The Fresh Loaf

News & Information for Amateur Bakers and Artisan Bread Enthusiasts

Collapse and re-growth cycles after starter refreshment

Martin Crossley's picture
Martin Crossley

Collapse and re-growth cycles after starter refreshment

This really interested me... I took a time-lapse video of the ten hour period after a [1:1:1] refreshment of my 2 week-old wheat starter (3:1 white/wholemeal),

https://youtu.be/nETA5QpmgWA

The first phase was as expected: a near-exponential growth in volume that peaked out after 3hrs (at 22 deg C) and then 'held' for 20-30 mins.

The next part really surprised me, with two or more apparent cycles of collapse and regrowth. Anyone got any idea what is going on to cause this? LAB digestion of wheat releasing food for the yeast?

Anyhow I'm rather intrigued to see what point is best to use the starter for volume/flavouring of a final dough.

Ideas, comments, suggestions welcome :)

MARTIN

Mini Oven's picture
Mini Oven

is normal.  What is happening is that without stirring the gluten's ability to stretch and trap gas has reached a maximin peak, breaks and collapses onto itself.  This collapsing folds the gluten strands (and can be further emphasised with stirring or folding) giving the gluten a second chance to extend itself and trap more gas.  This can go on until the food is completely gone for the gas making yeasts or the gas trapping gluten wears out, which ever comes first.  

Maybe you can see how this applies to bread dough as well.  The difference being not to let the dough ferment to peaking before shaping for a final rise.

On the subject of the starter...  May I suggest feeding it more flour?  Feeding every 3 hours is worse than pet sitting.  At least pets go to sleep.  Feed it enough flour so that your first peak is at 8  hours.  Give it a 4 hrs rest approximately and then put it on a 12 hour feeding schedule.  You will have to play around with the amounts increasing the water and flour and giving it more time to peak.   Have fun.  :)

Mini

tmccarthy27's picture
tmccarthy27

Mini, I always love your comments.... but I do not understand this comment.  The first part: add flour... for a higher flour to water ratio?  Okay, (for example:  ___ Flour to  ___Water ?) so that it peaks in 8 hours.   But with this percentage you feed your starter every 12 hours?  I don't get it. 

Martin Crossley's picture
Martin Crossley

Hi there TMC - I think what Mini is talking about in the first bit is to make the starter expand more slowly by reducing the hydration, or the proportion of seed culture. The 12hrs comes from it peaking in 8hrs and then having a 4hr 'rest' before feeding - i.e. 8 + 4 = 12.

In fact I don't keep my starter on a 'feeding regime' at all: I just reserve 40g or so of the fully-refreshed production leaven just before I mix it into the dough.

My full production cycle (depending on what final hydration dough I am going for) goes something like this:

sourdough system