Environmental performance comparison of parboiled rice production

Parboiling is a process that paddy undergoes in rice production which consumes energy, water and other environmental resources. This paper presents an assessment of environmental performance of paddy parboiling methods adopted in Sri Lanka by using life cycle assessment approach. Two hot soaking methods utilising mechanical drying and sun drying and one parboiling paddy method where cold soaking is utilised are considered for comparison in this assessment. For all methods, processes from paddy harvesting to rice cooking are included in the system with a functional unit of production of one ton of parboiled rice. According to the results, the parboiling method with hot soaking and mechanical drying showed acidification and human toxicity impacts, 0.430 kg SO2 eq. and 0.552 kg 1,4-DCB eq. respectively. Cold soaking of paddy gave higher impact results in eutrophication compared to hot soaking.