Sourdough recipes, especially bread, have become a popular trend in recent years.

In order to bake sourdough recipes, you must first prepare a sourdough starter. 

Sourdough starter, often referred to as the "mother dough," is used to make dough rise instead of using the active ingredient yeast. 

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For those well into their home or business endeavors as sourdough bakers, the length of time in which an individual has kept a single sourdough starter alive is something to brag about. 

And for some, sourdough starters have even become somewhat of an heirloom, being passed down through generations.

Sourdough starter in jars

Sourdough starters are created by mixing flour and water. (Natasha Breen/REDA&CO/Universal Images Group via Getty Images)

These old sourdough starters have been used by generations of bakers. 

Oldest sourdough starter in history

In 2020, Seamus Blackley, the creator of Xbox and a seasoned baker himself, baked sourdough bread from dormant yeast samples that are 4,500 years old, according to the Atlas Obscura website. 

Remnants of yeast samples from ancient Egyptian baking tools were removed and brought back to life by the video game designer and others, including a biologist and an archaeologist.

The trio scraped the yeast from ancient Egyptian pottery, decoded hieroglyphics to practice ancient baking techniques and baked the bread in clay pots. 

The result? It worked and Blackley hopes to recreate the technique to sell to consumers.

Boudin Bakery: San Francisco

Boudin Bakery in San Francisco has been using the same sourdough starter since 1849. 

Boudin is the oldest continuously operating business in San Francisco, its website says. 

This bakery was also the first to invent sourdough french bread, according to the same site.

Sliced sourdough loaf

Many bakeries use very old sourdough starters in their recipes. (Rene Johnston/Toronto Star via Getty Images)

"The sourdough baking process has existed for thousands of years, but Boudin Bakery was the first to combine the sourdough process with French baking techniques to create the first sourdough French bread in 1849," reads the Boudin site.

While you can easily find an assortment of unique sourdough starter recipes online, you won't be able to find the one used at Boudin Bakery. 

The establishment holds its starter very near and dear.

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On its website, the group advises that each loaf of sourdough bread is made with a "portion of the original mother dough that dates back to the first loaf."

Chrissi's Farmhouse Bakery: Gardnerville

Bakers at Chrissi's Farmhouse Bakery in Gardnerville, Nevada, make their bread from a few different starters, all of which are quite old. 

The bakery's website says it has three sourdough starters that are used regularly.

"This starter is a mix of three of my historic starters that I acquired and a true San Francisco starter that is 233 years old. Two of the historic starters are from the California foothills and a 100-year-old from Montana. This is our every day tried and true Pioneer starter," the website states of the Gardnerville Born starter.

Then, there's the Saint Honoratus Wheat starter, which dates back 900 years. 

This impressively old starter originated from Wales, according to the site. 

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Lastly, this bakery houses the East Valley Rye starter. 

"This starter began as a Mother from a 100-year-old Montana starter. We mixed in a Bavarian starter that is said dates back to 1633 in the town of Oberammergau," the website states. 

Hobbs House Bakery: San Francisco

With multiple locations in the United Kingdom, Hobbs House Bakery has been taking care of its sourdough starter for 68 years — and it's still going strong. 

Dough being made in a bowl

Sourdough starter is added to a recipe to make the dough rise. (Laura Chase de Formigny for The Washington Post via Getty Images)

Since sourdough starters do take a certain level of care, having to add more flour and water to the batch each day, it's not uncommon for bakers to give their starters a name. 

Hobbs House Bakery appreciates its sourdough starter so much that in 2020, it threw it a birthday party.

The bakery shared an Instagram post in celebration of the starter's 65th birthday. 

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"Our Sourdough Starter has turned an impressive 65 years old!" the bakery wrote on Instagram.

"Unlike most, she will not be retiring at this age — she will be working for many more decades to come, rising an infinite amount of magnificent loaves." 

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