The Fresh Loaf

News & Information for Amateur Bakers and Artisan Bread Enthusiasts

Consistent Crackly Crust Conundrum Conquered?

dmsnyder's picture
dmsnyder

Consistent Crackly Crust Conundrum Conquered?


Achieving a thin, crackled crust has been a frustrating pursuit for many, myself included. I have been able to get it, sometimes, but not consistently. There have been numerous discussions of how to get that crackly crust. I've been slowly digesting what's been written, and I think I may have arrived at a reliable method, at least for my breads, my dough handling and my oven.


The basic principles


The crust crackles during cooling because the interior of the bread contracts as it cools, and the crust is too dry to absorb water vapor which is trying to migrate outward and too rigid to contract with the crumb.


In order to optimize oven spring, bloom, crust shine and crust thickness when baking hearth breads, it is necessary to have a moist environment for the first part of the bake. Keeping the surface of the bread moist delays hardening of the crust, so it is extensible enough to expand with oven spring and permit a nice blooming of the scoring cuts.


Thus, it is desirable to have a humid oven for the first part of the bake but a dry oven for the last part of the bake.


Convection ovens, by increasing hot air circulation, tend to dry the surface of whatever is cooking. That's nice for crisping chicken skin, but it is counter-productive for keeping the bread surface moist early in the bake. On the other hand, convection baking helps dry the loaf surface, as is desirable during the last part of the bake. Convection ovens made for bakeries solve this problem by injecting steam under pressure over a time period under control by the baker. The home baker can achieve something like this by covering the loaves or using a cloche for the first part of the bake. The cover protects the loaf from excessive water evaporation, even in a convection oven. When the cover is removed, the crust can be dried, and a convection oven can presumably achieve this better than a conventional oven.


Allowing the loaf to sit on the baking stone with the oven turned off and the door ajar can achieve additional crust drying, but it may be that a less gradual cooling results in faster contraction of the cooling crumb and greater likelihood of crust crackling, according to some.


The protein content of the flour used and the inclusion of other ingredients that increase water retention, for example, potatoes or soakers, may also have an impact. These factors may impact both the degree to which the crumb contracts and the difficulty of drying the crust, and both of these would inhibit crackle development. If so, crackles should be easiest to achieve in a straight bread dough made with lower protein flour. Indeed, the bread most associated with a thin, crackly crust is baguette, which meets these conditions.


The principles applied


My oven is made by KitchenAid and has both convection and conventional baking options. This provides me with the opportunity to apply the principles discussed above.


I baked two breads yesterday and today with these principles in mind. The first was one I've baked dozens of times, my San Joaquin Sourdough. The second was one I had not baked before, the Vermont Sourdough with Increased Whole Grain from Hamelman's Bread. Both breads had 20% pre-fermented flour in the form of a 125% hydration starter fed with a mix of 70% AP, 20% WW and 10% whole rye flour.


The San Joaquin Sourdough was made with KAF AP and 10% KAF Medium Rye flours. The dough was 72% hydration. The loaves were scaled to 480 gms and shaped as bâtards. The Vermont Sourdough with Increased Whole Grain was made with KAF Bread Flour and 15% KAF Medium Rye Flour. The dough was 65% hydration. The loaves were scaled to 810 gms and shaped as boules.


For both bakes, the oven was pre-heated to 500ºF on convection bake for 60 minutes, with a baking stone on the middle shelf, pushed to the left, and a 7 inch cast iron skillet filled with lava rocks at the right front of the lower shelf. The oven was pre-steamed by pouring about 1/3 cup of boiling water over the lava rocks. The loaves were then transferred to a peel, scored and loaded onto the stone. Another ½ cup of water was poured over the lava rocks and the oven door quickly closed. The oven was immediately turned down to 460ºF, conventional bake.



San Joaquin Sourdough Bâtards



Vermont Sourdough with Increased Whole Grain from Hamelman's "Bread"


For the San Joaquin sourdough, the skillet was removed from the oven after 12 minutes, and the temperature was reset to 440ºF, convection bake. After another 18 minutes, the oven was turned off, and the loaves were left on the stone with the oven door ajar for another 7 minutes before being transferred to a cooling rack. The loaves commenced “singing” immediately and exceptionally loudly. By time they were cooled, they had developed many crust crackles, as pictured.





Crackly Crust on San Joaquin Sourdough


For the Vermont Sourdough with Increased Whole Grain, the skillet was removed after 15 minutes, and the oven was re-set to 435ºF, convection bake. The loaves were baked for an additional 25 minutes. Then, the oven was turned off, and the loaves were left on the stone with the oven door ajar for another 7 minutes before being transferred to a cooling rack. The loaves were already singing when I took them out of the oven, and, to my delight, there were already a few crackles. I had never before seen crackles develop before a loaf was cooled out of the oven. More lovely crackles appeared as the loaves cooled.



Crackles in crust of Vermont Sourdough with Increased Whole Grain, right out of the oven



More crackles appeared as the loaves cooled



And more ...



And yet more crackles


Conclusions


While two bakes is not sufficient to completely establish that the method described will reliably produce a crackled crust with all hearth breads, or even these, every time, this experience certainly supports my current understanding of the mechanisms involved and suggests the possibility that other bakes and other bakers might achieve similar results by applying these techniques.


I'd be happy if others would give this a try and share their experience.


David


 


Comments

proth5's picture
proth5

but I'm looking at more "hard time" in Okinawa and my poor old oven is not convection.


A little off the topic, but how do you like that Kitchen Aide oven?  I've decided that I need to get off the dime about replacing my oven and have been giving serious thought to a KA convection oven.  Anything for which you be especially alert or would demand if you were buying one today (I've decided against the steam assist - but am still pondering other models)?


Thanks

dmsnyder's picture
dmsnyder

Hi, Pat.


My oven is the "Superba Select 30" model. It is a 13 year old built-in. It seems to heat to the setting, heat evenly and has worked reliably. The only problem I have ever had with it was the door glass cracked once, which was entirely my fault and happened during my experiments with various oven steaming methods. The oven is self cleaning, and that feature works well too but, strangely, only when you use it which I don't do often enough.


My only wish is that it were wider, so I could bake longer baguettes than the "mini" ones for which I must settle. 


I haven't looked at what's come on the market since we were choosing ovens 13 years ago, so I can't comment on alternative models or makes. The only features I've heard about that sound desirable are a lower temperature setting than 100ºF (my lowest, meant for dehydrating veggies and fruits) which I'd use for proofing dough and a rotisserie. 


David

ehanner's picture
ehanner

My wife and I have been trying to decide what to do with our oven situation too. We have a GE built in wall oven similar to yours David. Ours doesn't have a convection option but I like the wall mount height.


The trouble is if we buy a wider oven, it won't fit in the cabinet. That means new kitchen cabinets and a jump from a few hundred to a few tens of thousands. Who would install new cabinets without upgrading the other appliances. Then the counter top would look so nice in that beautiful granite that goes beautifully with the Italian tile. And so for me, that is how I end up spending a boatload on a simple new oven. But I do need a new oven. Truth is the kitchen could use a remodel after all.


Eric

dmsnyder's picture
dmsnyder

You really need those granite countertops with the Italian tile splashboard. Now, just work it backwards until you get to the new, wider stove. The appliance costs have just become incidental expenses.


David

proth5's picture
proth5

Thanks for you thoughts, David.  In general I've heard about the same about the KA appliances.


And Eric, that's exactly why I've been putting off replacing the range - but I don't think I can put it off much longer.  Fortunately I have no desire for those granite counter tops.  A spiral mixer - that's another story...


Thanks, again.

Mary Clare's picture
Mary Clare

if you don't want it!  I have a 27" wall oven and I have oven envy whenever I see a 30" model with a yawning-wide space inside.  I come home and marvel that I have managed to bake for a family of six these many years.  A real miracle : )  

But we ARE re-doing our kitchen island.  This one will have more storage space for all those containers of various grains that I love to dabble with!

wally's picture
wally

Thanks for sharing these very detailed observations, David.  I've been baking a lot of JH's pain au levain lately - mostly using his mixed levains of rye and white with about 8% whole wheat in the final dough.  I'm achieving crackly crusts on every bake so long as I do a full bake (for me, in my gas oven, that's 460 F initially for about 15 minutes, and then lowering to 440 for another 25 - 30 - this for a 1.5# loaf). 


However, now that it's getting humid here in Virginia, I'm finding it's almost impossible to accomplish this with my baguettes (usually poolish-based) which often develop crackles during the winter months.  Doesn't matter how full a bake I do, the crust won't develop cracks nor hold its crispness over a period of several hours.  However, during winter months, I have much greater success.


Perhaps humidity plays some factor here? But that doesn't explain the crackles I get with my pain au levain (and both it and my baguettes are made with Sir Galahad flour).  Can overall volume of the loaf be a factor? Still a puzzle to me.


Larry

dmsnyder's picture
dmsnyder

Hi, Larry.


Well, no one can disagree about humidity being the enemy of crispness (shirts, chips, bread crust).  It seems a de-humidfying bread box would have been invented by now.


I'm glad I don't have to contend with high humidity, since leaving Boston 35 years ago.


David

belfiore's picture
belfiore

As David knows, I am a "newby" to all of this and have, thanks to all of you, learned much since I found TFL.


Imagine my surprise & delight when I read David's post and looked at his pictures...


    OMG!!! You mean it's a good thing to get crackeled crust??? My husband heard unusual noises from my office came in to investigate only to find me doing the Snoopy dance around my chair!


I thought the reference to crackeled crust meant the surface bubbles and when the crusts cracked like in David's pictures I was doing something wrong. I haven't gotten them consistently so now when it happens I'll have to evaluate what I'm doing differenly than when the loaves don't crack.


Yippee! You guys made my day...Thanks!


Toni


 

dmsnyder's picture
dmsnyder

The crackles are not an end in themselves, as I see it. They indicate the crust will be really crunchy and is likely to stay crunchy longer.


The Vermont SD crust was still crunchy this morning.


David

LindyD's picture
LindyD

Very interesting, David; your methodology is excellent.


Since both loaves had lovely cracks, it doesn't seem that the difference in protein had much effect.  I've obtained cracks on loaves using AP and BF - but have no idea why they occurred.


I recall the topic being discussed a while back; I think at that time it was thought that colder temps may play a part.  I tried that by moving my loaves from the oven into an unheated room.  No effect, except the cooling bread made the room smell great.


I have three loaves retarding tonight (all made with BF), so I'll give your technique a try in the morning. The loaves are of different weights (long story) so the timing isn't going to be as precise as yours.


Your oven must be electric, as you remove your steaming pan.  My oven is gas and there's no water left after 10 minutes.  


I wonder if soaking the lava rocks in water for an hour would humidify my oven during the preheating.

dmsnyder's picture
dmsnyder

Hi, Lindy.


I don't recall ever having a gas oven, so I only know what I've heard ... mostly on TFL.


I do have an electric. I remove the skillet out of habit. It's dry. However, when I open the stove at the end of the bake, I often get a burst of escaping steam. I assume much of it is from evaporation from the loaves, yet it must have been retained in the oven pretty well to be able to give me a face full. I gather this would not occur with a gas oven.


David

Wild-Yeast's picture
Wild-Yeast

David,


I have a hunch that if you go over to your Kitchenaid oven and push and hold the "Baked Goods" button for around 7 or 8 seconds the oven will come up in "Bread Raising" mode.  The lowest temperature set point is 90 dF...


Your assessment of crackling crust agrees fairly well with my experience.  Nice slashing style too!...


+Wild-Yeast

dmsnyder's picture
dmsnyder

My oven goes into that special mode, but at 100ºF.


David

ananda's picture
ananda

Hi David,


Lovely breads, as ever, and some very clear and helpful information on the topic being discussed.


I'd apply the Scottish term "well-fired" to your bread; no doubt that helps to produce a crisper crust, more capable of cracking as you want it to.


It's one of the joys of a commercial bakery listening to 200 of these loaves "singing", freshly unloaded from the oven!


I don't have much experience of a domestic gas oven for bread, either.   My mother has an Aga, which is great for bread, but too hot for cakes...so I've baked cakes in her gas cooker which is there as a stand-by.    I too bake on an electric oven at home, with a fan, which I'm reasonably indifferent to.


Lindy, I find a gas oven is a much less dry form of baking, if you get my drift?   Do you agree with that assessment?   As for steam retention, David, your oven door must have very strong seal for you to retain so much steam in the oven.   What is critical here, is the pressure which results; that is key to why you get such a fabulous bake.


Could you clarify about the open door at the end?   How wide do you open the oven door?   How much heat is lost?   I'm really interested in adopting this, but usually have too much bread to bake to have any gaps in the baking schedule to re-heat the oven


All good wishes


Andy

dmsnyder's picture
dmsnyder

I've heard the dark crust (which I prefer on this sort of bread) as "a bold bake."


Re. my oven: Yes. I think it seals tightly. I see steam coming out the vents sometimes, but never around the door.


I think Peter Reinhart was the one who suggested leaving the bread in the oven with the door ajar for a few minutes after it is fully baked. The door is opened just enough to allow moisture to escape. The purpose is to encourage the crust to dry out.


My oven door has a "stop" at about 2 cm where it will stay. If I want the door open a bit less, I just insert a wooden spoon handle in the opening. 


This step is a minor inconvenience when I have two batches of bread to bake back to back. I can't imagine doing this if I had a whole day's baking to do.


David

ananda's picture
ananda

Hi David,


Thanks for coming back so speedily.   I think my oven door will prop slightly open too.   I'll give it a go soon, but make less bread than I normally do.   It doesn't have the sealing power of yours unfortunately.


I'm sticking with the Scottish term; to me all your baking should be described as "bold".   Bold, in the sense of 1. and 2. below; certainly not 3.


1. Fearless and daring; courageous. 2. Requiring or exhibiting courage and bravery. See Synonyms at brave. 3. Unduly forward and brazen; impudent: a bold, sassy child. 4. Clear and distinct to the eye; conspicuous: a bold handwriting   see: http://www.thefreedictionary.com/bold


All good wishes


Andy 

Wild-Yeast's picture
Wild-Yeast

David,


Good.  Now Press 9 followed by 0 then Start...


+Wild-Yeast

ehanner's picture
ehanner


The protein content of the flour used and the inclusion of other ingredients that increase water retention, for example, potatoes or soakers, may also have an impact. These factors may impact both the degree to which the crumb contracts and the difficulty of drying the crust, and both of these would inhibit crackle development. If so, crackles should be easiest to achieve in a straight bread dough made with lower protein flour. Indeed, the bread most associated with a thin, crackly crust is baguette, which meets these conditions.



David, and others,


While your ability to create the crackles in larger breads is desirable and adds to the overall flavor, I wonder about this applies to the baguette. A thin crispy crust that shatters easily is what I am striving for. One with a golden and "Less Bold" finishing color. I think I am feeling that a heavier steaming for a shorter time will produce this effect, especially if the dough is shaped without additional flour on the surface. Shaping technique is also important here to create a tensioned cloke (Julia's words) in the  gluten that will later caramelize and crisp up.


High humidity is unfortunately the curse of summer weather. Alas, the ability of air to hold moisture doubles approximately with every 10 degrees F of increase in ambient temperature. Unless your home air conditioning unit will dry out the cooled air to 60% even when it isn't working hard, we are stuck with leathery crusts very quickly. Living in the higher elevations would solve this problem also.


So, in conclusion. I think in my next life I want a convection capable oven in the mountains around Chaminoix FR where I'll have access to good flour great wine and spectacular views.


Eric

dmsnyder's picture
dmsnyder

I'm with you in seeking that thin crackly crust on my baguettes. I wasn't going to bake today, but maybe I'll make some straight dough baguettes, just to see if I can do it.


The other bread that I want to have that kind of crust is a light sour rye. That will have to wait, since my rye sour is not refreshed.


David

DonD's picture
DonD

Hi David and Eric,


I agree with David on the steam bake followed by the dry convection bake. I have been using it for a while on baguettes and it works great. You do get the thin, crackly crust. I have 2 ovens, one with and one without convection and I have made side by side comparison and the convection bake at the end consistently provides the crackly crust. I preheat the oven to 490 degrees F, spritz the oven walls w/ water, flip and score the loaves, pour 2/3 cups boiling water on the lava rocks, load the loaves on baking stone, reduce the temperature to 460 degrees, cover the vent holes (my oven is electric), bake for 10 mins, uncover vent holes, remove the cast iron pan with lava rocks, reduce temperature to 430 degrees and bake on convection for 12 mins, take loaves out immediately and cool on wire racks. I think the thermal shock at the end makes the bread sing and develop those sought after cracks.


Don

dmsnyder's picture
dmsnyder

Oooooo ... Now you've got me really excited!


I have a batch of Hamelman's straight dough baguette dough fermenting. The procedure you use is almost precisely what I planned for this bake. I'll amend my usual procedure by skipping the drying in the turned off oven in favor of the "thermal shock" effect. 


Stay tuned!


David

SylviaH's picture
SylviaH

I have it posted on my blog that I had lots of singing and cracks on PR Italian loaf baked in a preheated oven 500F placed the loaf under my steam pan and injected it with steam for 5 seconds, turned down the over to 485 and baked for 30 minutes and removed the lid and baked another 5 to 10 minutes.  Removed the loaf and it sang and cracked...also did the same loaf the day before in the oblong la cloche with a completely different crust appearing..no singing or cracks.


    


Do you think this is this the result of the thermal shock and dry convection air during the last few minutes of baking?


Sylvia

dmsnyder's picture
dmsnyder

Hi, Sylvia.


Anything that dries the crust enough should help get crackles. I'm still processing the thermal shock hypothesis. It's going to be my next tweak.


David

pattycakes's picture
pattycakes

Thanks for passing this along. I have gotten these results, but I never was sure how. I have done your bold bake always and seemed to get the crackly crust with straight 1-2-3 sourdough with a little rye but not with 5-grain levain. This explains it!


Patricia

dmsnyder's picture
dmsnyder

Hi, Patricia.


I think my "principles" are valid, but it's all relative. I'm going to use the baking procedure described for other breads and learn the limits of the techniques. The 5-grain levain would be an excellent test case.


David

dmsnyder's picture
dmsnyder

I just couldn't wait to see if the method described would produce the classic thin crackly crust on baguettes. So, having no poolish or pate fermentée on hand, I made a batch of Hamelman's straight dough baguettes. These take about 5 hours from start to finish.


I followed the steaming procedure I usually do and baked 10 minutes at 460ºF conventional bake with steam then 12 minutes at 430ºF convection bake. I did leave the loaves in the turned off oven with the door ajar for 5 minutes before transferring them to a cooling rack.



I did get some crackles in the crust.




The crust was closer to my ideal than almost any baguettes I've baked before, but it was still not the super thin, shattering crust I want to be able to produce. One barrier to crust perfection was that I baked 4 baguettes at the same time, and they were only 1.5 to 2 inches apart. This almost certainly decreased the drying effect of the convection baking. I also want to test the "thermal shock" hypothesis. So, more tweaking is called for.


I still had some dough left after scaling 4 pieces at 10 oz, so I made some rolls - 2 scaled at 4 oz and 2 at 3 oz.



David

DonD's picture
DonD

Those are some handsome and fierce looking baguettes!


p.s. I agree that the spacing should be far apart enough for the air circulation from the convection to dry out the crust.


Don

dmsnyder's picture
dmsnyder

I appreciate your sharing your baking procedures which prompted me to slightly modify my own, with very happy results. I always feel good when some one else can reproduce my results in their kitchen; I hope you get the same satisfaction.


David

ehanner's picture
ehanner

Now you have me drooling Don. I don't have convection so I'm looking forward to a motivator to swap. I just learned that I have a dual oven available for the asking.


Eric

ananda's picture
ananda

Can't say much more really David.


Yes, spacing of the baguettes, and dough quantity being baked will affect the end quality of the crust.


Best wishes


Andy

dmsnyder's picture
dmsnyder

The ever-present opportunities for additional learning and product improvement sure keeps one excited about bread baking.


David

Marni's picture
Marni

I too get the crackling - but not consistently and didn't realize it was an indicator of anything positive - thanks! 


The real question is can you say Consistent Crackly Crust Conundrum Conquered  three times fast! 


Marni

dmsnyder's picture
dmsnyder

I don't think the crackles themselves are desireable, but the crust that crackles is one that is crisp and likely to stay crisp longer, I think.


I can say Consistent Crackly Crust Conundrum Conquered  three times fast. I think the "real question" was, "Can I bake it three times in a row." Evidently I can, and I bet you can too, if you follow the same procedure.


David

Yumarama's picture
Yumarama

Hi David and everyone,


Jeffrey Hamelman has just posted a corrected correction (!) for this recipe on the MellowBakers.com forum here


This should get the correct amounts to match the sidebar description. I'll be making this bread next weekend so I'll see how it all turns out soon.



Paul,
http://MellowBakers.com
A Hamelman BREAD baking group. Come join us!


dmsnyder's picture
dmsnyder

David