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MA RESEARCH REPORT Prepared for the Department of Development Studies, University of the Witwatersrand, Johannesburg June 2016 / This research argues that food sovereignty offers a plausible alternative to the current unjust, unsafe and unsustainable food system in South Africa. In addition, it argues that food sovereignty provides important solutions to hunger and the brutalities of the food system which current policies and interventions fail to address. Food sovereignty is an ideal that originated amongst a peasant movement in the global South. This ideal and framework to address hunger has since evolved and spread to international movements, and is making great strides in advocating for change in the current broken food system. Food sovereignty has lately been adapted in South Africa as a grassroots led initiative promoted by the nascent South African Food Sovereignty Campaign (SAFSC). This research uses the SAFSC as a case study to explore food sovereignty alternatives in South Africa. It does this by using in-depth interviews and participant observation in the campaign to draw out understandings of food sovereignty particular to South African activists. It further assesses tactics and strategies the SAFSC uses, and compares these to current state, business and civil society organisations’ solutions to show how a more grassroots-led approach, using the food sovereignty framework, has the potential to address the roots of hunger. These roots of hunger are shown to be at the corporate food regime level, as has been indicated by the literature and confirmed in this research. As food sovereignty is pursued by various actors in South Africa it provides important examples of approaches by which power in the food system can be reclaimed to benefit the majority instead of a few elites, as is currently the case.

This item was digitized as part of the Million Books Project led by Carnegie Mellon University and supported by grants from the National Science Foundation (NSF). Cornell University coordinated the participation of land-grant and agricultural libraries in providing historical agricultural information for the digitization project; the University of Arizona Libraries, the College of Agriculture and Life Sciences, and the Office of Arid Lands Studies collaborated in the selection and provision of material for the digitization project.

The performance of a new horizontal retort (Steriflow Standard 1-Basket Model, Barriquand, Paris, France) was evaluated on the basis of temperature, heat and lethality distribution. Time-temperature data for these studies were obtained from bare thermocouples (type T), and rectangular bricks fabricated from Teflon$ sp{ rm TM}$ and Lexan$ sp{ rm TM}$ with thermocouples positioned at their geometrical centres. / The effect of entrapped air on processing parameters for bricks packaged in retort pouches was determined using silicone rubber bricks (10 x 14.5 x 2 cm), containing 5 thermocouples with their junctions positioned from the geometrical centre to near the top surface. The processing media employed were steam/air at two temperatures (121.1$ sp circ$C and 115.6$ sp circ$C) and two levels of superimposed air over-pressure, corresponding to 65% and 75% steam content. / With the exception of the highest level of over-pressure (116 kPa), 60 ml of entrapped air caused the heating rate index (f$ sb{ rm h}$) to double. At low levels of air over-pressures, the slowest heating region (often assumed to be the geometrical centre) in the brick was shifted to a height equivalent to 3/4 of the brick thickness from the centre when the entrapped air volume was 60 ml. For similar conditions, the location receiving the least combined lethality during heating and cooling was near the top surface of the brick.

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The convective fluid-to-particle heat transfer coefficient (hfp ) is one of the critical factors influencing the process design for multi phase food products, in continuous tubeflow systems. Determination of hfp associated with moving particles poses a unique challenge to investigators because of the difficulty in monitoring the temperature of moving particles without interfering with the particle motion. Two different techniques involving particle motion were developed to evaluate hfp and to study the effects of factors influencing hfp, associated with spherical particles under tube-flow conditions. / Spherical Nylon particles with centrally located fine-wire flexible thermocouples, were suspended from the upper mid-section of a curved glass tube in order to provide lateral movement of the particle as the tube was subjected to oscillatory motion. / A full factorial experimental design was studied involving spherical particles made of Aluminum epoxy and Nylon of different diameters (12.7 to 17.5 mm), particle linear velocities (0.06 to 0.21 m/s), heating medium viscosities (0 to 1% Carboxymethyl cellulose, CMC) and fluid temperatures (60 to 80°C). The above factors had a significant (p < 0.001) effect on hfp. Depending on experimental conditions the values of h fp varied from 350 to 2000 W/m2K. Overall, hfp values associated with the aluminum epoxy particle were about 30% higher than that for the Nylon particle. / A calorimetric method was developed to evaluate hfp associated with a freely moving particle. / The calorimetric method was used to evaluate the effect of fluid flow rate, viscosity and temperature, as well as particle size on the associated hfp under tube-flow conditions. Experiments were carried out using different flow rates (9 to 19 L/min), fluid viscosity (0 to 1% CMC solution) and fluid temperature (50 to 70°C) as well as Aluminum spherical particles of different sizes (19 to 25.4 mm). Values of hfp varied from 650 to 2660 W/m2K, and increased significantly (p < 0.001) with an increase in fluid flow rate and particle size, whereas a decrease was observed with CMC concentration and temperature. / Several correlations were developed in the form of Nusselt number as a function of other influencing dimensionless numbers. Nusselt numbers estimated from the developed equations showed good agreement with the experimental data (0.88 < R2 < 0.99). (Abstract shortened by UMI.)

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Food loss and waste represent a significant challenge to global sustainability. In a world where the number of people suffering from hunger has been rising, approximately 1.3 million tonnes of food are lost or wasted each year. When food is lost or wasted, all the resources used to produce it, including water, land, energy, labor, and capital, are also lost. In addition, it is estimated that the disposal of food in landfills generates 11% of all greenhouse gas emissions, thereby contributing to climate change. Food loss and waste can also have a negative impact on food security and prices. This dissertation introduces non-invasive and chemicals-free solutions for the shelf-life extension and quality monitoring of fresh foods. First, we propose the creation of a sterilized anaerobic storage environment using UV-C irradiation and vacuum sealing for increasing the shelf-life of perishables. The proposed combination was tested on fresh strawberries and quartered tomatoes and has successfully increased the shelf-life by 124.41% and 54.41%, respectively, while acceptable sensory characteristics were maintained throughout the storage period. Second, the proposed combination was tested on fresh beef, chicken and salmon fillets, where a shelf-life increase of 66% was achieved. The shelf-life of strawberries, tomatoes and meats were determined by monitoring the organoleptic qualities and counting the microbial populations of various bacteria, which includes aerobic bacteria, Lactic Acid Bacteria, Pseudomonas spp., yeast, mold, Salmonella and E-coli in addition to pH measurements. In the third part, we propose an IoT-enabled electronic nose system for rapid beef quality monitoring. The e-nose system includes carbon dioxide, ammonia, and ethylene sensors to measure the volatile organic compounds' (VOCs) concentrations. Microbial population quantifications of various bacteria were conducted to identify the concentrations of VOCs that are associated with raw beef spoilage. The production of VOCs was correlated with the proliferation of bacteria using linear regression, and it was discovered that aerobic bacteria and Pseudomonas spp. play a significant role in the production of VOCs in raw beef, as opposed to LAB. This system demonstrates how the IoT-enabled e-nose system can be an effective tool for monitoring the quality of perishables.

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