The Fresh Loaf

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The Not-So-Sour Sourdough Experiment

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firepit's picture

The Not-So-Sour Sourdough Experiment


The Goal:

The idea for this test came from a thread by KipperCat asking about how to make a less sour sourdough. There was a general consensus in the thread that starter maintenance routines (feeding ratios and hydration) would have a small effect on the sour aspect of sourdough while varying the rise and proofing times would have a much more pronounced effect. Bill suggested an experiment, and as I was planning on baking a couple of loaves, I gave it a shot.


The Process:

I began the process by pulling Leon, my 100% hydration starter from the fridge on Wednesday and feeding it as I usually do -- 1:4:4 (in this particular case, one ounce starter, four ounces of water, four ounces of KA AP flour), once a day. This starter is very active, and after the Thursday AM feeding he was easily doubling within about 3 hours...I stir him down a couple of times during the day and he just rises right back up, so he seems content.


On Friday morning I set out to create two two-pound sourdough loaves, staying close to the basic sourdough recipe in The BBA using my starter as the base instead of his barm.


<tangential rant>

The only real pet-peeve I have with the BBA is that all of his measurements are in ounces. Why? It isn't that hard to provide both ounces and grams, and you can be more accurate with the grams...He has measurements like ".22 ounces" in there -- who has a scale that is accurate to a hundredth of an ounce?! anyway, As I build his recipes, I convert the measurements to grams so that when I come back the second time I'm not still frustrated. All of this is to say that from here on out most of my measurements will be in grams.

</tangential rant>


I fed 100 grams of my starter with about ~60 grams of water and 200 grams of flour, leaving me with a freshly fed starter that should have the same hydration level (~70%) as Reinhart's firm starter, scaled up a bit to be able to make a total of four pounds of bread. As directed, I covered the starter and left it on the counter to feast for a few hours.


After 3 hours the starter had easily doubled in size, so I moved it to the fridge until Saturday AM.


Saturday morning I pulled the starter from the fridge, allowed it to come to room temperature and started building the final dough. My mixer doesn't handle 4 pounds of dough well, so I divided the starter exactly in half, and then went through the build process twice, adding exactly the same amount of flour, salt and water, by weight, to each batch -- since I was striving for identical loaves over perfect loaves, I measured all the water going into the first loaf, then added exactly that much to the second loaf, regardless of consistency. Fortunately, since everything else about the process was identical, the water amount was just about right both times, too. I also mixed, kneaded, rested, and kneaded each batch for the same amount of time, trying to ensure that everything about these two loaves was identical thus far. The one difference I did allow here is that I used warm water (as directed by the BBA) for the "fast" loaf and I used cooler water for the "slow" loaf. At the end of kneading, the fast loaf registered at 82 degrees, the slow loaf about 5 degrees less.


The fast loaf was placed in an oiled bowl and left on the kitchen table to rise, with the ambient temperature varying around 75 degrees. The slow loaf was placed on top of a glass bowl sitting in a cooler above a layer of ice, with the temperature staying somewhere around 50 degrees.


Three hours later, the fast loaf had doubled, so I shaped it and returned it to its "warm" environs. As hoped, the fast loaf wasn't showing much progress at all.


Another two hours passed, and the fast loaf was ready to go. I fired up the oven, butchered the scoring, and baked.


By 4 PM (7.5 hours of rise time), the slow loaf had about doubled, so I pulled it out, shaped it, moved it back to the cooler and then headed out to dinner. Six hours later, it was time to cook. I pulled the dough from the cooler and fired up the oven again. About a half and hour later, the second loaf hit the fire.


Short summary:

Two identically handled loaves, one with a total of 5 hours of bench time, one with a bit more than 13 hours.



1) Both loaves are still far to dense. I am pretty sure my starter is just fine, so I'll be upping the hydration of the final dough the next time around.

2) It was a foolish mistake to take the slow loaf from the cooler and have it in the oven a 1/2 hour later, but I didn't want to be up all night, so I rushed it. The overall results would have been better had I left the loaf come up to room temperature over an extra hour or so instead of putting the cold dough into the oven...

3) ...finally, the flavor result.  After tasting each loaf I can conclusively say that there is virtually no difference in flavor between the two - both are only ever-so-faintly sour, which is not what I'm going for. So I'm surprised - the extra time for the rise and the proof didn't affect the flavor.


So what next? Two things:

1) I'm sure that what Bill and Brotkunst are saying is on the mark, so I'm undaunted. I will try this experiment again (but not next weekend - family is in town so I don't have as much time to fiddle)

2) I suspect there may be all sorts of ways that the density and the flavor are intertwined - perceptually, from a surface-area standpoint, what the density says about the flour and the yeast and timing...all that stuff. So for the short-term I'm going to focus on getting a single loaf of sourdough to come out well, then I'll get back to worrying about the flavors...


bwraith's picture


That's an interesting experiment. As I mentioned, I have not really tried it systematically like this, but one of these days I'll go after it and let you know.

I have a couple of thoughts.

One, you have a very fast rising starter. My starter would take about 6 hours to double from a 1:4:4 feeding at 75F. At 60F, I would expect the recipe wouldn't really work for me. I'd probably have to let it rise for more than a day, and with the acid levels delivered by the levain, I bet it would lose steam because of the gluten not holding up for that long.

I wonder if your faster rising culture is somehow inherently different from what I'm used to here, and maybe it's just more mild.

I noticed that you let the levain double and then refrigerate it, which is along the lines of the BBA Basic Sourdough instructions. One thing you could try is punching down the levain and letting it rise for another few hours at room temperature before you refrigerate it. That's one thing I tried that seemed to yield a more sour flavor, which for me wasn't what I prefer, so I never repeated the process.

This might not be even close to right, but with your fast rising starter, I wonder if you need to do things you might do with a yeasted bread to lengthen the fermentation and improve the flavor. For example, maybe you need to let your preferments ripen longer. Maybe you need to do more folding and actually "punch down" your dough and let it rise a second time during the bulk fermentation. In other words, if you have strong leavening capability in your starter culture, maybe you need to deflate the dough and let it ferment longer to get more flavor.

As far as getting a lighter loaf, I would expect 70 or 75% hydration to work very well with my KA flours, whether AP or bread flour. However, I've found that a fold or two at 30-60 minute intervals makes a tremendous difference - more than kneading at the beginning.

Good luck finding more sour results. Although my own preference is for less sour, more mild bread, it's still very interesting to explore how to make it sour. For me, I suppose whatever I learn would be used to "do the opposite".



KipperCat's picture

Well, I haven't baked any sourdough, so I won't be offended if you don't read further.  I'm not surprised that a 13 hour rise in the cooler wouldn't produce a very different flavor than the shorter rise at room temperature.  I think that you either need a few days in the cooler or fridge, or, preferably 1 or more days at room temperature. 

Working with yeast, I would just use a lot less yeast.  For instance, the Jim Lahey (NYT) No Knead bread calls for just 1/4 tsp of yeast vs something like 1 to 2 tsp for a typical one loaf recipe.  I have no idea if you can cut a starter back as sharply, but I hope some of the sourdough folks can tell us.  You might need a higher hydration as well with so little leavening.

I'm glad you tried the experiment. 

firepit's picture


After taking a break to focus almost exclusively on school, I'm finally back in the kitchen again. As I feared, neither Leon nor Leon surived my lenghty trek into deepest academia, so they had to be let go. I'm not sure what happens to yeast when it dies, but I like to think that they travel to a land flowing with milk, flour and honey. Anyway...I had a very easy time getting my new starters, Leon (white) and Doug (Rye) up and going and after about a week, I was ready to bake once more.

After such a long time away, I knew I couldn't just start back in where I'd left off -- you can get hurt trying to do too much to fast, you know -- so I started slowly with a single small sourdough loaf straight from TBBA. I went from my 100% hydration starter to Reinhart's "firm starter" and eventually to the fridge for about 24 hours. Then I built up the dough, adding a bit more water than called for, let it ferment, shaped it and then plopped it into a banneton (thanks SFBI!) and moved it to the fridge. I wanted to explore the "acid takes time, so slow things down" idea, so I left it in the fridge for 24 hours, pulled it out and slowly brought the dough to room temperature over about 6 hours or so. Finally I baked it up. I didn't get the oven-spring I was hoping for, but it was still an agonizing wait to cut into the bread...While it was denser than I'd hoped, it had a distinct tang to it that had been missing from my previous efforts. Success?

Hard to tell. The sour could be a result of slow fermentation or it could be that the new Leon simply had a more acerbic temperament than his predecessors. Schoolwork beckoned, so I had to wait until this weekend to find out. Same starter, same recipe, but I made two identical two-pound batches of dough. Also, in an attempt to lighten up the bread a bit, I added a fair amount of extra water to the dough, and turned it 3 times at 30 minute intervals (a la Thom Lenord's Country French Boule) in an effort to promote a better structure, then left it alone for the last couple of hours.

At that point I took one proto-loaf, shaped it, put it into a banneton and left it on the counter to proof. I took the other, shaped it, put it into a banneton and sent it to the fridge. The first loaf baked up a few hours later and it was tasty with a much improved crumb, but no detectable sour.

Today, about 18 hours later I pulled the second loaf from the fridge and parked it in my proofing box for about 5 hours before baking. Same crumb, but this time, a noticeable, but far from overpowering sour note. Success! It would appear that time is the key ingredient in making a more sour sourdough.

I suspect I'll keep pushing this recipe around for a bit, perhaps adding another day in the fridge, and also trying Bill's suggestion of punching down the levain and giving it more time at room temperature. If that does the trick I may be able to make this a two-day process instead of three, which would be nice.