Xylitol as bio-product from the agro and forest biorefinery

VALLEJOS M.E.; AREA M. C.

Ch.12. in: Grumezescu, A.M. and Holban, A. M., Handbook of Food Bioengineering (Multi Volume SET I-XX), Volume II: Food Bioconversion, 1st Edition

Elsevier (Academic Press)

Lugar: Cambridge; Año: 2017; p. 411 - 432

Hemicelluloses fromhardwoods, canes, and grasses are mainly xylans which can be depolymerized intoxylose as primary carbon source for the bioproduction of xylitol. Xylitol isused as sweetening agent, and it can also be an important platform for sustainablebioproducts. A key point in xylitol production is the availability of xylosesolutions at low cost, which would facilitate the emergence of new markets andapplications. Xylitol can be industrially produced by the fermentation ofxylose extracted from hemicelluloses as an alternative to the expensivechemical process. In this context, wastes of agro- and forest- industries areinteresting alternatives. The production cost of xylitol on an industrial scalealso depends on the technologies used for xylose conversion and those for itsrecovery and purification. Improvements in biomass treatment, detoxificationand fermentation processes are needed to make xylitol productioncost-effective, opening new markets and creating new applications for it. Theaim of this chapter is to discuss several strategies for the extraction of thexylose from biomass, the detoxification of the hydrolyzed to obtain xylosesyrup to a relatively low cost, the critical factors for the fermentation ofxylose to xylitol, and the recovery of xylitol from fermentation broths.