In October 2019 Kaslo Sourdough initiated a new research project with Dr. Michael Gänzle, an expert in sourdough fermentation research at the University of Alberta, where he is Canada Research Chair in the Agriculture, Food and Nutritional Science Department. Dr. Gänzle is one of the leading experts on lactic acid bacteria in the world. The research project aimed to characterize the individual bacterial species that comprise the Kaslo Sourdough culture, in order to verify that the culture is unique. Kaslo Sourdough is now pleased to share the results of this research.
Through the study, Dr. Gänzle’s lab received samples of the Kaslo Sourdough culture and fermented pasta at three different intervals of the fermentation cycle, including one sample that was hand-delivered by Silvio Lettrari, the owner-operator of Kaslo Sourdough.
“I had to fly from the Kootenays to Edmonton in January just to make sure that the culture got there within the appropriate time frame. If we had the sample couriered, even in a cooler, it would have taken too long given the holidays,” Lettrari said. He explained further: “With sourdough, it’s a living culture. So the temperature the culture is stored at is really important. The bacteria continue to multiply, and we needed to get them to the lab at a certain stage in the fermentation process.”
Taking samples and analyzing them across different stages of the fermentation process is necessary to confirm that the sourdough culture is stable – in other words, that the species of lactic acid bacteria are consistent across different batches of product and at different stages of fermentation. In the case of Kaslo Sourdough’s fermented pasta, the study confirmed that the culture is stable and samples taken over a period of several month showed a very comparable composition of fermentation micro-organisms.
“We were happy to have confirmation that the culture is stable. That was already one piece of good news,” said Lettrari. “With research, you never know what you’re going to get! So to have our culture confirmed was a really good start.”
Further, the research shows that Kaslo Sourdough has a unique composition of sourdough culture. It’s common for sourdough cultures to have several dominant lactic acid bacteria types – that helps to determine whether it is a distinct culture. For example, the iconic San Francisco sourdough bread in the Bay Area in California is fermented with a combination of Fructilactobascillus sanfranciscensis and the yeast Kazachstania humilis. The dominant lactic acid bacteria in that bread was named to reflect its “birthplace” but these two organisms are also found in other sourdoughs worldwide including Italian Panettone, German Pumpernickel, and Chinese steamed bread. In contrast, Kaslo Sourdough’s culture has four unique species of lactic acid bacteria.
“We currently recognize over 250 different species of lactobacilli,” explains Dr. Gänzle, “and the species-level composition of micro-organisms of over 500 different sourdoughs has been described in the scientific literature. The species composition that we found in Kaslo Sourdough’s fermented pasta is unique and Kaslo Sourdough has an exceptional sourdough culture, reflecting the unique fermentation conditions.”
Kaslo Sourdough’s culture is also very low in yeast, another common organism in sourdough cultures. Typical sourdough cultures usually have yeast cell counts between 1-10% of the total microorganisms counted in the culture, but the Kaslo Sourdough culture had less than 0.01%, which is exceptionally low.
“We’re very happy with the results,” says Kaslo Sourdough Production Manager Stefan Lettrari. “We have a unique product, a unique way of undertaking our fermentation process, and it results in a one-of-a-kind fermented pasta. It’s good to confirm that what we’re doing is different from anything else out there right now.”
Another interesting characteristic of the sourdough fermentation emerged from the study. While the lactate concentrations, a by-product of the lactic acid fermentation, were very similar to those typically found in other sourdoughs, however, the concentrations of acetic acid, another common by-product, were 5-10 times higher than those usually expected in sourdough fermentation. This could be something that contributes to the flavour profile of the pastas. Additionally, the presence of high lactate which can be converted to other compounds during fermentation has been used in experimental sourdoughs to extend the mould free shelf life of bread, but it is a first to see it here in an industrial sourdough culture for fermented pasta.
Kaslo Sourdough thanks Dr. Gänzle and his post-doctoral scientist, Justina Zhang, for their work on this research.
Next Steps. Kaslo Sourdough and Dr. Gänzle are still in discussion about next steps. Having established the unique and distinct composition of the sourdough culture, one option is for Kaslo Sourdough to join as an industry partner a broader research study to investigate with Dr. Gänzle how the unique fermentation micro-organisms relate to the flavour and nutritional quality of pasta.
About Kaslo Sourdough. Kaslo Sourdough is Kootenay-based, award-winning company known for their high quality products, innovation and leadership contributions to the grocery food industry in Western Canada. They have been producing sourdough pastas since February 2012, and sourdough breads since the early 1990s. Most recently, in 2017 they won Product of the Year at the Vegan Expo with their hemp sourdough pasta.
Funding for this project has been provided by the Governments of Canada and British Columbia through the Canadian Agricultural Partnership, a federal-provincial territorial initiative. The program is delivered by the Investment Agriculture Foundation of BC.Back to news