You all know my views on adding commercial yeast to sourdough. Add yeast and its not sourdough any more. When I was teaching people for an employment project some years backI experimented with hybrids and they most definitely inferior to naturally leavened loaves.
When you try to find out the reasons bakers add yeast they usually say because it shortens proving times and fits in with their baking schedules. Mr Lepard once said of a particular loaf that using all sourdough would be too strong for the bread’s delicate flavour. He might have a fine palate but I take that with a large pinch of salt (2%).
My own view is that people (not Mr Lepard of course) don’t have confidence in their starter.
But this isn’t a rant. I have a question. While doing a bit of web research on sourdough pizza bases I was directed to an entry on the Fresh Loaf where someone has posted a recipe for a “sourdough” pizza base that includes a pinch of yeast for each pizza. The dough goes on to prove in the fridge for two to three days. Can anyone give me a clue to the thinking behind yeasting a dough that’s going to prove for so long?
The PArtisan Baker 
Mick,
If we were talking bread I’d say the yeast was there to help the dough get some lift when it went to oven .A sourdough left for so long will change it’s ph level quite a bit I should think and being more ‘acidic’ is less likely to have the same rising power as on a shorter proof.It might also lose a bit of volume,
I’m with you though, don’t mix the two !!!!!
Speak to you soon
Rick
Blimey Rick you must have time on your hands posting on blogs. You got an apprentice or something?
Whatever else it doesn’t make any sense at all to me with pizza dough that’s proving that long.
See you soon!
That Fresh Loaf recipe almost sounds like some wierd combination of l’Ancienne technique plus sourdough (for flavour), assuming the dough was made using ice cold water and kept around fridge temperature: even at those low temps I reckon you’d still be getting fermentation thanks to the baker’s yeast, and the sourdough would just be adding acidity etc.
Course I could be talking a load of tosh, and the recipe’s simply a bit ‘screwy’…
My guess would be that the baker’s yeast possibly wakes up more quickly after the long retardation.
Several of Nils recipes are yeast hybrids, with much shorter proofing times than an all-levain loaf. They are still remarkable breads, even if the purists (like me) feel a shudder when the yeast goes in the bowl.
Matt
I have the greatest admiration for Nils. I carry him around with me everywhere on my kindle. But if I’m doing one of his hybrids I just leave the yeast out.
Bet you never thought you would hear me quote Peter Reinhart but he says that S. cerevisiae (commercial yeast) doesn’t like acidic conditions: “As the dough becomes more acidic, the yeast activity slows and the yeast cells begin to die. So, in a sense, it paves its way for its own demise.” (through the generation of acid.) “If a bread dough is allowed to acidify, it will eventually kill the S. cerevisiae yeast, and the dough will lose the ability to rise.”
S.exiguus and other wild yeasts found in sourdough can cope with acidic conditions.
So I’m afraid I can’t agree with any of you chaps (but I hope you are all coming to my party – only 11 days to go!!)
Looks to me like Varasano’s original recipe is more like ‘sourdoughed’ yeasted Mick, using a small amount of levain as a flavouring element.
That’s assuming I have tracked down the correct recipe in question!
No, it wasn’t. But I’m not wanting to point the finger. That’s why I put this on my own blog because if I put the question on the other person’s thread it’s immediately seen as an attack. I don’t mind being called an extremist but it gets a bit boring.
I just wondered if anyone understood the logic of adding yeast to a dough that was going into the fridge for maybe 48hrs
Ah, I was looking at this article, thought it might be the one and same
http://www.thefreshloaf.com/keyword/sourdough-pizza