restoring a starter??

What is your current feeding schedule?  perhaps with that we can figure out the problem.

Hi Mike

Im not the best person to write back but I thought I would just say from what I read, its pretty hard to kill a starter and only a few tings can actually do that. Im sure with regular feedings it should come up to scratch, after all sourdough is patience isn't it? Otherwise, starting a new one isn't so bad. Although 2 years is a long time and a lot of flavor .

You should be able to get a more detailed response from experienced bakers

Ghazi

I have a sourdough starter (from KAF) which I have maintained for nearly two years, with a now-complete ability to produce leavening.  I feed it about every 10 days with equal weights of AP flour, water, and old starter.  I let it sit for 1-2 hours at room temp, then back to the fridge.  It seems that there is only the retention of the flavor, with little, if any, yeast activity. I have clearly selected for the bacteria, and would like to add yeast  Is there something I can do other than add yeast to the pre-ferment?  I would .like to have a complete starter, rather than adding commercial yeast.  Any suggestions?  Thanks for your time.

Mike Acord

I think I see your problem, refrigerator tired-a-nitus.  Too much time in the fridge and not enough time (once a month or so) spent on the counter top above 24°C or 75°F to let the starter go through a full rise and fall cycle to keep it healthy.  

Cure, take out your oldest starter that you're working with.  Let it warm up and ferment on the counter top.  I would suggest putting the starter carefully and cleanly in a clean tall narrow glass so you can watch it and mark the level of growth/rise.  Put some tape up the side or find a sharpie and then let the starter ferment until it reaches peak expansion.  Mark that and the time it took to get there.   When it starts to fall back, feed it again and repeat the rising.  (When it falls back, make sure it smells yeasty or a little beery, if not the bacteria were raising the dough and the yeasts need more time to just sit there and ferment until it peaks from yeast.)  

The first time the starter peaks, it may take time but with each repeated feeding the yeast growing in the starter should be rising faster and stronger getting the peaking time under 12 hours.  When you get rise times back to where you want them.   Wait for the rise to fall back from peak, feed, and then let it rise about 1/3 to peak and then chill.  Should work out for you.  The whole idea is to lower pH or raise the acidity of the starter so you can maintain it easier.  That way over feeding will not become a problem.

If that first peak takes longer than 24 hrs add a teaspoon of cider vinegar or lemon juice (per 100g flour)  stir into the starter and do not discard.  Let it sit until it bubbles to peak and starts to fall back.  Include some vinegar or lemon juice in the next feeding from the start.  Taper off acid with each feeding as the starter responds with yeast growth.  

Mini