How to carry forward yesterday's dough or get yeast from yesterday's dough

[nowdassaspicyameatball]

I have read some people say that some professional pizza makers use yesterday's pizza dough to make the current day's dough (so that whatever special yeast exists in yesterday's dough is carried forward to the current day's batch).  How is that done specifically?  Do I just take a small lump of yesterday's dough and mix it into the current day's ingredients and be sure not to add any yeast to the mix?  Or does it involve something more complicated?  Anyone know any rough ratios to use (e.g. how much of yesterday's dough to use compared to volume of ingredients for the current day's dough)?

Or is it that we need to use some kind of "yeast extraction" method for yesterday's dough in order to isolate the yeast for use with the current day's dough?

I am asking this because I have read stories of how some pizzerias use dough whose yeast has been derived from the first batch of dough they created when they opened for business many years ago (and they just kept the yeast alive by doing things like I am asking about above).  But, I can't find any specific steps that detail how in fact this is done.

Any advice, links, etc. would be greatly appreciated.

[Pete-zza]

nowdassaspicyameatball,

You might want to take a look at the Didier Rosada articles at http://web.archive.org/web/20040814193817/cafemeetingplace.com/archives/food3_apr2004.htm and at http://web.archive.org/web/20050829015510/www.cafemeetingplace.com/archives/food4_dec2004.htm. Note that the old dough in the first article is called Pre-fermented dough.

You might also take a look at Reply 5 at http://www.pizzamaking.com/forum/index.php/topic,20900.msg209378/topicseen.html#msg209378.

Peter

[nowdassaspicyameatball]

Pete-zza,

Thanks a lot for the links and the clarification as to what exactly this method is called.  I will read all the info in your links and see if I can pull this off or not.