Techno-economic analysis for production of red beet food colourant

• Techno-economic analysis of three process pathways to produce red beet food colourant. • Aqueous two-phase extraction-based purification is employed to increase the product purity. • Anaerobic digestion of beet pulp waste is explored for sustainable energy integration. • The sensitivities of process conditions and economic parameters on MSP are analysed. Natural food colourants have gained significant importance in the food processing industry due to their health benefits, consumer preferences, and regulatory compliance. Beyond colouring, some, like curcumin and betanin, also enhance flavour and act as natural preservatives. In this paper, a comprehensive techno-economic analysis (TEA) for betanin production and purification is presented, with the aim of modelling existing pathways and assessing the economic trade-off between purity requirements and production costs. The current research focuses on three different encapsulation and purification pathways for the production of betanin: spray-drying (BC-SD), freeze-drying (BC-FD), and aqueous two-phase extraction with spray-drying (BC-ATPE-SD), and for each case, the minimum selling price (MSP-$/kg) is calculated. The feasibility of utilizing beet pulp waste through anaerobic digestion to facilitate in-house energy generation is explored to enhance the sustainability of the process. The proposed pathways are simulated using SuperPro Designer , and a systematic economic analysis is carried out targeting 10% of the forecasted betanin market volume. The MSP for betanin is calculated as $7.39/kg and $110.95/kg for BC-SD and BC-FD, respectively. However, betanin produced by these production pathways still offers low purity (⁓0.54% betanin) due to the presence of significant amounts of sugars. Aqueous two-phase extraction (ATPE)-assisted purification is proposed to reduce sugars in the final product, which differentially partitions betanin and sugar. This method is combined with cost-effective spray drying to produce betanin. TEA showed a ⁓350% increase in the product purity (as % betanin) with a projected MSP of $43.49/kg. The influence of the ATPE compositions on product purity and process economics is comprehensively studied. A single-point sensitivity analysis is also carried out to study the influence of process conditions, raw material costs, and economic parameters on the product MSP ($/kg).