We sometimes have customers requesting yeast-free breads, and we generally recommend our sourdoughs, which have no baker's yeast added. Technically, sourdough is not yeast-free since it is made with a fermented culture of wild yeasts already present in flours and the air around us.
To find out more about the health benefits of fermented foods, we recommend reading “Wild Fermentation” by Sandor Katz: http://www.wildfermentation.com/wild-fermentation/
Saccharomyces cerevisiae, also known colloquially as baker's yeast (or brewer's yeast for that matter!), is the primary organism used in most bread production today (1), and what we use for our other breads. This yeast takes the sugars present in bread dough and, through fermentation, produces CO2 bubbles which causes bread to rise.
In sourdough, the process is slightly different. The fermentation occurs due to a variety of different wild yeasts and bacterial organisms as opposed to one specific strain of yeast. These usually include strains such as Saccharomyces exiguous, Candida milleri, and Candida humilis (2), various strains of Lactobacillus and Acetobacter, and possibly some baker's yeast as well due to it being airborne in the bakery. An initial culture can be created by mixing flour and water (and waiting usually about 5 days), although adding fruit juices, honey, and/or vinegars can help the process of growth. Once the culture is developed into a viable starter, small portions are taken out to mix into the bread doughs each day.
In order to keep the starter alive, daily 'feedings' of more flour/water mixture are required. At Origin, our culture was started in 2010 and has been grown and propagated since then to produce our sourdough line of breads.
The main characteristics of the tangy taste of sourdough bread comes from the production of lactic acid by Lactobacillus. The lactic acid also contributes to the increased shelf life of sourdough by protecting it from mold growth.
Our white & multigrain sourdoughs are a healthy alternative to your regular bread diet and can add a punch to meals with their wonderful flavours, especially present in our multigrain sourdough. If you are looking for a lovely toaster bread to have for breakfast, consider the multigrain sourdough toasted with some cheese or avocado, or the white sourdough with peanut butter and jam.
Our fluffy Spring bread is made with both our sourdough starter and some conventional yeast, so it also has some of the properties of our sourdoughs, but its texture is much softer and lighter. This bread is great for sandwiches, grilled cheese, or french toast for breakfast!
1. Young, Linda; Cauvain, Stanley P. (2007). Technology of Breadmaking. Berlin: Springer. p. 79.
2. Weibiao Zhou; Nantawan Therdthai (2012). Y.H. Hui, E. Özgül Evranuz, eds. "Fermented Bread". Handbook of Plant-Based Fermented Food and Beverage Technology (2 ed.). CRC Press: 477–526.