title: Effects of Drying Conditions on Protein Properties of Blood meal

authors: Damba, Chawangwa

subjects: Effects of Drying Conditions on Protein

abstract: Blood meal is a by-product of the meat industry produced through drying of animal blood. It contains about 85 wt.% proteins. Drying has been used as a method to preserve biomaterials and involves lowering of the water activity of biomaterials. The purpose of this research was to study the drying kinetics of producing blood meal in an oven dryer, to evaluate suitable drying models for describing the drying process and to determine the effects of drying conditions on the physio-chemical properties of blood meal.
Moisture content and drying rates were determined by drying coagulated blood at different temperatures (60 °C, 100 °C and 140 °C) for a constant period of 24 hours. The initial moisture content of coagulated blood was about 60.7 wt% on a wet basis. A drying temperature of 140 °C was found to be the optimal for routine moisture determination for coagulated blood as equilibrium moisture was achieved within 24 hours period. A constant drying rate period was not observed in any of the conditions tested, and the initial increasing rate period as followed by a short transition phase prior to the falling-rate period. Thus, moisture removal from the coagulated blood was governed by a diffusion-controlled process.
The experimental drying data for coagulated blood was used to fit the Lewis, Page, Modified Page, Logarithmic and Henderson and Pabis models and the statistical validity of models tested were determined by non-linear regression analysis. The Page model had the highest R² (0.9999) and lowest χ² (0.0001) and RMSE values. This indicated that Page model adequately described the oven drying behaviour of coagulated blood. 
Blood meal samples were produced by drying coagulated blood at different temperatures (60 °C, 100 °C, 140 °C) to varying moisture contents (5 %, 10 % and 15 %). A drop penetration test using water and/or sodium dodecyl sulphate dissolved in water were used to determine the wettability of the samples produce while thermal analysis techniques such as Thermo-Gravimetric Analysis (TGA), Differential Scanning Calorimetry (DSC) and Dynamic Mechanical Analysis (DMA) were used to investigate the thermal properties of bloodmeal. X-ray scattering was used to investigate conformational changes in blood meal proteins during drying. 
Drying conditions had substantial effects on both physicochemical and thermal properties of blood meal. It was established that drying temperature had a more significant effect on the wettability of blood meal than the final moisture content. However, the final moisture content had larger contribution to the thermal stability of blood meal than drying temperature. Blood meal produced at 60 °C to 15% moisture content was the most stable sample while blood meal produced at 140 °C to 10% moisture content was the least stable.
Protein denaturation was observed at 92 °C to 122 °C, depending on moisture content and drying temperature. DMA results revealed that different relaxations occurred when drying coagulated blood. A dry glass transition temperature for samples was observed between 219 °C - 226.8 °C. This suggested that bound water does not act as plasticiser in blood meal. Glass transitions observed in DSC were therefore, considered more accurate and reliable for blood meal samples containing moisture. Drying of coagulated blood was observed to have drastic effect on the structural arrangement of coagulated blood in XRD. Increase in moisture content was observed to have an effect on the β-sheets structure of samples dried at 60 °C and 100 °C. Since bloodmeal produced at 60 °C and 100 °C did not show complete denaturation of proteins, future thermoplastic processing should consider blood meal produced within this temperature range for improved properties.

text: Effects of Drying Conditions on Protein Properties of Blood meal Blood meal is a by-product of the meat industry produced through drying of animal blood. It contains about 85 wt.% proteins. Drying has been used as a method to preserve biomaterials and involves lowering of the water activity of biomaterials. The purpose of this research was to study the drying kinetics of producing blood meal in an oven dryer, to evaluate suitable drying models for describing the drying process and to determine the effects of drying conditions on the physio-chemical properties of blood meal.
Moisture content and drying rates were determined by drying coagulated blood at different temperatures (60 °C, 100 °C and 140 °C) for a constant period of 24 hours. The initial moisture content of coagulated blood was about 60.7 wt% on a wet basis. A drying temperature of 140 °C was found to be the optimal for routine moisture determination for coagulated blood as equilibrium moisture was achieved within 24 hours period. A constant drying rate period was not observed in any of the conditions tested, and the initial increasing rate period as followed by a short transition phase prior to the falling-rate period. Thus, moisture removal from the coagulated blood was governed by a diffusion-controlled process.
The experimental drying data for coagulated blood was used to fit the Lewis, Page, Modified Page, Logarithmic and Henderson and Pabis models and the statistical validity of models tested were determined by non-linear regression analysis. The Page model had the highest R² (0.9999) and lowest χ² (0.0001) and RMSE values. This indicated that Page model adequately described the oven drying behaviour of coagulated blood. 
Blood meal samples were produced by drying coagulated blood at different temperatures (60 °C, 100 °C, 140 °C) to varying moisture contents (5 %, 10 % and 15 %). A drop penetration test using water and/or sodium dodecyl sulphate dissolved in water were used to determine the wettability of the samples produce while thermal analysis techniques such as Thermo-Gravimetric Analysis (TGA), Differential Scanning Calorimetry (DSC) and Dynamic Mechanical Analysis (DMA) were used to investigate the thermal properties of bloodmeal. X-ray scattering was used to investigate conformational changes in blood meal proteins during drying. 
Drying conditions had substantial effects on both physicochemical and thermal properties of blood meal. It was established that drying temperature had a more significant effect on the wettability of blood meal than the final moisture content. However, the final moisture content had larger contribution to the thermal stability of blood meal than drying temperature. Blood meal produced at 60 °C to 15% moisture content was the most stable sample while blood meal produced at 140 °C to 10% moisture content was the least stable.
Protein denaturation was observed at 92 °C to 122 °C, depending on moisture content and drying temperature. DMA results revealed that different relaxations occurred when drying coagulated blood. A dry glass transition temperature for samples was observed between 219 °C - 226.8 °C. This suggested that bound water does not act as plasticiser in blood meal. Glass transitions observed in DSC were therefore, considered more accurate and reliable for blood meal samples containing moisture. Drying of coagulated blood was observed to have drastic effect on the structural arrangement of coagulated blood in XRD. Increase in moisture content was observed to have an effect on the β-sheets structure of samples dried at 60 °C and 100 °C. Since bloodmeal produced at 60 °C and 100 °C did not show complete denaturation of proteins, future thermoplastic processing should consider blood meal produced within this temperature range for improved properties.

year: 2017

title: Experimental performance of water cooled building integrated photovoltaic/thermal solar collectors

authors: Anderson, Timothy Nicholas

subjects: BIPVT

abstract: The idea of integrating water cooled photovoltaic/thermal collectors into building structures (BIPVT collectors) to provide electrical and heat energy is an area that has received only limited attention. BIPVT collectors are particularly attractive, as the integration of a single photovoltaic and thermal collector into the long-run roofing structure of a building could provide greater opportunity for the use of renewable solar energy technologies. In this study, the thermal efficiency of a novel low cost water cooled building integrated photovoltaic/thermal (BIPVT) solar collector was experimentally measured. The results show that despite being made of a typical roofing material, the thermal efficiency is not unreasonably affected. Furthermore, it is shown that the measured efficiency is similar to that predicted by the Hottel-Whillier equations.

text: Experimental performance of water cooled building integrated photovoltaic/thermal solar collectors The idea of integrating water cooled photovoltaic/thermal collectors into building structures (BIPVT collectors) to provide electrical and heat energy is an area that has received only limited attention. BIPVT collectors are particularly attractive, as the integration of a single photovoltaic and thermal collector into the long-run roofing structure of a building could provide greater opportunity for the use of renewable solar energy technologies. In this study, the thermal efficiency of a novel low cost water cooled building integrated photovoltaic/thermal (BIPVT) solar collector was experimentally measured. The results show that despite being made of a typical roofing material, the thermal efficiency is not unreasonably affected. Furthermore, it is shown that the measured efficiency is similar to that predicted by the Hottel-Whillier equations.

year: 2008

title: Restoring the flow: Challenging the existing management frameworks to integrate Mātauranga Māori

authors: Hall, Tredegar Rangiātea

subjects: tangata whenua water management

abstract: Within the context of the current regimes of fresh water management in Aotearoa, this thesis is an exploration of the significance of freshwater to Māori; our rangatiratanga, Treaty rights and ownership. The Māori world view and the way this relates to fresh water is described and contrasted with the principles and practices of water management in the contemporary neo-liberal governance structures of this country. The impacts of the commodification of water through ownership rights, the limited monitoring capacity and the inability to provide a governance structure that will work across diverse environments are seen to threaten the sustainability of a critical part of our environment. The primary focus of on this research is on the relationship between the exclusion of tangata whenua from decision making in resource management and the degradation of the environment.
 
The thesis comments on the development of resource management legislation and actions of the state in Aotearoa, and uses post-colonial theory as a starting point to document the subordinate relationship of Māori within contemporary governance. This has privileged mono-cultural and neoliberal forms of water management that has scarred Papatūānuku and threatens human sustainability into the future.
    
The recent co-management agreement for the Waikato River is the specific case study against which a recent effort to reduce the alienation of Māori is viewed. A kaupapa Māori methodology is used to acquire and understand the importance of mātauranga Māori/ Traditional Ecological Knowledge (TEK) and what is required for these principles to enhance water management practices within the case study area. The original contribution of the work is drawn from interviews conducted with Māori and others who are involved in or informed by the commitment to explore co-management sustainable management options. These views are woven into a substantial and interpretative commentary on the role of Māori in future water governance.

The thesis argues that the best way to enhance water management and environmental protection is by inducing a planning paradigm shift where tangata whenua are given greater influence in environmental decision making that resembles an equal Treaty of Waitangi partnership, where the ethic of kaitiakitanga is empowered. Such a strategy would allow decision making regarding water and environmental management to be more focused on what is best for the resource and its survival rather than what most cost effective for some owners of water rights. Encouraging the acceptance of mātauranga Māori and incorporating more efficient and sustainable innovative technologies can restore the mauri of water in our place.

text: Restoring the flow: Challenging the existing management frameworks to integrate Mātauranga Māori Within the context of the current regimes of fresh water management in Aotearoa, this thesis is an exploration of the significance of freshwater to Māori; our rangatiratanga, Treaty rights and ownership. The Māori world view and the way this relates to fresh water is described and contrasted with the principles and practices of water management in the contemporary neo-liberal governance structures of this country. The impacts of the commodification of water through ownership rights, the limited monitoring capacity and the inability to provide a governance structure that will work across diverse environments are seen to threaten the sustainability of a critical part of our environment. The primary focus of on this research is on the relationship between the exclusion of tangata whenua from decision making in resource management and the degradation of the environment.
 
The thesis comments on the development of resource management legislation and actions of the state in Aotearoa, and uses post-colonial theory as a starting point to document the subordinate relationship of Māori within contemporary governance. This has privileged mono-cultural and neoliberal forms of water management that has scarred Papatūānuku and threatens human sustainability into the future.
    
The recent co-management agreement for the Waikato River is the specific case study against which a recent effort to reduce the alienation of Māori is viewed. A kaupapa Māori methodology is used to acquire and understand the importance of mātauranga Māori/ Traditional Ecological Knowledge (TEK) and what is required for these principles to enhance water management practices within the case study area. The original contribution of the work is drawn from interviews conducted with Māori and others who are involved in or informed by the commitment to explore co-management sustainable management options. These views are woven into a substantial and interpretative commentary on the role of Māori in future water governance.

The thesis argues that the best way to enhance water management and environmental protection is by inducing a planning paradigm shift where tangata whenua are given greater influence in environmental decision making that resembles an equal Treaty of Waitangi partnership, where the ethic of kaitiakitanga is empowered. Such a strategy would allow decision making regarding water and environmental management to be more focused on what is best for the resource and its survival rather than what most cost effective for some owners of water rights. Encouraging the acceptance of mātauranga Māori and incorporating more efficient and sustainable innovative technologies can restore the mauri of water in our place.

year: 2012