The Puratos Sourdough Library in Belgium is where we physically store many of the most interesting sourdoughs from around the world so as to safeguard them for future generations.

Sourdoughs are living, breathing fermented cultures of flour or other cereals and are therefore by definition fragile, meaning they can always be lost or damaged. So just as the world has found a safe place to keep seeds (for example in the Svalbard global seed vault in Norway), Puratos felt there was a need for a place to keep the sourdough heritage of the world alive and well, too. Not surprisingly many of the leading bakers of the world agree and are happy that someone has volunteered to nurture and take care of a portion of their live sourdough culture elsewhere than in their bakery. After all, their unique sourdough is not just part of the taste heritage of the world but directly linked to their livelihood as well. At last count in July 2018, 108 bakers from 21 different countries in the world had sent a sample of their sourdough culture to be kept in the physical library.

The purpose of the library

While the collection itself is growing, the purpose of the library itself merits more of an explanation. It exists for three main reasons:

1. To preserve the biodiversity of sourdough: All over the world bakers are making sourdoughs. The aim is to collect and preserve certain important sourdoughs coming from a specific region, made from a specific flour or recipe, having a specific story etc. When these sourdoughs arrive, they are stored, analysed and documented for the future.
2. As a backup: A sourdough is the soul of a bakery. By looking after it, and keeping it alive somewhere else than on the bakery premises itself, we are able to provide a sample back to the donors in case their sourdough is lost or damaged; for example, if ever there was an accident at their bakery. A certificate and a symbolic key (to enter the library) is given to every donor so that they can remind their customers just how important the heritage of sourdough is, and how they have a guarantee that the taste they like so much will never be lost.
3. For research: The future library is also evidence of Puratos’ expertise on sourdough and our passion for bread baking in general. Indeed, it has become a key part of the company’s quest to master natural fermentation. Besides that, it has also helped develop a body of research on how to keep these “babies” alive. For the reality is, they need to be fed regularly, and kept in the right conditions, all the time.

A physical library and a virtual one, too

The physical library is currently host to 108 sourdoughs but is capable of housing up to 1000 samples in the future. If, however, you’ve ever wondered how many sourdoughs there are in the world, then it’s worth checking out the Quest for Sourdough website.

We are trying to answer questions one sourdough at a time, and this website lets every sourdough owner on the planet register his or her starter. We’ve already registered 1279 sourdoughs on the website from 1119 cities and 80 different countries around the world. Some are just a few months old, while the oldest is from 1875—that’s 143 years old!

Each sourdough on the website has been specifically identified and you’ll also find some recipes you can try at home: some simple but many much more elaborate. It’s remarkable the variety of starters you’ll find on there… some use different kinds of flour, but there are also some surprising starter cultures for the sourdoughs, like hibiscus and green coffee berries.

There are also a number of films that have been shot on location, like Altamura bread in Italy; Greek sourdough from Amfilochia; Chinese steam buns and a host of sourdoughs from San Francisco.