A loaf of salt-rising bread. (Photo: Wonderland Kitchen/flickr)

Its flavor is often described as ‘cheese-like’, its crumb dense, and its odor memorable. Salt-rising bread is special to those who remember it as a home-cooked comfort by a grandmother or parent. It’s also one of the only breads that uses a mix of bacteria, rather than yeast, to rise–a mix that includes a form of Clostridium perfringens, the culprit commonly known to cause the discomforts of food poisoning and the purulent wounds of gangrene.

No one exactly knows where salt-rising bread originated, but the prevailing idea is that pioneer women developed the bread as they traveled along the Appalachian mountain range, where the bread is most often found today. Before the 1860s, commercial yeast didn’t exist–most breads were leavened through sourdough starters, or by skimming the yeast and bacterial byproducts from the beer making process, neither of which were available in pioneer life. Salt-rising bread doesn’t need yeast to rise, and contrary to its name, the bread doesn’t really need salt; the use of heated rock salt to regulate the temperature of the starter dough for pioneers very possibly contributed to its name.

Salt-rising bread’s pungent, sharp smell is either loved or hated, and sometimes compared to dirty socks, with a unique cheesy taste that aficionados love. After its invention the bread became incredibly popular, with recipes for it appearing in many cookbooks into the 1920s; it even played a central role in the Kansas governor’s race in 1910. Even in 2012, Country magazine called salt-rising bread its “all-time most requested recipe.”

Glenda Riley writes in The Annals of Iowa journal that the meals of one pioneer “regularly featured … salt-rising bread, which she worked at in between her other chores,” starting the bread as they made afternoon camp, letting it rise until midnight by the fire, and having the dough rise again until it was ready to bake at breakfast time, ever with a watchful eye that the dough was rising properly.

A family outside their cabin in the Appalachian Mountains, where salt-rising bread is said to have originated. (Photo: Library of Congress)

If you think this sounds time-consuming and difficult, you would be correct. In Beard on Bread James Beard agrees that salt-rising bread is “unpredictable,” adding that, ”You may try the same recipe three or four times and find that it works the fifth time…you may be disappointed.” If you Google salt-rising bread, one of the first results is an allrecipes.com entry that warns in the shouting tone of capslock: “THIS IS NOT AN EASY BREAD TO MAKE!”

In the early 20th century, this lengthy, yeast-less process also became an interest of microbiologists. In 1914, Richard N. Hart noted in his book Leavening Agents that salt-rising bread “seems to fail in a well-sterilized room,” and alludes to the experiments of Henry A. Kohman, who discovered that salt-rising dough lacked yeast completely “but literally swarmed with bacteria.”

In 1910 Kohman was funded by the aforementioned bread-obsessed Kansas Governor, Walter R. Stubbs, to learn how bakers may reliably make it, and concluded that a variety of anaerobic bacteria allowed the bread to rise. In 1923, microbiologist Stuart A. Koser began to suspect the mix might include bacteria found in human intestines and wounds.

More Clostridium perfringens bacteria, an essential element to salt-rising bread. (Photo: Public Domain/WikiCommons)

To explore his hypothesis, Koser started with a few experiments that exposed guinea pigs to the bacteria, and confirmed that innocuous Bacillus welchii (now called C. perfringens) spores were present in the bread, but his experiments quickly dove into the macabre. He decided to take it a step further and bake a loaf of his own using the toxic bacteria from a soldier’s gangrenous wound.

Koser made a salt-rising bread starter in his lab, and successfully created the grossest, and possibly the most dangerous bread in history–the wound-bacteria made bread that did not go over so well with the guinea pigs this time around.

It seems that practically anything can capture the right bacteria to make salt-rising bread. A man named Reinald Neilsen conducted dozens of baking experiments using different salt-rising bread starters. In 2002, he published an article in Petits Propos Culinaires on how he successfully made salt-rising bread starters out of oats, cheese, and even tree bark–which apparently works well, but needs to be picked out of the bread as it’s eaten.

The diverse range of salt-rising bread starters is possible because of the bacteria they attract. Salt-rising bread bakers create a fruitful environment for bacteria using a process called alkaline fermentation. Boiling water or milk is poured over a base like cornmeal or potatoes. It is left to sit for hours between 90 and 110 degrees Fahrenheit before flour is added and it sits again. This captures a medley of wild bacteria including Bacillus, C. perfringens and Lactobacillus, which feed from each other in a symbiotic relationship visible in the bubbling, foaming mixture that forms, called the ‘sponge’. After nine to 12 hours of bacterial growth, it’s ready to bake.

Typically, this sounds like the opposite of what one wants to do with food. The dangerous strains of the C. perfringens bacteria are what keep us from eating old meat, the nightmare that keeps restaurants in a constant state of concern about food temperatures, and the microbe responsible for gas gangrene necrotic enteritis. So how have generations of Appalachian cooks been eating this bread, which hasn’t produced a single case of food poisoning?

The truth is, the strain of bacteria in salt-rising bread is completely safe–though the reasons why are slightly mysterious. Jenny Bardwell and Susan Brown, professional bakers who have researched how salt-rising bread works for over 20 years, collaborated with microbiologists test it. The resulting paper, “The Microbiology of Salt Rising Bread,” published in West Virginia Medical Journal, notes that the bread does contain this bacteria, but testing indicates the strain is “unable to cause C. perfringens type A food poisoning.”

Clostridium perfringens colonies. (Photo: Public Domain/WikiCommons)

The reason this strain exists may lie in bacteria’s ability to change. In certain environments, bacteria may find a mini-evolutionary advantage to gaining or losing genetic traits–including traits that involve giving off toxins. The environment of a wound, in contrast to that of bread dough, might attract and cultivate very different strains of the same bacteria. Even if toxic strains of C. perfringens make it into the bread, study co-author Gregory Juckett notes that baking temperatures are far above tolerance levels for the bacteria.

Since salt-rising bread has so far been known as a niche food item, there has been little funding to study it, but there have been studies with other breads using bacterial fermentation. In Greece a similar bread uses chickpeas, and in Sudan another calls for lentils. Preparations of both items indicate that the result is like that of salt-rising bread. Kenkey, a dumpling-like bread from Ghana made of a corn-based fermented dough, may also use a related process.

Not everyone has the drive to experiment, however, and the time needed to make salt-rising bread is what eventually caused it to recede into obscurity. By 1920, the book Manual of Homemaking had labeled salt-rising bread, “An old-fashioned bread, the making of which is almost a lost art to-day.”

Susan Brown with her grandmother, who routinely baked salt-rising bread. (Photo: Susan Brown/saltrisingbread.net)

Bardwell and Brown explain in The Handbook of Indigenous Alkalyne Fermentation that by the mid-1900s salt-rising bread was available in bakeries, with fewer people baking it at home. When production of commercial salt-rising bread starters ceased in the 1960s, most people stopped making it. Today salt-rising bread is usually sought because of nostalgia, the memory of lost family members and home-cooked meals; Bardwell and Brown’s own personal ties to the bread go back generations, and are part of what inspired their research in the first place.

“There are memories that tastes provoke and smells provoke–and salt-rising bread has a very strong smell,” says Brown. “People will come into the bakery, take a loaf, put it up to their face and take a really long, deep breath.” At Rising Creek Bakery in Mt. Morris, Pennsylvania, Bardwell and Brown bake salt-rising bread and hope to revive the tradition, teach anyone who will listen how to make it, and encourage scientists to study it. Bardwell and Brown believe that salt-rising bread may even further teach microbiologists how probiotics keep us healthy.

“Susan and I have many responses from people saying that salt-rising bread calms their stomachs and is soothing to them when they can’t eat anything else,” says Bardwell. “Salt-rising bread may even be some kind of cure that helps people.” This might make sense– C. perfringens and Lactobacillus are, after all, both present in the human digestive system. Amid studies about intestinal flora and a constant stream of probiotics on grocery shelves, studying and eating this unlikely food may hold more benefits than its pioneer inventors knew.

In honor of Thanksgiving, here is Susan Brown’s recipe for salt-­rising bread stuffing:

Salt Rising Bread Stuffing

Ingredients:

16 cups of 1 inch salt rising bread cubes (1 1/2 # loaf)

8 tablespoons (1 stick) unsalted butter

2 cups medium diced onion (2 onions)

1 cup medium diced celery (2 stalks)

2 tablespoons chopped, fresh parsley or 2 teaspoons dried parsley

1 tablespoon salt

1 teaspoon black pepper

1­2 cups turkey broth or chicken stock

Preparation:

1. Preheat oven to 350 degrees Fahrenheit.

2. Place the bread cubes in a single layer on a sheet pan and bake for 7 minutes.

3. Remove the bread cubes to a very large bowl.

4. Melt the butter and add the onions, celery, parsley, salt, and pepper. Cook over medium heat for 10 minutes until the vegetables are softened. Add to the bread cubes.

5. Add the turkey (or chicken) broth or stock to the mixture. Mix well and pour into a greased 9-by-12-­inch baking dish.

6. Bake, uncovered, for 30 minutes, until browned on top and hot in the middle. Serve warm.

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