How do I convert recipes?

This is my first experiment converting a recipe using commercial yeast to a sourdough one. I chose a recipe for Mushroom Bread from Carol Field's 'The Italian Baker'. 

The original recipe has 1 1/4 teaspoons of active dry yeast or 1/2 small cake (9g) fresh yeast. 

Ok so the range for converting is 20% to 40% starter to replace the yeast so I decided to go a bit higher in this experiment to a 45% preferment in the final dough. I was not sure of the effect on the dough of all that fresh fungi and I wanted a nice light bread. It is also fairly cool in my kitchen at the moment.

According to the recipe the two secrets of getting the most flavour into the bread are using the soaking water from the porcini and allowing the flavour to develop over long rises. The recipe uses a combination of dried and fresh porcini mushrooms. For the fresh mushrooms I used Swiss Brown mushrooms, because we can't get fresh porcini here in Oz. These mushrooms have a deeper and earthier flavour than white mushrooms, and their firm flesh means Swiss browns hold their shape well when cooked. 

I also found an olive oil with truffles which added just a bit more of that earthy flavour I love.

Added Ingredients:

4 to 6 dried porcini mushrooms

210g Fresh Mushrooms

1 teaspoon minced garlic

You start with soaking 4 to 6 dried porcini in the warm water (447g) for at least 1 hour, drain but save the liquid. You use this mushroom water after straining through cheesecloth 2 or 3 times, to add flavour to each preferment and the final dough. Roughly chop the porcini and pat dry. 

Slice thickly and sauté the fresh mushrooms with the minced garlic and as little of the oil as possible and set aside to cool.

Day 1 evening - 1st Preferment Build                                                                                            

Starter 14g    50%

Flour   27g  100%

Water 19g     70%

Total 1st build  59g                                        

Starter 1st build  59g  61%

Flour   97g   100%

Water   68g   70%

Total 2nd Build 225g                                      

Dough Formula                                                                                                                                  

Flour 500g 100%

Water 360g 72%

Salt      15g  3%

Preferment 2nd Build 225   45%

Diastatic Malt 10    5g   1% 

(This is Malt blended with Bread Flour at 1g Malt to 10g flour. Diastatic Malt is normally added at 0.1% of flour weight)

Olive Oil (with truffles) 20g  4%

chopped porcini (mixed into dough)

Fresh Mushroom    200g  40% (folded in last)

Total  1328g

I mixed up the dough stirred in the re-hydrated chopped porcini covered the bowl and then put the lot into the fridge overnight. 

Day 3 - morning 

Take out the dough and fold once and return to the fridge.

Day 3 - evening 

Take out the dough let it warm to room temperature.

Folded it once every hour for four hours. 

The sautéed mushrooms were chopped in half and folded in last just before shaping

The dough was patted down into a rough rectangle shape and half the chopped mushrooms scattered on the dough. The dough is then rolled up tucking in the ends and then shaped into a ball and rested 10 minutes. The dough was patted down again and the rest of the mushrooms scattered and rolled up in the dough again tucking in the ends.

Shape into a ball or oval, being careful not to expose the mushrooms. I decided on one large boule and placed it in a cane banneton which I put inside a plastic bag and popped the lot into my microwave to rise. I have found on cold nights the microwave with the door slightly open so the light is on, works quite well as a proofing box and keeps the dough out of drafts.

After an hour or so when the dough had risen I put the banneton back in the fridge for baking in the morning.

The end result:

This experiment certainly worked. The bread was nice and light with delicious moist mushroom bits with a hint of garlic. 

I loved this bread and will certainly make it again 

Semolina Fennel Seed Bread with Cranberries and mixed seeds
My take on converting this very tasty bread based on Susan’s (Wild Yeast recipe). I went for 47% preferment in the final dough because it is so cold in my kitchen at present and I was not sure how well the starter would do. 

I also chose to use a mix of Pepitas, Pine Nuts and Sunflower kernels for my seed mix, mainly because that is what I had in the cupboard.

I mixed up this dough in the morning with the cranberries, fennel and mixed seeds and covered the bowl with a plastic bag and threw it in the fridge till I got home from work that night.  

I pulled the dough out to warm up. I folded it every hour for 4 hours and let it rest on the kitchen bench covered with a plastic bag in-between folds. The loaf was then shaped and let rest in a cane banneton for another hour before being popped back in the fridge overnight, ready for baking in the morning.

Here is the formula I used: