Roy wrote:
>>Which also makes me think that yes this culture does contain *some*
>
> commercial yeast
>
> A natural culture can never contain commercial yeast ,but strains
> related to the same genus can exist in natural starters and this what
> confuses some investigators who that insist that bakers yeast ( or
> they immediately recognize as S. cereviseae) cannot survive in the
> acidic conditions of the starters. That is if the kept on thinking
> that saccharomyces cerevisease is just bakers yeast and nothing else.
> But there are more than 40 types of Saccharomyces and bakes yeast is
> just one, another one in wine, for spirits and for beer etc., more on
> the wild yeast area which are tolerant to adverse conditions than
> the cultured ones used in normal baking and beverages and was one
> time re classified under the name saccharomyces cerevisieae!
> Therefore the mildness of some starters is caused by the presence of
> these species not necessarily the Candida milliere associated with San
> Francisco., or the population density of other yeast surpass the
> candida milliere.
> Now these other saccharomyces are not that acid tolerant like the C.
> milliere, but exist only in less acidic conditions.
> Therefore this seems to coincide with the French investigators
> findings( in my previous posts) that subspecies of Saccharomyces
> cereviseae can dominate in milder starters which is common in French
> sourdoughs and classified under the same name due to similar
> microbiological characteristics.. Other species of yeast were also
> found not belonging t the Saccharomyces.
> But there are some strains that Candida millere is the dominant yeast
> and its usually in the acidic type of French levain which coincides
> with organisms found in the San Francisco sourdough and other
> related more acidic culture characteristics.
>
> Be reminded that yeast classification is ever evolving and that
> confuses layman and even scientific professionals in other fields who
> want to get a consistent classification in this particular microbe when
> they encounter this in their research work. This reason may have
> affected earlier investigators conclusion that all strains of
> saccharomyces cereviseae cannot survive in the acidic nature of
> sourdough cultures which is erroneous as what later investigator founds
> out elsewhere.
>
>
>>A number of microbioligists have tested starters and found that bakers
>
> yeast will not survive more than two refreshments in a starter. The
> acidity is high enough >that bakers yeast can not survive.
> Again I reiterate that....
> Generally bakers yeast cannot survive extreme acidic conditions; but
> there are yeast strains belonging to the same species that are hardy
> enough and incidentally they are classified as saccharomyces
> cerevisiae. Which I mentioned above.
> Besides bakers who added yeast in the sourdough place it on the dough
> preparation side which has milder pH conditions and never in the
> starter side( which is more acidic).
>
> I think this what should the people of Carl Sourdough Starters to look
> into , and investigate the nature of their culture flora and establish
> the population density of different yeasts species that can coexist n
> their culture like what the French investigators did with their Levain
> ( as they cannot understand previously )why in many parts of France
> the natural sourdough is milder while in certain areas its more acidic
> .And bakers and consumers there noticed that their bread sometimes
> fluctuates in flavor and taste when its known to be made wholly from
> natural starters that had been maintained for generations.
> And not just assume that all sourdough cultures is populated by only
> two microbes:
> The candida milliere and the lactobacilli L brevis variety Lindniere(
> Aka L. Sanfranciscensis).
> It must not be forgotten that French flour had moderate ash content
> that is similar with the American clear flours and seldom use lower ash
> flours for breadmaking but only for pastry anc cake baking.
>
> Sourdough enthusiasts should not have their eyes glazed by the stature
> of the earlier investigator like Kline, Sugihara, Gantzle etc who
> only focus their attention on the usual tandem of L San Francisco and C
> milliere. And forget (or not believe ) other equally competent but not
> popular researchers findings (whose works were never published in
> English language) and discovered other critters that can exist also in
> natural sourdough cultures.
> Besides it must not be forgotten that aside from the Saccharomyces
> there are other specie like the hansenula, torupsis and pichia that can
> exist also in natural starters and that can also affect the variability
> of sourdough tastes.
> Roy
>
I think if you trace Jean Wood's statement back, you will see that she
said that the bread machine recipe that was posted using Carl's starter
is what contains the commercial yeast, not the starter itself,
Ellen