Towards a biorefinery processing waste from plantain agro-industry: process development for the production of an isomalto-oligosaccharide syrup from rejected unripe plantain fruits

Abstract

The aim of this work was to evaluate the production of isomaltooligosaccharides (IMO) from rejected unripe plantain fruits (Musa AAB Simmonds) on a laboratory scale and assess IMO syrup production for a large scale through process simulation. The enzymatic activity of the commercial preparation of -glucosidase was 936.23 ± 0.71 U/mL. The MichaelisMenten model was used to adjust the experimental data, and its kinetic parameters were used in the simulation. Maximum IMO production from a mixture of 18% plantain flour with a starch content of 84% was obtained for a reaction of 6 h in the transglycosylation step (29 ± 3 g/L isomaltotetraose and 8 ± 3 g/L isomaltopentaose). The best scenario to produce IMO showed a net present value of $ 459,000. Results suggest that IMO syrup production for a large scale, including an integrated production of single cell protein considering a batch size greater than 11,126 kg rejected fruits is feasible, if the production costs associated with labor are reduced and the selling price of the products increases according to the variation of the market. This work demonstrated that the rejected plantain pulp exhibits high potential as an ingredient to produce prebiotic compounds such as IMO.