Towards sustainable production of sesame products: Comparison of traditional and modern production systems via a life cycle assessment approach

Abstract

Burgeoning ecological crises of food production sector has made the environmental impact evaluation of various food products a sustainability imperative. Specifically, in pursuit of identifying a sustainable production model of high-demand food items, implementing a comparative life cycle assessment of various production approaches is of paramount importance. The energy consumption and environmental impacts of manufacturing two popular sesame products, Tahini (milled sesame paste) and Halva (sweetened sesame paste) in Iran was realized by using life cycle assessment methodology. In this regard, two production systems of traditional and modern, based on sesame cultivation and processing seeds were modeled. Moreover, production of milling stone, as the main instrument in Tahini and Halva production, was evaluated within the boundary of each product system. The highest energy used pattern and carbon footprint were attributed to the traditionally produced Tahini with 89.3 MJ/kg and 12.4 kg CO₂eq/kg respectively; while, the lowest results were associated with modern-based Halva production with 47.8 MJ/kg and 5.4 kg CO₂eq/kg. Compared to the traditional method, modern production of tahini was found to increase acidification potential and ozone layer depletion potential the most, with 73.1 g SO₂eq and 0.735 mg R11eq respectively. Production of milling stone was the predominant hotspot for all products in traditional and modern systems, with average of 56% and 45% contribution to the total energy used, and 75% and 71% contribution to the carbon footprint of products in the former and latter systems respectively. Moreover, implementation of agrivoltaics system and circular economy-based milling stone as the alternative scenarios were evaluated from LCA perspective, which demonstrated that adoption of alternative milling stone could reduce the impact results significantly. It is believed that the novel evaluation framework of this study could serve as an example for future LCA studies to expand the common routine of evaluation and include production of instrument within the product's system boundary.