In an experiment to determine the effect of pre-culture conditions on the sensitivity of yeasts to glucose catabolite repression (commonly referred to as the glucose effect), the yeast species Saccharomyces uvarum (carlsbergensis) K19, was used. This species is from the collection of the Industrial Microbiology Laboratory of ENSAIA-INPL, Nancy France. The yeast cells were initially cultured on industrial wort with constant aeration throughout the culture period in the first instance and without aeration throughout the culture period in the second instance, creating aerobic and anaerobic conditions. The yeast cells from the two culture media were harvested and placed in media containing known concentrations of glucose and maltose as substrates and fermentations were carried out at 300C. Cells were harvested during exponential growth and the specific rate of fermentation (fermentation intensity) measured using the Warburg respirometer. Irrespective of initial and main culture media used, yeasts from anaerobic pre-culture media had significantly (P>0.05) lower fermentation intensities than those cultivated initially under aerobic conditions. Fermentation intensity of yeast cells on glucose after pre-culture on glucose is significantly (P< 0.05) lower for yeast cells grown under anaerobic conditions when compared to cells grown under aerobic conditions. Oxygen limitation during pre-culture growth of the yeast cells had significant (P< 0.05) effect on the glucose effect (catabolite repression) irrespective of carbon source used as substrate