the immunestimulation and GSH biosynthesis / Doutorado / Nutrição Experimental e Aplicada à Tecnologia de Alimentos / Doutor em Alimentos e Nutrição
16

Nutritional evaluation of selected Hong Kong seaweeds as well as their protein concentrates.

January 2000 (has links)
by Wong Ka Hing. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2000. / Includes bibliographical references. / Abstracts in English and Chinese. / Dedication --- p.i / Thesis committee --- p.ii / Acknowledgements --- p.iii / Abstract --- p.iv / Abstract (Chinese version) --- p.vi / Table of contents --- p.viii / List of tables --- p.xv / List of figures --- p.xviii / List of abbreviation --- p.xix / Chapter Chapter one: --- General introduction / Chapter 1.1. --- Definition --- p.1 / Chapter 1.2. --- Classification --- p.2 / Chapter 1.3. --- Potential food use of seaweeds --- p.7 / Chapter 1.4. --- Hong Kong seaweeds --- p.10 / Chapter 1.5. --- Sargassum species --- p.12 / Chapter 1.6. --- Hypnea species --- p.13 / Chapter 1.7. --- Ulva species --- p.14 / Chapter 1.8. --- Design of research project --- p.15 / Chapter Chapter two: --- "Effect of diflerent drying methods on proximate composition, amino acid profile and some physico-chemical properties of brown seaweeds, Sargassum hemiphyllum, Sargassum henslowianum and Sargassum patens" / Chapter 2.1. --- Introduction --- p.20 / Chapter 2.2. --- Materials and methods --- p.23 / Chapter 2.2.1. --- Sample preparation --- p.23 / Chapter 2.2.2. --- Proximate analysis --- p.26 / Chapter 2.2.2.1. --- Crude protein content --- p.26 / Chapter 2.2.2.2. --- Ash content --- p.26 / Chapter 2.2.2.3. --- Total dietary fiber (TDF) content --- p.27 / Chapter 2.2.2.4. --- Crude lipid content --- p.28 / Chapter 2.2.2.5. --- Carbohydrate content --- p.29 / Chapter 2.2.2.6. --- Moisture analysis --- p.29 / Chapter 2.2.3. --- Amino acid analysis --- p.30 / Chapter 2.2.3.1. --- "Amino acids excluding cystine, methionine and tryptophan" --- p.30 / Chapter 2.2.3.2. --- Cystine and methionine --- p.31 / Chapter 2.2.4. --- Physico-chemical properties --- p.32 / Chapter 2.2.4.1 --- Swelling capacity (SWC) --- p.32 / Chapter 2.2.4.2. --- Water holding capacity (WHC) --- p.32 / Chapter 2.2.4.3. --- Oil holding capacity (OHC) --- p.33 / Chapter 2.2.5. --- Statistical analysis --- p.34 / Chapter 2.3. --- Results and discussion --- p.34 / Chapter 2.3.1. --- Proximate composition --- p.34 / Chapter 2.3.2. --- Amino acid composition --- p.39 / Chapter 2.3.3. --- Physico-chemical properties --- p.42 / Chapter 2.3.4. --- Conclusions --- p.46 / Chapter Chapter three: --- "Effect of different methods on protein extarctability, in vitro protein digestibility and amino acid profile of seaweed protein concentrates isolated from brown seaweeds, Sargassum hemiphyllum, Sargassum henslowianum and sargassum patens" / Chapter 3.1. --- Introduction --- p.48 / Chapter 3.2. --- Materials and methods --- p.51 / Chapter 3.2.1. --- Sample preparation --- p.51 / Chapter 3.2.2. --- Extraction of seaweed protein concentrates --- p.51 / Chapter 3.2.3. --- Precipitation of seaweed protein concentrates --- p.52 / Chapter 3.2.4. --- Crude protein content analysis --- p.53 / Chapter 3.2.5. --- Extraction of total phenolic compounds --- p.53 / Chapter 3.2.6. --- Determination of total phenolic compounds --- p.54 / Chapter 3.2.7. --- In vitro protein digestibility --- p.55 / Chapter 3.2.8. --- Amino acid analysis --- p.56 / Chapter 3.2.9. --- Statistical analysis --- p.56 / Chapter 3.3. --- Results and discussion --- p.56 / Chapter 3.3.1. --- Effect of oven- or freeze-drying on protein extractability from seaweeds --- p.57 / Chapter 3.3.1.1. --- Total crude protein and total phenolic content in seaweeds --- p.57 / Chapter 3.3.1.2. --- "%Nitrogen, %protein, sample dry weight, amount of protein extracted and %yield of PCs" --- p.60 / Chapter 3.3.2. --- Effect of oven- and freeze-drying on protein quality of seaweed PCs --- p.62 / Chapter 3.3.2.1. --- Total phenolic content and in vitro protein digestibility of seaweed PCs --- p.62 / Chapter 3.3.2.2. --- Amino acid composition --- p.64 / Chapter 3.3.3. --- Conclusions --- p.67 / Chapter Chapter four: --- "Proximate composition, amino acid profile and some physico- chemical properties of some red (Hypnea charoides and Hypnea japonica) and green seaweeds (Ulva lactuca)" / Chapter 4.1. --- Introduction --- p.68 / Chapter 4.2. --- Materials and methods --- p.71 / Chapter 4.2.1. --- L Sample preparation --- p.71 / Chapter 4.2.2. --- Proximate analysis --- p.71 / Chapter 4.2.3. --- Amino acid profile --- p.73 / Chapter 4.2.4. --- Physico-chemical properties --- p.73 / Chapter 4.2.5. --- Statistical analysis --- p.74 / Chapter 4.3. --- Results and discussion --- p.74 / Chapter 4.3.1. --- Proximate composition --- p.74 / Chapter 4.3.2. --- Amino acid composition --- p.78 / Chapter 4.3.3. --- Physico-chemical properties --- p.81 / Chapter 4.3.4. --- Conclusions --- p.86 / Chapter Chapter five: --- In vitro protein digestibility and amino acid profile of seaweed protein concentrates isolated from some red (Hypnea charoides and Hypnea japonica) and green seaweeds (Ulva lactuca) / Chapter 5.1. --- Introduction --- p.88 / Chapter 5.2. --- Materials and methods --- p.89 / Chapter 5.2.1. --- Sample preparation --- p.89 / Chapter 5.2.2. --- Extraction and precipitation of seaweed PCs --- p.90 / Chapter 5.2.3. --- Crude protein analysis --- p.90 / Chapter 5.2.4. --- Extraction and determination of total phenolic contents --- p.90 / Chapter 5.2.5. --- In vitro protein digestibility --- p.91 / Chapter 5.2.6. --- Amino acid analysis --- p.92 / Chapter 5.2.7. --- Statistical analysis --- p.92 / Chapter 5.3. --- Results and discussion --- p.93 / Chapter 5.3.1. --- Protein extractability --- p.93 / Chapter 5.3.1.1. --- Crude protein and total phenolic contentin seaweeds --- p.93 / Chapter 5.3.1.2. --- "%Nitrogen, %protein, sample dry weight, amount of protein extracted and %yield of PCs" --- p.95 / Chapter 5.3.2. --- Protein quality --- p.97 / Chapter 5.3.2.1. --- Total phenolic content and in vitro protein digestibility of seaweed PCs --- p.97 / Chapter 5.3.2.2. --- Amino acid composition --- p.99 / Chapter 5.3.3. --- Conclusions --- p.103 / Chapter Chapter six: --- Biological evaluation on protein quality of seaweed protein concentrates isolated from Hypnea charoides and Hypnea japonica / Chapter 6.1. --- Introduction --- p.104 / Chapter 6.2. --- Materials and methods --- p.114 / Chapter 6.2.1. --- Sample preparation --- p.114 / Chapter 6.2.2. --- Extraction and precipitation of seaweed protein concentrates --- p.114 / Chapter 6.2.3. --- Diet preparation --- p.115 / Chapter 6.2.4. --- Rat bioassay --- p.117 / Chapter 6.2.5. --- Biological indices --- p.118 / Chapter 6.2.6. --- Statistical analysis --- p.119 / Chapter 6.3. --- Results and discussion --- p.119 / Chapter 6.3.1. --- Protein quality of seaweed PCs --- p.119 / Chapter 6.3.2. --- Weight of major organs --- p.126 / Chapter 6.3.3. --- Conclusions --- p.129 / Chapter Chapter seven: --- Functional properties of protein concentrates isolated from Hypnea charoides and Hypnea japonica / Chapter 7.1. --- Introduction --- p.130 / Chapter 7.2. --- Materials and methods --- p.136 / Chapter 7.2.1. --- Sample preparation --- p.136 / Chapter 7.2.2. --- Preparation of protein concentrates --- p.137 / Chapter 7.2.3. --- Nitrogen solubility --- p.137 / Chapter 7.2.4. --- Water and oil holding capacity --- p.138 / Chapter 7.2.5. --- Viscosity --- p.139 / Chapter 7.2.6. --- Emulsifying activities and emulsion stability --- p.140 / Chapter 7.2.7. --- Foam capacity and foam stability --- p.141 / Chapter 7.2.8. --- Statistical analysis --- p.142 / Chapter 7.3. --- Results and discussion --- p.142 / Chapter 7.3.1. --- Nitrogen solubility --- p.142 / Chapter 7.3.2 --- Wafer and oil holding capacity --- p.145 / Chapter 7.3.3. --- Viscosity --- p.147 / Chapter 7.3.4 --- Emulsifying activities and emulsion stability --- p.149 / Chapter 7.3.5. --- Foam capacity and foam stability --- p.153 / Chapter 7.3.6. --- Conclusions --- p.157 / Chapter Chapter 8: --- Conclusions --- p.158 / References --- p.160 / Appendix --- p.195 / Related publications --- p.202
17

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.
18

Development of a method to measure protein in red wines : a survey of protein, mannan and tannin in Pinot noir wines

Smith, Mark R. (Mark Robert) 24 August 2010 (has links)
A number of methods to isolate and quantify protein in Pinot noir wines were evaluated. The combination of precipitation by acetone containing 10% w/v trichloroacetic acid followed by quantification with the Bradford assay, reported in yeast invertase equivalents yielded the most accurate results when compared to micro-Kjeldahl analysis. The technique was validated by dialysis and proteolysis experiments and was used to assay protein in 57 Pinot noir wines. These wines were found to contain protein concentrations ranging from 49 to 102 mg/L. The mannan and tannin content of the wines was also measured, but no correlation between protein content and concentrations of these components was found. The presence of protein in red wines greater than 30 years old at concentrations typically found in white wines contradicts the notion that interactions with tannin severely reduce protein levels. / Graduation date: 2011
19

Quantitative genetic analysis of agronomic and kernel endosperm traits in quality protein maize (QPM) and investigations of the putative nutritional value of contaminated QPM crops.

Machida, Lewis. January 2008 (has links)
The importance of maize in sub-Saharan Africa and the potential of quality protein maize (QPM) to alleviate the nutritional gap caused by lack of access to adequate protein rich foods were highlighted. Frustrations from complex inheritance systems of the QPM trait leading to calls for more information on the inheritance and stability of the QPM trait, fear of total loss of the QPM trait due to the recessive nature of the opaque-2 gene to the wild type gene in normal endosperm maize when QPM and normal endosperm maize coexist, lack of information on the nutritional value of contaminated QPM grain, and poor linkages with the smallholder farmers were all cited as drawbacks in the promotion and adoption of QPM. Therefore the objectives of the study were: 1) To solicit the participation of smallholder farmers in the development and setting up of QPM breeding goals, objectives and dissemination strategies; 2) To estimate general combining ability (GCA), specific combining ability (SCA) and reciprocal cross effects on anthesis days, quality traits and grain yield among the publicly available elite QPM inbred lines; 3) To compare experimental QPM hybrids with selected check cultivars, and normal endosperm maize hybrids for grain yield performance and kernel endosperm modification scores; 4) To evaluate QPM hybrids for grain yield and kernel endosperm modification scores in selected sub-Saharan Africa target environments. 5) To determine the level of normal endosperm maize pollen contamination that can occur in quality protein maize without loss of nutritional superiority; 6) To estimate the average levels and the patterns of foreign maize pollen contamination in QPM crops coexisting with normal endosperm maize varieties. The contribution of smallholder farmers in setting breeding goals and dissemination strategies for QPM was solicited. One major finding was that the kernel endosperm qualities of landrace “Hickory King” need to be incorporated into new QPM varieties so as to encourage adoption. Farmers preferred getting information on QPM varieties through their local Agricultural Research and Extension (AREX) officers. A diallel study of 36 F1 QPM hybrids and their reciprocals was conducted across seven environments for agronomic traits and three environments for nutritional value traits. There were significant differences for all traits analysed using Griffing Method 3 model 1. General combing ability effects were significant and important in the control of anthesis days, kernel endosperm modification, protein content, tryptophan content, and Quality Index (QI). Specific combining ability effects were highly significant and important in the control of grain yield. There were significant SCA effects for anthesis days and QI but the proportions were lesser than the corresponding GCA effects in both traits. Kernel endosperm modification had significant GCA effects and nonsignificant SCA effects. Reciprocal-cross differences were significant for anthesis days, tryptophan content and QI. Nonmaternal effects were significant for tryptophan content whilst both maternal and nonmaternal effects were significant for QI and anthesis days. Nonmaternal effects were relatively more important than maternal effects in all the cases where there were significant reciprocal-cross differences. The cross with the highest SCA effects for grain yield was CZL03016/CML144. The most desirable cross with the lowest anthesis days was CZL03016/CML144 whilst the most desirable inbred line with the lowest anthesis GCA effects was CZL03016. The inbred line with the most desirable GCA effects for protein content, tryptophan content and QI was CML264Q. Inbred line CML264Q crossed to CZL03016 had significant SCA effects for QI. The most desirable GCA effects for kernel endosperm modification were associated with inbred line CZL03016 followed by CZL01006. Maternal effects for both tryptophan content and QI were associated with inbred line CML264Q. Genotype by environment interaction effects across all the seven environments were significant for grain yield and kernel endosperm modification. Check hybrids performed better than experimental hybrids for grain yield but were not different for kernel endosperm modification. The normal endosperm maize hybrids were significantly better for both grain yield and kernel endosperm modification. However, in all the comparisons the best check or normal endosperm maize hybrid was not significantly better than the best experimental or QPM hybrid, respectively. The most desirable score for kernel endosperm modification was from the cross of CZL01006 to CZL03016 though not significantly different from the check hybrid with the best score. AMMI1 was the best model for kernel endosperm modification scores and AMMI2 was suitable for grain yield. Both environments and hybrids were diverse. Grain yield of most hybrids was not stable with specific adaptation to environments. The most stable hybrid with no specific adaptation was CML176/CML181f with a mean yield of 6.51t ha-1. The putative nutritional superiority of normal endosperm maize pollen contaminated QPM as measured by the QI depended on the environmental conditions. The moisture stressed environment (CIMMYT Harare) had a lower QI value (0.858) and a lower tolerance to pollen contamination of 15.3% whereas the grain produced under near to optimum growing conditions (ART farm) had a higher QI value (0.915) and a higher tolerance to pollen contamination of 31.9% before total loss of nutritional superiority. Thus contaminated QPM grain had nutritional superiority up to a certain point before total loss of nutritional superiority. Geostatistical analysis was used to determine the levels and patterns of pollen contamination that occur when QPM and normal endosperm maize crops coexist under conditions minimising both temporal and geographical isolation to the lowest possible levels for the two independent crops. Higher pollen contamination levels were restricted mostly to the sections of the QPM crop proximal to the rows of normal endosperm maize crop, with the central parts of the QPM crops experiencing relatively low levels of contamination. For the four experiments (QCS200711, QCS200712, QCS200721 and QCS200722) in which the thresholds to nutritional superiority were determined, 87.9%, 94.8%, 62.2% and 65.6% of the crop areas passed for superior QPM grain, respectively. Estimates for average contamination levels of homogenous mixtures of grain from each of the nine experiments were below 20% contamination. The contamination levels were far less than previously thought. “Hickory King” kernel quality attributes were important in breeding QPM varieties for the smallholder farmers. Parents of the 72 hybrids were diverse for the agronomic characters studied and three of the experimental hybrids were found to be adapted and comparable to the check varieties. Quality protein maize tolerance to foreign pollen contamination without loss in nutritional superiority depended on growing conditions. The coexistence of QPM and normal endosperm maize without total loss of QPM nutritional superiority was feasible. / Thesis (PhD.)-University of KwaZulu-Natal, Pietermaritzburg, 2008.
20

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.

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