Additives
and Herbal Teas
or
"If it ain't broke don't fix it"
A
Letter to a Kombucha Tea Grower
By
Norbert Hoffmann
Hi
Ari,
you asked my opinion about adding acidophilus bacteria or
other additives to Kombucha Tea. First of all, there are no long-term studies of
the effects of additives or use of substrates other than black or green tea on
K.T. and, furthermore, we don't have any easy comprehensive test instruments
available that would tell us that we have a good healthy culture. Measuring pH
and ketones plus our observations - does it look, taste and smell OK, did I get
sick from it the next morning - is about all the average K.T. user can do. We
don't even know for sure which the essential components are. Many say that
glucuronic acid is the most important factor while others believe that acetic
acid plays a role also. We know of a number of other components but we are not
sure exactly what they contribute to the effectiveness of K.T. It is quite
possible that several of the factors have to be present at the same time to make
K.T. the beneficial remedy it is - similar to the way many medicinal plants
work.
Since we are lacking long-term studies and tests, it is my
strong opinion that we should always have an ongoing culture using the standard
recipe and that any experimentation should be done parallel to that. Since we
don't know what adding new bacteria like acidophilus, substituting or
supplementing black or green tea with other teas having high amounts of
essential oils or using flavoring agents like ginger will do to the culture
long-term, we can only go by what we know about microorganisms and their
behavior.
Whenever several different populations of microorganisms
co-exist, you often have survival of the fittest or survival of the ones that
get along the best. Many times there is a rather delicate balance between the
different organisms and the environment. Change any of the factors and the
individual populations of the various organisms may be affected - temporarily or
permanently.
To give an example: There are approximately twice as many
microorganisms in and on our body than there are body cells. Usually they live
together happily and harmoniously without causing any harm. Some of them are
opportunistic microorganisms that may be dangerous if they were given free
reign. But the environment including our body defenses and other microorganisms
hold them in check. In our mouth there is a large number of different organisms all
the time: various types of streptococcus, lactobacillus, actinomyces,
bacteroides, fusobacterium, treponema, corynebacterium and last not least
candida. Pretty scary when you see the list for the first time. But these
microorganisms in our mouth usually live there without harming us. But we all
know what candida can do when it goes unchecked. Other bacteria may do damage to
the teeth enamel if the environment changes - for example a change in acidity.
The situation is very similar in most other places of our body, the intestinal
tract, urinary tract, respiratory systems etc. (Tortora et al)
Sometimes, when certain microorganisms come together damaging
or even deadly effects may result. One extreme example is the mycoplasma
fermentans, the smallest bacteria that is capable of existing outside of cells.
When this bacteria infects cultured cells along with the HIV virus, the cells
have been found to die more readily compared with cells infected by the virus
alone. (Tortora et al) In this case it is a virus and a bacteria working
together, in other cases it may be various types of bacteria or yeasts. There
have been a lot of discoveries made in the field of microbiology over the years
but much more remains to be learned.
We know that essential oils retard the growth of
microorganisms. If we use teas with high content of these oils the population of
some of the microorganisms may actually be reduced. This is probably OK for a
while. If we would continue to use these as growth media over a long period of
time, the culture might get changed permanently as a result. Perhaps the
bacterium glucuronicum might get extinguished. We don't really know for sure.
Adding the acidophilus bacteria may be quite harmless or even beneficial - or it
may have a damaging effect. Another factor influencing the growth of
microorganisms are the essential building blocks we provide through the tea in
addition to the sugar, the water and its trace elements. Black or green tea is
high in certain organic compounds containing nitrogen and other important
elements needed for microorganism growth. Some herbal teas may have considerably
less.
Reiss experimented with various substrates. Using black tea
resulted in 2.25 grams of gluconic acid per liter (~quart) after 2 weeks of
fermentation, while peppermint tea resulted in only 0.04 grams. (quoted by Frank
G.) In other words, the culture with black tea produced 54 times more gluconic
acid. Now, note that this is not glucuronic acid but gluconic acid.
Nevertheless, it still shows the effects of an herbal tea with a high content of
essential oils on the amount of an organic acid being produced. And from the
significantly smaller amount of organic acids produced with peppermint tea, we
can conclude that the microorganisms producing them are severely affected either
by the high essential oil content of the tea or by the smaller amount of
critical building blocks or both. It is probably OK to continue using peppermint
tea (or other herbal teas for that matter) for a few weeks. Change back to black
tea and the organisms probably bounce back. Günther Frank always says that K.T.
is pretty robust. But do it for a longer period of time and some of the strains
might get weaker and weaker and eventually die out. As a result you probably no
longer have Kombucha Tea.
Originally, Günther was a strong opponent of using teas with
high essential oil content. He has since modified his opinion to some extent and
doesn't see it quite as narrowly as he used to as long as herbal teas are added
to black or green tea and not substituted (in a personal communication about 1
1/2 years ago). For example, Günther's wife Rosemarie makes delicious K.T. with
lemon balm in summer. I had the opportunity to sample it several times during my
visits. But, on the other hand, he and his wife always use the standard mixture
for ongoing cultures and any experimentation or variations are done in parallel
like I suggested above.
Well, I hope this lengthy comment helps. Let me know if you
have any questions or feedback.
Have a nice day.
Norbert
Literature:
Frank G. Kombucha - Healthy Beverage and Natural Remedy from
the Far East. Steyr: Publ. House Ennsthaler. 1994. Pg. 29.
Tortora G., Funke B., Case C. Microbiology. Fifth Edition.
Redwood City: Benjamin/Cummings Publ. Co. 1995.
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