Yeast in Kombucha

[Guest guest]

Good Morning:

I read the thread on yeast (too little or too much) and thought the

following would be helpful:

" The microbiology of the Kombucha colony is as diverse as the various growers.

Some colonies have only one yeast, some two, some three, some four, and it is

not yet known how many yeasts the ferment will support. As for bacteria, it will

support a broad spectrum as well - some with two, some with three, some with

four, some with five, some with as many as ten species. Is ten the limit of

bacteria that can be isolated in a single ferment? We don't think so. Since the

process of fermenting Kombucha can best be described as selective spoilage, the

choice of yeast and bacteria are important to the Kombucha ferment.

Investigation of the yeast in Kombucha over the past decade has been quite

productive. Probably the most informative paper on this topic was " The yeast

spectrum of the tea fungus Kombucha, " Mayser P, Fromme , Leitzmann C,

Grunder K, (Mycoses 38 (1995) 38: 289-295). These investigators reported only on

the yeasts in the Kombucha ferment/colony. They discovered that there were no

less than seven possible yeast genera combinations. In their study they examined

34 colonies from around Germany and proved nine single yeast isolates (including

Candida albicans), 19 double yeast isolates, four triple yeast isolates, and one

quadruple yeast isolate. This is an excellent paper and an excellent study that

I highly recommend for reading, even if your local library needs to order a copy

for you. In their work, they isolated and identified Brettanomyces,

Zygosaccharomyces, Saccharomyces, Apiculatus, Candida Krusei, Candida kifir, and

Candida albicans. "

The combination of yeast and bacteria in a ferment will determine the

fermentation time and the ratio of sugar acids to acetic acid. Each grower has a

unique ferment based on their own environment and brewing methods. I hope that

helps the understanding that there really are not too many or too few yeasts in

a Kombucha ferment.

Mike Roussin

mike@...