Inside the World's Only Sourdough Library

Inside the World's Only Sourdough Library

8 Jan 2020


Most people associate libraries with books, but Puratos has taken it a few steps further - something less expected - sourdough.

We are passionate about sourdough and nothing demonstrates our commitment to bread making more than the Puratos Sourdough Library. The first of its kind in the world, you can find the Sourdough Library within the Center for Bread Flavour, in St. Vith, Belgium. The Library aims to safeguard the sourdough biodiversity and preserve the sourdough heritage and baking knowledge. It is here that you will find over 140 sourdoughs collected from around the world. The idea is simple, but important for protecting and celebrating the history of sourdough. Our dedicated Sourdough Librarian, Karl De Smedt travels the world meeting bakers and collecting their unique sourdoughs - one made with chickpeas, another made with beer as an example.

To be on the shelves of the Puratos sourdough library, each inductee is asked to provide the ingredients needed to keep the cultures alive and must provide local flour and additional specific ingredients from their region in order to feed the starter. The sourdough library stores fresh sourdough samples in glass jars at 4°C and refreshes them at regular intervals, according to the protocols established by the source bakery - imagine refreshing over 140 sourdoughs, each with their own unique ingredients and process. This is a process that takes a team of people a week to complete.

The sourdoughs serve another important purpose - they allow us to study the unique science behind sourdough and the threads that tie them together across oceans and time. Additional samples are kept in other locations, these samples are kept as backups and used for research and analysis with partner universities.

Safe in the library, the sample can then be kept alive and maintained for years to come. The sourdoughs that reside in the library have contributed to the identification of more than 700 types of yeast and more than 1500 varieties of lactic acid bacteria. Proudly represented in the library are two sourdoughs from Canada - Black Bird Bakery in Toronto, Ontario and a sourdough dating back to the Klondike Goldrush in the 1890's from Whitehorse, in the Yukon Territories.

The library is a non-profit initiative. It is Puratos' way of contributing to the wonderful world of natural ferments and the technology of fermentation while guaranteeing bakers the safeguard of their sourdough. It also helps us to become better at our job, thanks to the study of their composition.

To take a virtual tour of the sourdough library, click here. If you have your own sourdough, or want to learn more about Sourdoughs from around the world - check out

This article has been written by Danielle Aucoin, Product Manager - Bakery, Puratos Canada, in collaboration with our Sourdough team from Puratos Headquarters in Belgium. Danielle has 10 years of experience in the Canadian bakery industry - in both retail and foodservice markets and shares a passion for innovation and baked goods.