The yeast cultivation by CRBF was carried for 39 days, during which 38 batches were completed (Fig. 1). Each batch consumed more than 90% glucose, and almost all of them did have less than 1 g/L remaining at the end. The biomass content in the reactor increased steadily in the first eight batches (media A and B), reaching approx. 3 g/L. Batches in medium C presented unstable biomass measurements, and biomass growth stopped almost entirely in batches carried out in media D and E, causing a decrease in biomass concentration as each batch removed non-flocculated biomass. In medium E, each batch started and ended with approx. 2 g/L of biomass, resulting in a near-zero growth rate (acknowledging data spread). However, glucose continued to be consumed (Fig. 2). After seven batches in medium E, the culture was reverted to medium C to allow biomass growth under less stressful conditions. The adaptation protocol was resumed, changing to media D and E after four successive batches in each medium. Biomass concentration increased slightly in the last batches made in medium D, but descended in subsequent batches in medium E. Glucose exhibited high variability, probably due to dilution by broth exchange, detection of additional reducing carbohydrates in the medium and possible interference by EDTA on DNS method.