Today, Brown herself bakes the bread. So does her friend, Jenny Bardwell, who owns Rising Creek Bakery in Mt. Morris, Pa. And the two have become experts on this unusual loaf.

Like the neo-butter churners and the cacao bean grinders, Bardwell and Brown are keeping a labor-intensive culinary tradition alive. And they're giving some members of their community who grew up on the bread a nostalgic taste of childhood.

Their research hasn't yielded the definitive origin story. The best guess is that salt rising bread dates to the isolated Appalachian region in the late 1700s, where enterprising women who did not have access to yeast figured out a way to make a yeast-free bread.

The origins of the name are also unclear. One explanation is that pioneer women who crossed the country kept their starter dough warm in the salt barrel, kept atop the wagon wheel.

By day the sun would warm the salt, which would warm the starter. The bread could be made in the evening.

Another possibility: The starter was placed on a bed of rock salt in a box by the hearth.

Either way, the starter takes a long time to ferment.

"Sometimes it's 9 hours, sometimes it's 11 hours," says Bardwell. "You have to be really tuned into this bread. You have to kind of know how to recognize it when it's ready. Not an hour before, not an hour later."

Heat is critical. "Salt rising Bread is primarily wild bacteria you're culturing with heat, about 105 to 115 degrees Fahrenheit," explains Bardwell. She believes the different bacteria interact when heated, raising the bread and giving it flavor and texture.

To find out more about the process, Brown and Bardwell headed to a lab at the University of Pittsburgh to visit pathologist Bruce McClane, who studies Clostridium perfringens — one of the microbes that makes the bread rise.

"We walk in and [the lab] smelled just like salt rising bread!" Bardwell says, referring to the strong smell of the starter, which some people liken to rotten cheese.

The microbe is ubiquitous, they learned — and McClane told them it can be responsible for medical conditions such as gangrene and diarrhea. But the strains in the bread do not usually cause food poisoning, he says. And baking the microbes "significantly" reduces their number, "to the point where they should not be a threat."

The two bakers collaborated with McClane and family medicine professor Greg Juckett on an article for the West Virginia Medical Journal to highlight how SRB has no history of causing any problems.

Meanwhile, the small bakery on the bank of Dunkard Creek is one of the only places in the country that produces the bread, selling it in the shop and shipping out hundreds of loaves each week. Customers surveys reveal that they like to toast the bread and eat it with butter, or drizzle milk and brown sugar on top, or dip it in sweet coffee.

And for many who grew up with salt rising bread, the bakery offers a welcome taste of the past without having to prepare the time-consuming loaf.

Recipe: Salt Rising Bread

There are a half-dozen or so recipes for the pioneer bread on the Internet. This one is featured on Susan Brown's website and comes from Pearl Haines, a Pennsylvania woman who started making the bread when she was about five years old and baked it for nearly 90 years. (Haines passed away this year.) Her starter, or "raisin," as she called it, uses fewer ingredients than most recipes and has no sugar or salt.

Ingredients:

3 teaspoons cornmeal

1 teaspoon flour

1/8 teaspoon baking soda

1/2 cup scalded milk

Preparation:

Pour milk onto dry ingredients in an ungreased quart glass jar or metal, glass, or pottery bowl that holds about four cups. Stir. Cover with saran wrap — and punch a hole in the wrap to keep it from sinking.

Keep starter warm, at 105-115 Fahrenheit, overnight until foamy. Three suggestions: 1) Wrap the bowl in a heating pad at the lowest setting, then wrap a towel around it. 2) Set the bowl in an electric skillet with about half an inch of water, set at the lowest temperature. 3) Put it in an oven if there's a light bulb inside that's about 60 watts and you can keep the bulb turned on, or if the oven has a "proof" setting.

Brown suggests having a thermometer on hand to check the starter's temperature several times during the rise.

After "raisin" has foamed and has a "cheesy" smell, put it in a medium-size bowl. Add 2 cups of warm water, then enough flour (about 1 1/2 cups) to make a thin pancake-like batter. Stir and let rise again until foamy. This usually takes about 1 1/2 to 2 hours. Monitor the temperature during this stage as well.

Next, for each loaf you want to make, add one cup of warm water and 2 to 3 cups of flour (enough to be able to form the dough into a ball). Shape the dough into a loaf and place in a small loaf pan (about 8 1/2 inches by 4 1/2 by 2 1/2) greased with butter, Crisco, Pam or oil.

Let rise 2 to 3 hours. (If it doesn't rise at that point, you'll likely have to start over, Brown says.)

Bake at 350 degrees Fahrenheit for 35 to 40 minutes, or until the loaf is a light golden color and sounds hollow when tapped.

The bread has a long shelf life. "It can keep on your counter for a good week or ten days without going bad," says Brown, "and if you put it in your refrigerator it'll keep for another couple of weeks."

If you encounter any problems, Brown invites you to email her at srbwva@gmail.com.

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