Fermentation samples were examined for yeasts and bacteria by simultaneous
cultivation on different media to increase the reliability of
data. In the case of yeasts, similar total populationswere found on plates
of eitherMEA or DRBC agar. Both media gave isolation of the same species
of yeasts at similar populations. For acetic acid bacteria, similar populations
and species were obtained on GYEA andWLNA. Although MRS
agar was used for the enumeration and isolation of lactic acid bacteria,
the two main species of acetic acid bacteria found in this study
(Gluconobacter frateurii and A. pasteurianus) grewwell on this medium
andwere easily distinguished by their colonymorphologies.WLNA also
supported the growth of Pantoea agglomerans that was sometimes
found at the commencement of fermentations, and Bacillus species
found in the late stages of some fermentations.