Bioethanol subproducts as a basis of plant biorefinery

The philosophy of our research is built on the behaviour of non-sugar compounds from biomass during ethanolic fermentation.
Saccharomyces cerevisiae, industrially used to bioconvert sugar into ethanol under anaerobic conditions, assimilates some compounds present in the fermentable juice (proteins, amino acids,...). But others compounds are not used by the yeast. They leave in the vinasse after ethanol distillation and are thus concentrated by the process. Our purpose is to discuss the behaviour of betaine, saponins and raffinose in sugar juices (raw juice, thin juice, thick juice) and in vinasse after ethanolic fermentation. An attention will be given to some high added value products (like betaine) and the potentialities to use fermentation as a tool of purification in white chemistry.