The Fresh Loaf

News & Information for Amateur Bakers and Artisan Bread Enthusiasts

Why does my leaven sink?

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Jaymo's picture
Jaymo

Why does my leaven sink?

I'm a new baker working on the Tartine basic loaf. I was going to bake yesterday, so followed the instructions "the night before you plan to mix the dough...". The next morning, about ten hours after feeding the starter, the leaven sank when I put it in a bowl of water. The kitchen temperature was about 72F. I let it stand another couple hours; same result. I let it stand another couple hours; same result. I let it stand another couple hours; same result. You get the idea... I re-fed last night, with the same results this morning.

I baked last week, and failed to test the leaven this way. The resultant loaves were very tasty, but very dense and very sour; probably because I let the bulk fermentation go on so long in an attempt to get some volume increase, which was ultimately minimal.

Any ideas?

mrfrost's picture
mrfrost

Next time, try observing(and testing) it a little earlier, like about 5-6 hours or so. Reads like it was well past it's peak at the 10 hour mark. Yes, reads like you possibly were over proofing on your bulk(and final) fermentations.

p.s. How old is your starter? Have you baked with it(successfully) before?

Jaymo's picture
Jaymo

I was wondering if I could have missed the peak. Yesterday, I bought some Rapunzel Organic active dry yeast, and mixed a bit in the the leaven that seemed stuck, along with a little (25g?) fresh white flour. After a few hours, it was floating. So I at midnight I bifurcated the batch, and made a fresh batch of leaven with 1 Tbsp of the stuff that was passing the float test with 200g cool (70F?)water, 100g white flour, and 100g whole wheat flour, and put the rest of the float-test-passing leaven in the fridge. The kitchen is at about 70-72F. At 8:30AM, the leaven I'd mixed at midnight sank when put in cold water, as did the stuff I'd put in the fridge.

 

My starter is about three weeks old now, and I've only baked once before: last weekend, when I produced the tasty, very dense, very sour bread I described above.

 

So how do I proceed from here to be able to bake today?. The work week starts again with a vengence tomorrow. :-(   Replace half the leaven with fresh fuel? More yeast?

mrfrost's picture
mrfrost

Personally, I'm in doubt about the readiness of your starter and it's ability to be used for baking presently. However, the only way to know is to have observed it's behavior over it's short lifetime. When getting these things started, it is best to be able to observe the starter's activity every couple of hours or so. Depending on the hydration level(and temperature), it should be at least doubling every 4 - 8 hours or so(at least).

As for baking for today, I would suggest sticking to one of your favorite, proven recipes, that you have been successful with in the past.

As for the Tartine recipe, I would encourage you to get a little bit more familiar with your starter, and baking with starters, in general. Having never tried Tartine-I consider it and "advanced" recipe- I'm not in position on how to advise on it, and using your "hybrid" starter.

Good luck. Maybe someone else will chime in.

Jaymo's picture
Jaymo

MrFrost, What do you mean when you say "doubling every 4-8 hours"? Is that the volume of the starter, or the population of the yeast  colony?

FlourChild's picture
FlourChild

Sounds to me like your starter has too much acid and not enough yeast.  In my experience this comes from not feeding the starter enough or freqently enough. 

If you convert to a firm starter it may be easier to read the peak- in a firm starter, feed whenever it domes and is just beginning to dent, dimple or flatten, or as close to that time as possible.  As you get a feel for how often and how much to feed your starter, you can try things such as altering the amount of seed that you use, altering temperature, etc., to control the timing of feeds. 

Once you get it balanced and active, you can switch back to a liquid starter if you like (or just have the bread builds be liquid and keep the ongoing culture at a firmer hydration).

I agree, the Tartine country loaf is an advanced bread to make- it's sort of funny, because the book seems to be written on a more basic level, but it takes some real practice and skill to figure out both starter timing/feeding and how to work with such a high-hydration dough.

Jaymo's picture
Jaymo

MrFrost and FourChild, thanks much for the input, particularly about Tartine's country loaf. As I'm demonstrating to the best of my ability, I have  no clue what I'm doing, and am enjoying  the process so far. It seems I've jumped in over my head, perhaps. I'd be happy to  be pointed to a book/method more appropriate to my knowledge level, if you have any suggestions.

In the mean time, I'm going to start feeding my starter twice a day, and to try to watch it more closely to see if I can get a better understanding of its lifestyle.

Jaymo's picture
Jaymo

FlourChild, your instincts seem to be on. I tasted the two batches I have going, and the one that was in the fridge last night was really sour. So I just put 25g of it with 50g cool water, and 50g of flour. I'm just cooking and gardening today, so I'll be able to watch it carefully.

The stuff I did this to this morning at 10 was also sour-tasting, although less so.

Should I do the same thing I did to the other batch? Is this a good feeding method; 20% starter-40% water-40% flour? The kitchen is at 82F today, even with the A/C on.

Does it matter what the total mass of the critter is? I don't want to be chincy, but I don't want to be wasteful, either...

FlourChild's picture
FlourChild

82 is quite warm- can you find any place cooler to keep your starter?  It will ferment almost twice as fast at 82 as it would at 68F.  Flavor-wise, I try to keep my starter at 70F, I've done some tests and the flavors produced at that temp suit me best.

I don't have a lot of experience with maintaining a liquid starter- I prefer the firmer hydration, though I'll make the adjustments for a bread build at whatever hydration the recipe calls for.  Leaving hydration out of the equation, I can tell you that my starter gets 45g of KAF AP every twelve hours at 70F and my "seed" only has 6.25g of flour in it.  This translates to 10g seed, 45g flour and 25g water.

As for the size of your starter, larger batches ferment differently than smaller ones, and there is a limit, I think, to how small you can go.  But mine is pretty small and it still provides more than enough seed for several bread builds from any one 80g jar of starter.

I've read that commercial yeast doesn't survive well in a sourdough starter because of the high acidity, but it works just fine to add some to a bread recipe, where the starter is generally diluted enough to not pose a problem to the instant yeast.

Perhaps someone with more experience in feeding a liquid starter will chime in :)

 

Jaymo's picture
Jaymo

Yes; I can move the starter to the basement. I'll do that.

It sounds like our maintained masses are about the same size, but that you use 2:1 flour:water and less seed, compared to my addittion of equal parts flour:water , and a bit more seed? It that what you're referring to as a "liquid" starter?

 

Jaymo's picture
Jaymo

OK, I just applied your formula to one of my batches: 11g seed, 45g Bob's unbleached white flour, and 25g water. That's a really different creature than my other, wetter one. It will be interesting to see how they behave side-by-side.

Do you taste your seed, or do you go by appearance? I noticed that one batch was much more sour than the other, and that the less-sour one had a more pronounced floury taste. Can you tell where in the process you are by taste? I also noticed that the fresh batch of liquid seed tasted very floury, with only a faint sourness. But maybe it's just me tasting what I expect to taste. 

FlourChild's picture
FlourChild

11:45:45 is still quite different from 10:45:25 (seed:flour:water).  Basically, mine is a 55% hydration dough and yours is a 100% hydration dough- one is firm and gets kneaded like a bread dough, while the other is a batter that gets stirred.

Do I taste my starter?  Not very often.  I go by smell and volume and shape of the dough.  No matter how much it's fed or what the temp, a firm starter is ready to feed when it has domed and then just begun to flatten, dimple or recede.  There's an easy to see, visual cue, so tasting isn't so important.  When I referred  to a favorite temp/flavor, that came from baking lots of little test rolls, each fermented at a different temp, and choosing the flavor that suited me.

Why does your starter taste different at different times?  It goes through a cycle.  When you first feed it with flour and water, it will be very diluted and mild, tasting mostly of flour.  As time goes by, the wild yeast and acid-producing bacteria go to work multiplying and producing their by-products (such as carbon dioxide and lactic acid, but there are others as well).  This will continue until the yeast run out of food and slow their activity- this can be seen by the flattening or receding of the starter- but the acid-producing bacteria keep going.  So after the starter recedes (and I think liquid starters do the same thing- rise while the yeast are growing and then recede at the point they should be fed), it gets progressively more acidic, with comparatively less yeast activity.

So my advice would be to keep your starter cool and watch it as best you can, feeding it whenever it peaks and is just beginning to deflate.  In a glass jar, a liquid starter will rise and then fall, leaving a high water mark.  You want to feed it before it leaves much of a high water mark.  Once you feel you have the right feeding schedule for a given temp, and that you are regularly coming close to feeding it at the peak volume, then try the Tartine bread again, but lower the hydration to 68-70%.  Once all that is worked through, begin increasing hydration.

Jaymo's picture
Jaymo

I mis-spoke with the second "45". I should have said 11:45:25. I just missed the 10g seed by a gram, and kept the rest the same. I've moved the starters to the basement, and am peering at them every hour or so. I haven't measured the temp down there yet...

FlourChild's picture
FlourChild

Ah, so now you have both a firm and a liquid starter!  Feed them when they peak, or just after, and after a few feeds you'll be on your way to a healthier, more balanced starter and have gained a little skill as well :)  Good luck.