We’ve found a few errors in Bread Science. These are listed below. We’ve corrected most of them in the second printing, and  and will make a few more in the third printing; look for the words “Second printing 2009″ or (Third printing 2017” on the copyright page of your book to tell which version you have. I’ve also mentioned some topics below that needed further consideration; these have not been altered in the second and third printings.

On page 139 (first printing only). The two pictures are backwards, i.e., the under-kneaded dough is the one with holes in it, and the well-kneaded dough is the one that is smooth and not ripping. Thanks to Bruno Sorrentino for his vigilant reading!

There are also switched pictures on the very bottom of page 163 (first printing only). The hand using the friction of the table to tighten the dough is on the left, while the hands tightening the dough are on the right. Thanks to Dave Glaze for pointing this out.

On page 111 (first printing only), the temperature of 25 degrees Celsius is converted to 40 degrees Fahrenheit. This temperature should actually be 40 degrees Fahrenheit or about 4.5 degrees Celsius—a cold temperature. (Thanks to alert reader Stan Matthews who pointed out that the cooler temperature is correct!)

On page 114, I state that a starter’s flavor reaches a stable point after about 9 months. A reader pointed out that this occurs with a daily feeding schedule. If you are feeding your starter weekly (as most home bakers do), it may take longer—his took 18 to 24 months. (My apologies, I can’t remember who told me this.)

On page 204 (first printing only), there is a mysterious question mark at the end of the first paragraph (? cup). This should read “7/8 cup.”

On page 212 (first printing only), there is a missing space in the recipe—the amount of whole wheat flour is 1 2/3 cups (i.e., one and two-thirds cups), not 12/3 (twelve-thirds) cups.

On page 235 (first and second printings only), I give the conversion factor for water as 1 cup = 0.224 kg. I don’t know what I was thinking! (Somehow I used 28 grams per fluid ounce—maybe I used the “imperial ml” instead of the U.S. mL?) There are 29.57 U.S. mL in 1 fluid ounce, and the density of water is 1 gram per mL, making the correct conversion factor 1 cup = 8 fluid ounces = 0.237 kg. (Thanks to alert reader Jim Hicken for pointing this out!)

This results in a slight decrease in the water *volumes* given in the recipes (all printings), but remember that the volume measures are all slightly approximated anyway, as they are rounded to the nearest quarter cup, and you should be feeling your dough to achieve the right consistency (soft and flexible without being sticky, unless you’re making a wet dough like ciabatta).

On page 21 (first and second printings), I describe active dry yeast as “almost totally dried” and instant yeast as “partly dried.” I guess this seemed like a logical assumption, but I heard a talk on yeast by Dominique Homo from LeSaffre who said that instant yeast is actually drier than active dry; it is a difference in the drying process that protects the yeast cells from dying in instant yeast (the instant yeast is “rapidly dried”). Also, while on the subject of yeast… since writing Bread Science, I’ve become less hesitant to tell students that they don’t need to activate active dry yeast. However, I’ve also realized that I ALWAYS use an autolease when I make bread, and it might be that the yeast becomes activated during this rest period, and that’s why I’ve never had a problem. For the complete notes from Dominique’s talk, see the post on my blog:

Alert reader Spencer Leong pointed out to me that stronger and softer doughs require different treatments during shaping. I describe degassing dough during shaping by smacking it to get all the gas out. With a softer French dough, you would not want to flatten the dough totally—you want some gas left in there, contributing to the final holey internal structure. The odd thing is, my original manual (written as a class manual), which turned into this whole book endeavor, actually had a page about this–how to treat a softer dough when shaping. I thought I had included it in the book, but somewhere along the way it must have disappeared! Thanks, Spencer!

On page 108 (all printings), I describe making preferments in a plastic container, to avoid using metal. Since writing the book, I’ve become less trusting of plastic, given the continual discovery of new potentially toxic chemicals in some plastics. I still make poolishes in BPA-free Rubbermaid containers, but I keep my sourdough starter in a glass bowl.

Sourdough enthusiast Mike Avery sent me a lot of interesting information about sourdough starters. He told me about experiments with irradiated flour (in which all the microorganisms were killed) and starters made with boiling water (which would also kill off microorganisms in the flour). These mixtures had a lot of trouble becoming sourdough starters. This implies that it is the microorganisms in the flour, more than the air, that result in a sourdough culture. Mike suggested that starters may change flavor when a different flour is used for feeding, and that this might often happen when the starter changes location. (It’s not the location change that causes the flavor change!) So if you want to have the same sour flavor as your favorite San Francisco bakery, you need to buy the same flour they use!

Mike also mentioned that he finds his starters revive faster if they are refrigerated soon after feeding, not left out for several hours. This is in line with research by Dr. Sugihara, who studied the survival rate of microorganisms in frozen starters. (I do suspect, though, that Mike takes excellent care of his starters. I was a bit of a slacker with mine, and always felt like I had to make sure they were alive [i.e., rising] before I refrigerated them.)

I’ve become concerned about cracking pizza stones, casseroles, and even oven windows, and urge everyone to be careful when baking! Here are some things I’ve discovered:

  • Cold water dripping on a pre-heated oven window can crack it! Be careful when you place a dripping loaf of dough into the oven, or when your nervous hand reaches over the oven door to pour water (for steam) onto a hot frying pan. Some people quickly place a towel over the oven window and then whisk it away before closing the door.
  • Pizza stones can also crack. The instructions say to preheat it with the oven, not put it in cold. This is to avoid the extreme temperature changes that crack it. But putting cold dough on the hot stone can also crack it. I used mine regularly, with no problems, and then it cracked during a class when it had been in the oven all day. Perhaps it got hotter than usual? It was a thin pizza stone. (Mom got it from the Pampered Chef.) If you want to do heavy duty baking, I’d recommend seeking out a heavy duty stone. Another suggestion (from a reader) is to use kiln shelves. You can get them from online pottery suppliers, and they “come in all sizes, shapes, thicknesses, and strengths. The higher fire varieties are harder to break, i.e. more resistant to shock, but more expensive.”
  • Baking in a casserole is an alternative to baking in a cloche; but knowing that temperature changes can crack materials makes me fear for the casseroles of the world. Avoid using anything special; I’d look for cheap ones at the thrift store to experiment with. I’ve recently gotten an old Corningware casserole (which supposedly can take temperature changes), and it has been great—cold dough on a preheated casserole has not cracked it.
  • I have not yet found a Dutch oven to use; this is another oven-safe way to bake.

A word about convection ovens: I long thought that convection ovens were bad for steam, because their fans dry out the air inside. Then I had the opportunity to bake in a house with a convection oven, and the bread had a lovely brown crust! The owner said he thought the fans recirculated the oven air without replacing it (sort of like the settings on car air-conditioners, I guess, for recirculated air vs. outside air). This makes sense—why would the oven fan suck out the air (and heat)? But then, at another house, the “TRU Convection” setting produced terrible crust and the brownness and shine improved when we turned it off! So the jury is still out on convection ovens; different brands might function in different ways. Try baking with and without and see which is better!

Doc Dougherty alerted me to this paper that examines tyrosine cross-links in gluten as an alternative to the usually accepted disulfide bonds. Basically, they make some dough and then run it through machines to analyze its amino acids, and they see that tyrosine cross-links are present. It seems likely to me that both types of bonds, tyrosine cross-links and disulfide bonds, could be at work!

Deb Bartlett wrote with some info about freezing or drying sourdough starter. On page 128, I describe a successful short-term experiment, but wonder about freezing sourdough long term. Deb writes, “… the miners of the Klondyke gold rush kept some starter in a bag somewhere on their bodies through the long, cold winters. It might be around their necks, under their hats or inside the long underwear—anyplace that kept it warm.

“That is because one thing that will kill a sourdough starter is freezing…. One very effective way to keep starter over the long term is to dry it: simply spread some starter over parchment paper, as thin as possible (you might need to water it down a bit) and let it dry, either on the countertop or in a very low oven or a dehydrator. When it is completely dry, break it into little pieces and store it in an airtight container in a dry place, preferably out of the light.

“When you want to get a starter going again, take about 1/2 to 3/4 of a cup of ‘chips’ and pour about 1 1/2 cups of warm water over them. Soak and stir until they dissolve. You might need to add more warm water. Once that has happened, let it sit for a few hours, then feed as usual and leave out. It might need a bit longer to get to where you want it and maybe a refeeding, but soon your starter will be alive and bubbling. You can keep a starter for a long time in the dried form, providing it stays dry in storage so that it doesn’t go moldy.”

I’ve read other accounts of successfully storing starter with this drying method, including some trials that lasted several years. I’ve also read of starter surviving a year of being frozen.