Assessment of processing of some fruit and vegetable products using exergy and life cycle analyses

Food processing is a highly energy-consuming procedure that frequently has environmental effects that cannot properly identified or measured. The food business, particularly food processing, is widely recognized for its significant dependency on resources and energy, resulting in notable environmental consequences. On the other hand, food is an essential necessity for humans, and the adoption of sustainable practices in food production has gained significant importance in contemporary times. Identifying and quantifying the inefficiencies in food production processes and proposing improvements that can lead to more sustainable production practices by combining exergy analysis with life cycle analysis (LCA), which can provide a more detailed understanding of the environmental impacts and energy efficiency of food processing operations is a relatively new, effective and feasible approach. This thesis presents a comprehensive assessment of the production processes of selected products in the fruit and vegetable processing sector using cumulative energy, exergy, carbon dioxide (CO₂) emissions, and LCA with a farm to fork and cradle to gate approach. In order to achieve these goals, a thorough analysis of the different stages of production, such as the farming, processing, and packaging and transportation processes, is carried out. Energy, exergy, CO₂ emissions, and LCA metrics have been calculated as a base case, for each stage of production in order to identify hotspots for energy, exergy consumption, and environmental impact. The two most widely consumed raw materials, tomato and sweet red pepper (SRP), were selected as representatives of the global fruit and vegetable sector. The study examined the processed tomato products, including retail tomatoes, tomato juice, tomato paste, and sweet red pepper products such as retail SRP, SRP paste, roasted SRP, and dried SRP. Of all the calculated parameters, the farming and packaging-transportation steps emerged as the primary contributors among the production steps. Diesel consumption, electricity, natural gas, fertilizer use, steel, and glass packaging as inputs; evaporation, sterilization, and aseptic filling as equipment have been determined to be the major contributors of all evaluated metrics among all components examined in the study. Abiotic (fossil) depletion (AFDP), global warming potential, fresh water aquatic ecotoxicity, and human toxicity potentials were determined to have the highest environmental implications among the life cycle impact categories. It is observed that the base case exhibits the highest values for cumulative energy consumption (CEnC), cumulative exergy consumption (CExC), and cumulative carbon dioxide emission (CCO₂C) and LCA. Conversely, the biodiesel scenario (BD) demonstrates the lowest values, followed by the precision farming scenario (PF). The application of BD has resulted in a decrease in the cumulative energy value from 3320.12 MJ/ton to 1380.40 MJ/ton in retail tomato production. Considering the application of PF in tomato farming, there is a reduction of 14.7% in the CEnC value. Global warming potential required to produce one metric ton of fresh tomato in study is 120 kg CO₂-eq. On the orher hand, the primary factor contributing to all evaluated metrics of retail SRP is the utilization of fertilizers possessing CEnC, CExC, and CCO₂C values of 87%, 71%, and 32% respectively. One ton of fresh SRP results in the emission of 39.82 kg/ton of CO₂, with CEnC and CExC values of 2742.20 MJ/ton and 1387.91 MJ/ton, respectively. It is recommended to increase the use of biodiesel in factory processing and transportation. Increasing consumer awareness of the adverse impacts that various farming methods and packaging materials have on the environment can stimulate the market for sustainably produced goods. The implications of these findings are significant for industry stakeholders who want to improve energy efficiency and lessen their environmental impact. By illustrating how energy and life cycle analyses can be used practically to identify and mitigate inefficiencies in food production processes, this study promote the field of sustainable food production. Subsequent investigations ought to concentrate on the execution of the suggested enhancements and their enduring consequences on production effectiveness and ecological implications. To further improve process sustainability, future studies should apply these techniques to a wider range of products and investigate cutting-edge technologies.