The additional fermentation conditions, such as nutrient con-centration (0–2 g L1 NaHCO3, 2–10 gL1 yeast extract) and agitation speed (0–300rpm)were optimized by means of a factorial design. The time of fermentation was 96h, with
aliquots being taken at in tervals of 6 h in order to accompany the consumption of the
sugars and the production of SA.