Environmental performance of new processes for the production of fructo- and galacto-oligosaccharides (FOS and GOS)

Abstract

International audienceThe prebiotics like FOS and GOS are receiving special attention in the food industry due to their health benefits.They can be produced by enzymatic synthesis by using disaccharides or other substrates as raw materials orby extraction and hydrolysis from different natural sources (roots, legumes). The environmental footprints ofthese different production schemes are lacking to provide guidance for the ecodesign of such new productionprocesses.In this work, Life Cycle Assessment (LCA) was undertaken to analyze and compare the production of FOSand GOS by enzymatic synthesis from glucose (to get FOS) or lactose (to get GOS) and hydrolytic productionfrom extraction of yacon potato (to get FOS) or chickpea (to get GOS).A cradle-to-gate approach was considered in the two scenarios under assessment (the phases of use and/or finaldisposal of FOS/GOS were not considered). The functional unit was defined as 100 g of FOS/GOS produced.LCAs were performed using data collected at the laboratory scale, supplemented with data from Ecoinventdatabase. SimaPro was used for the LCA modeling with the midpoint impact EF2.0 characterization method.Results showed that the main environmental hotspot was the production of yacon potato or chickpea used inthe hydrolysis process. For this reason, the hydrolytic process caused higher environmental burdens than theenzymatic synthesis process. Chickpea production causing more impacts than yacon potato production, GOSproduction generated more environmental impacts than FOS production. When produced by enzymaticsynthesis, FOS and GOS were the sources of similar environmental impacts.From a process point of view, special attention must be paid on three specific stages of production: time ofsynthesis, freeze-drying and purification of the final product. The environmental load of these stages wasassociated to high energy consumption and huge amount of ethanol requirement.The results from this study helped to identify the stages requiring special efforts to ecodesign the productionof FOS and GOS at pilot scale in the future. Further research should primarily be focused in the reduction ofthe biomass used and corresponding solid waste generated during the hydrolytic production. Furthermore,environmental assessment should be included at each development of the process to ensure its efficient ecodesign