Alcoholic Fermentation of beet molasses: study on stillage recycle

Summary Stillage recycle in beet molasses alcoholic fermentation can be lower the production costs by a decrease of energy requirements for waste water treatment but it becomes necessary to optimise, separately, the sugar and non sugar contents of the wort. It is shown that the increase of the wort osmolality, linked to stillage recycle disturbs yeast metabolism above 1,5 osmol. The observed inhibition which is dependent on both sugar and non sugar concentrations leads to an apparent link between yeast behaviour and the dry matter percent of the worts.