Design of a sustainable biorefinery for the valorization of waste from the baker's yeast industry through process simulation: A case study for the production of animal feed, fertilizers, and biofuels from vinasse.

The present work deals with the biotechnological valorization of the vinasse through a sustainable biorefinery. The aim was to design and analyze, through process simulation, a biorefinery for the valorization of vinasse in products such as organo-mineral fertilizers, supplements for animal feed, and biogas. For this purpose, the SuperPro Designer software was used, and a modified hierarchical decomposition method was applied. One base case and three scenarios were techno-economically assessed, and the net present value was used as a selection criterion. The technological configuration with the best techno-economic criterion was analyzed socially and environmentally. The results suggest that the best configuration of the biorefinery corresponded to scenario 3, with a net present value of USD$73,364,000, a number of direct employees of 38, and a blue water footprint of 16.16 m3/h. These findings highlight the potential of the design of biorefineries to address the valorization of vinasses in Colombia and worldwide.

Valorisation of rejected unripe plantain fruits of Musa AAB Simmonds: from nutritional characterisation to the conceptual process design for prebiotic production.

The increasing consumption of plantain fruits with specific quality standards generates high agricultural waste. This work aimed at valorising the rejected unripe pulp of Dominico-Hartón plantain fruits (Musa AAB Simmonds). The pulp was characterised physico-chemically, thermally and functionally. The data gathered experimentally and collected from different databases were used to design a production process of isomalto-oligosaccharides (IMO) syrup. The plantain flour contains high levels of starch (87 ± 2%) and amylose (31.2 ± 0.8%). The flour showed stability at high temperatures (pasting temperature of 79.26 ± 0.02 °C), allowing its use in high temperature processes. In vitro gastrointestinal digestion of the plantain flour showed that when cooked, the glycemic index of the flour increased from 47.7 ± 2.2 to 84.2 ± 1.8, while its resistant starch content only slightly decreased from 71.7 ± 1% to 52.6 ± 2%, suggesting that this type of flour preserves high content of dietary fibre after digestion. The conceptual process design showed that 24.48 g of IMO are theoretically obtained from 53.24 g of plantain flour maltose. These results suggest that the rejected plantain pulp holds high potential as an ingredient for the production of prebiotic compounds such as IMO.