Analysis and modeling of agricultural processing with regard to grain post-harvest handling and winemaking

With increasing human population, urbanization and modernization, the shortage of food and energy as well as environmental impacts have become serious problems threatening the existence of humankind. The optimization of agricultural processing could be a valid way to relieve these problems by producing more high-quality agricultural products with fewer resources and less impacts on the environment. Agricultural processing has been defined as an activity which is performed to maintain or improve the quality of an agricultural product or to change its form or characteristics. This includes drying, storage, milling, packaging, brewage, etc. A critical step to optimize agricultural processing is to characterize, understand and predict it by analysis and modeling. The purpose of this research is to discuss it by conducting analysis, assessment and modeling for a complex grain farm including a vineyard with grain and red wine as product. Specific applications including analysis and modeling of grain hermetic storage reduce the impacts of pest infestation, analysis and assessment of the efficiency of a closed circuit grain drying system, and systemic economic analysis plus life-cycle assessment with respect to winemaking were discussed. In the first study, a time-dependent model was developed to determine the effect of hermetic storage conditions on red flour beetle (Tribolium castaneum) and maize weevil (Sitophilus zeamais). The counts of live and dead insects were examined over time in storage of wheat and maize, using both hermetic and non-hermetic conditions. It was found that 100% mortality for red flour beetle was obtained after 12 days for wheat under hermetic conditions. It was also found 100% mortality of maize weevils after 6 days of hermetic storage of corn. The results have demonstrated that hermetic treatment is a valid and efficient way to kill red flour beetle (Tribolium castaneum) and maize weevil (Sitophilus zeamais). Data collected and model developed could be further used for scale up design of full-scale storage systems for grain. The efficiency of a closed circuit grain drying system named the DOROTHY cyclone moisture removal system was analyzed and assessed in the second study. The system was designed and manufactured by the Loebach brothers (David R. Loebach and Joseph E. Loebach, Loebach Brothers Inc., sailboatcw@gmail.co), and consisted of a wagon to hold the grain and a drying apparatus composed of a compressor, an evaporation-condensation-system and a fan. Two trials were operated separately in fall and winter, using corn to evaluate drying efficiency. Power and moisture content were analyzed during experiment. Energy consumption and moisture removal could be utilized to calculate drying efficiency. The effect on germination was also evaluated after the drying process. Results showed that the drying system in the fall trial was very efficient compared to common drying systems on the market and did not decrease germination. While in the winter trial, the efficiency of the drying system decreased by half compared to the fall trial but was still comparable to the common drying systems used in industry. Additionally, germination performance was not affected. In the last study, TEA (Techno-economic analysis) and LCA (Life cycle assessment) for the production of red wine was conducted for providing information with regard to economy and environment to help to make decision when establishing a winery. For LCA, the consumption of water, energy, greenhouse gas emissions, and solid waste generation were considered for environmental impacts. For TEA, small, medium and large-scale winemaking processes were chosen for analysis and a spreadsheet-based economic model was developed. The results of the LCA showed that bottle manufacturing, vine planting and winemaking processes contributed the greatest environmental impacts. While for the TEA, the relationship between cost and profit among all three scales fitted an exponential model, and fitted a liner model better. Overall, this thesis has shown several specific applications of analyzing, assessing and modeling of agricultural processing to indicate, predict and optimize it. The author believes such applications could be conducted not only for the specific practices mentioned in this thesis, but also could be conducted for all kinds of agricultural processing, therefore reducing the problems associated with food, energy and impacts on environment caused by the increase of human population