Gerardus <nos...@allow.ed> wrote in
news:MPG.2a065451e...@news20.forteinc.com:
Active dry yeast, also called dry yeast, has some carbohydrates left
over from the manufacturing process. These carbohydrate reseves allow
the yeast to activate when it gets wet.
The common commercial yeast is Saccharomyces cerivisiae. The different
types of yeast in the store are merely variations of this yeast,
selected for the characteristics that the yeast producer wants in his
product.
Rapid rise yeast is a different organism from dry yeast, a different
strain of the basic yeaste. Think the difference between two different
Oncidium orchids. They may both be Onc., but they can be very different
in their size, color, leaf structure, etc. Same with yeast. The rapid
rise may be yeast, but it is a different plant from the dry yeast. It
has a shorter lag time and works faster, or at least produces more gas
faster, whether it reproduces faster than dry yeast is something I don't
know.
Gunpowder is another example. Pistol powder and shotgun powder are both
gunpowders, made from essentially the same ingredients. However, pistol
powder has to burn very rapidly, while shotgun powder burns slowly.
Pistol powder has to complete its burn within 2-6 inches of bullet
travel and usually has to contend with light bullets. A shotgun shot
charge can be as heavy as 2 ounces and has to reach terminal velocity in
26-32 inches of travel. The shotgun powder starts slowly and builds as
the shot charge gets moving. If you were to load pistol powder into a
shotgun shell, it might/would blow the barrel apart about 6-8 inches in
front of the chamber. (Don't ask me how I know this.)
The above doesn't apply to sourdough fermentation, which is a whole
different deal. If you are interested in sourdough, drop by the
sourdough group and have fun there. heh heh heh.
As far as I know, there is no baking powder in either yeast. If there
were, the label would say so, especially in Europe, where they tend to
be a bit tighter with their labelling than in the US.
Barry