In the brewing industry it is standard practice to propagate a pure yeast culture and inoculate (pitch) it into the fermentation vessel. Once fermentation is complete, yeast is recovered and reused in subsequent fermentations (known as serial repitching) until a decline in performance occurs or the required number of successive fermentations has been conducted. Propagation is currently required to initiate the entire process again, which requires additional equipment, energy, water inputs and time. It has long been proposed that Active Dried Yeast (ADY) offers an alternative method of yeast supply. Adoption of this innovation by the brewing industry has been low because of perceived issues with the fermentation performance of ADY, the availability of strains and hygiene concerns. In the current study the fermentation performance of ADY has been assessed with respect to viability, genomic stability, membrane integrity, yeast growth, attenuation, uptake of wort nutrients and aspects of flavour development. ADY requires rehydration before use and it has been demonstrated that viability is impaired in these slurries, though the extent of viability loss was dependent on strain and rehydration conditions. The source of cell death is unclear. Mitochondrial and genomic DNA integrity was assessed using a variety of techniques and shown to be unaffected by dehydration and rehydration. In contrast membrane integrity was affected. Changes in membrane fluidity, sterol content and fitness to perform could be detected in ADY. Performance of ADY in fermentation was also impaired. A lag in cell growth, attenuation and sugar and amino acid uptake were noted. Diacetyl formation occurred more rapidly and end fermentation diacetyl levels were higher for ADY. These differences were not maintained during serial repitching. It is proposed that ADY could be utilised to replace freshly propagated yeast, but direct addition to fermenters would require an improvement of performance during the first fermentation.

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Magistro baigiamajame darbe apžvelgiami ir išsamiai išanalizuojami gamybinės įmonės veiklos efektyvumo vertinimo principai, vertinimo galimybės bei metodologija. Remiantis kitų šalių patirtimi bei teorinėmis žiniomis, apsvarstytos efektyvumo gerinimo alternatyvos. Iš gautų UAB “Terekas” finansinės analizės rezultatų, atliktas pagrindinių veiklos efektyvumą įtakojančių rodiklių prognozavimas, pasitelkiant koreliacinės regresinės analizės bei eksponentinių reikšmių lyginimo skaičiavimo būdus atlikta pardavimų apimties prognozė, bendrojo bei grynojo pelno prognozės 2008-2009 metams, įvertinta įmonės bankroto tikimybė bei stabilaus augimo koeficientas. Pagal gautus rezultatus, pateiktos rekomendacijos veiklos (gamybos) efektyvumui gerinti. Patvirtinama autorės suformuluota mokslinio tyrimo hipotezė, kad gamybinės įmonės veiklos efektyvumo vertinimo rodikliai atskleidžia įmonės finansinę padėtį ir leidžia spręsti apie įmonės veiklos efektyvumą. / This Master thesis contains a review and a thorough analysis of production company’s principles of activity effectiveness evaluation, evaluation possibilities and methodology. With reference to the experience of foreign countries and theoretical knowledge, the alternatives of effectiveness improvement were discussed. The results of financial analysis were received. Thus the forecast of the main influencing indicators of the activity effectiveness was accomplished. With the help of correlation and regressive analysis as well as the calculating ways of comparing exponential values, sales volume, profit and gross profit for 2008-2009 were forecasted. The possibility of bankrupt and the coefficient of steady progress were evaluated. According to the gained results, the recommendations of improvement of activity (production) effectiveness were proposed. The scientific hypothesis of the author was proven. It claims that the evaluation indicators of a production company’s activity effectiveness reveal the financial state of a company and let decide about a company’s activity effectiveness.

Rural areas of Cameroon have limited to no availability of grid-supplied electricity, however many locations have significant hydro potential. Pico hydro (less than 5 kW generation capacity) has been identified as a promising means for rural electrification. Tests of previously implemented designs and field research in Cameroon were conducted to contextualize the design process. Field research involved end-user and artisan interviews, market research, site investigations, and artisan collaboration. Findings were used to select an axial flow propeller for the improved turbine. Detailed design used turbomachinery theory towards the development of a locally manufactured low head pico hydro turbine for rural electrification. A propeller turbine with complex blade geometries was designed but simplified to incorporate flat blade geometries to better suit the local manufacture capabilities. A prototype turbine was built and tested. The flat blade propeller turbine performed reasonably well, but was unable to achieve desired power generation targets with predefined head and flow rate conditions.

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This dissertation is concerned with the application of tomography within the sugar industry; in particular non-accessible locations found in a sugar mill. In this study, the focus of research is that of a vacuum pan, and if better understood through tomographical techniques could significantly improve mill efficiency and throughput. The tomography system comprises unique mechanical interfaces, data acquisition modules and software algorithms in order to generate images which reflect the dynamics in the tomographical sensor zone. The distribution of gas (low conductivity) and liquid (high conductivity) within a tube is of main interest in order to understand the boiling dynamics and ultimately pan design. This is attained by determining the internal cross-sectional spatial distribution of conductivity of a number of tubes within the pan simultaneously. Thermal properties of the contents of the sugar pan (a syrup-like substance known as massecuite) at different boiling stages can be estimated based on the tomographical data. Data acquisition is achieved via an in-house designed electronic state machine. A neighbourhood back-projection reconstruction technique was developed in MATLAB in order to generate tomographical images. Results from the system have identified different boiling dynamics which improve the understanding and design of vacuum sugar pans. / Thesis (M.Sc.Eng)-University of KwaZulu-Natal, Durban, 2010.

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To reduce the amount of sodium chloride in breakfast cereals without changing their properties, it is necessary to understand the role of this salt. Hence, a model system was developed. This model, composed of native waxy maize starch, glucose and a mixture of amino-acids generated similar colour and residual volatiles after heating compared to commercial breakfast cereals. Systematically designed experiments used this model to study the influence of NaCl concentration (0 % to 5.44 %) on colour, residual volatiles and acrylamide formation. It was found that higher NaCl concentration led to darker products (p<0.05) and significantly decreased acrylamide formation in the model systems. However, it did not have a significant impact on residual volatile levels. These findings were confirmed by observations made on wheat, wheat and rice mixture, com and rice commercial cereals. The impact of NaCl on colour and acrylamide formation indicated that this salt might influence Maillard and/or caramelisation rates and pathways. As NaCl is a plasticiser, it can allow the rubbery state to be maintained for a longer period during heating, improving reactants' mobility and Maillard reactions. However, it was found using the model systems mixed with several types of plasticisers (NaCl, KCl or trehalose), that the NaCl plasticising effect was not the major influence. The models also demonstrated that the hygroscopic behaviour of NaCl was not linked to its impact on colour and acrylamide formation. In investigating salt's influence on starch, native waxy maize, cassava or potato starch were mixed with NaCl (0 to 4 %; moisture adjusted to 20 %) and were heated at 230°C for 45 min. Microscopic observations, wide angle X-ray, viscosity, intrinsic viscosity and DSC data all suggested that starch was degraded by the heat treatment, and NaCl accelerated starch break down into smaller molecules, i.e. glucose. The glucose potentially formed could then caramelise, which might explain the NaCl impact on colour formation in model systems and breakfast cereals. Among other tested salts, CaCl[subscript]2 and MgC1[subscript]2 also enhanced starch degradation during a heat treatment. In studying glucose solutions containing salt (NaCl, CaCl[subscript]2 or MgCl[subscript]2) and heated between 180 and 230 °C, it was observed that salt enhanced colour formation via caramelisation (p<0.05). Mixtures of glucose, amino-acids and salt (NaCl, CaCl[susbscript] or MgCl[subscript]2), heated under the same conditions, showed that salt significantly decreased colour formation (p<0.05), which was most likely generated via Maillard reactions. Hence, salts could slow down Maillard reactions, explaining why lower acrylamide contents were found in model systems and cereal products when NaCl was present. As NaCl seems to influence Maillard and caramelisation reactions, decreasing or removing NaCl from breakfast cereal recipes might not only alter the salty taste but also the overall flavour. CaCl[subscript]2 and MgCl[subscript]2 seemed to have similar or even more impact on colour formation compared to NaCl. Adding these salts to breakfast cereal products with a low NaCl content was found to compensate for the colour loss. Adding CaCl[subscript]2 or MgCl[subscript]2 also improved the overall flavour of breakfast cereals, even though it did not compensate entirely for the taste loss.

Outsourcing of pharmaceutical manufacturing processes from developed countries to emerging economies such as India and China, has become increasingly frequent during the last decade. Simultaneously, impacts and risks associated with pharmaceuticals in the environment, particularly from manufacturing of Active Pharmaceutical Ingredients (APIs), have gained recognition as major threats to sustainable development, locally (due to pollution of ground- and surface water) as well as globally (due to risks with antibiotic resistance development). The purpose with this study is to examine the pollution situation in two main locations for API manufacturing in Andhra Pradesh, and its challenges, as well as the eventual possibilities and barriers to improve the situation. Based on semi-structured interviews with local stakeholders from industry, government and NGOs, site observations and community visits in affected areas, as well as a literature review, a critical examination of the situation and its potential sustainability measures was made. Furthermore, the connection to- and role of Swedish actors were explored. The study finds that there are major institutional challenges rather than technological ones, obstructing substantial improvements from taking place. Potential possibilities for pollution abatement include local initiatives e.g. alternative regulatory approaches as well as initiatives by international actors, such as large procurers of pharmaceuticals e.g. the Swedish county councils, which with policy instruments such as Green Public Procurement (GPP), pro-active and internationally coordinated efforts, could contribute to an improved situation.

The differences between conventionally processed and extruded puffed rice were examined, with a view to determining the reasons for their different storage behaviour in confectionery. Differences between the two forms of puffed rice have been identified, both in their performance and their properties. Under certain viewing conditions, the starch granules in conventionally processed and extruded rice appear to be different. The starch granules in conventionally puffed Rice remain intact, but with no crystalline structure (i.e. no Maltese crosses are visible, though starch ghosts are abundant.) Cell walls of conventionally processed rice appear to be a layer of these gelatinised intact granules. The ghostlike granules have not undergone notable swelling, remaining slightly greater than 10μm in diameter, similar to the size of unprocessed granules. In contrast, the starch granules in extruded puffed rice are rarely visible, in either their birefringent Maltese cross form, or as gelatinised but intact ghosts. By altering the extrusion conditions, the microscopic appearance of the product and its behaviour in water or water vapour becomes similar to that of conventionally processed rice. The extrusion parameters required for this similarity to conventionally processed rice fall within a window that is relatively narrow when compared to the ranges of variables available. Under more severe processing conditions the granules lose their integrity because shear and heat disrupt them. Under less severe conditions, the granules form clusters that do not gelatinise. The conditions at which this product is made cannot be interpolated or extrapolated from samples made under other conditions. However, at these extrusion parameters, the extrudate does not expand. It is necessary to expand the extrudate separately from the extrusion process. A novel method for the analysis of multi-peak force responses from compression of low moisture puffed cereal products was developed. This enabled crisp and crackly to be distinguished instrumentally. The results correlated well with sensory evaluation.