AbstractThe changes in the levels of a number of oxidising and carbohydrate‐splitting enzymes of Amelonado cacao bean cotyledons during both large‐ and small‐scale fermentations were determined, on samples of beans taken after various periods of fermentation from the top and centre of heaps of different sizes. Inactivation of enzymes took place sooner in the top layer, where the temperature rise was more rapid, than at the centre. Enzyme levels started to diminish during the period when the beans were dying and continued until, after 3 days' fermentation, little or no activity was detectable. the results suggest that prolonging fermentation for several days after the beans are dead is neither necessary nor desirable.A germination inhibitor which was found in the pulp and testa of beans decreased in amount during ripening and disappeared during fermentation. Preliminary attempts were made to separate the inhibitor.