Previously I have written about what constitutes the wild leaven used in sourdough bread baking. I now want to explore how it works and why I bother using it at all. After all, it takes longer to make bread this way. The results of the extra time, however, provide some of the most compelling reasons to make and eat sourdough bread.
In 1961 the Chorleywood Bread Process was developed by the British Baking Industries’s Research Association in Chorleywood, UK. It allowed for bread to be produced en masse and quickly. As with any new technology, however, it has its drawbacks. The process requires added fats, anti fungal agents, and chemical improvers. According to Daniel Stevens (2009) the short fermentation makes the wheat harder to digest and this, along with the many additives, is partly to blame for greater gluten intolerances and bread allergies. The sourdough process, in contrast, facilitates the partial breakdown of gluten, making it easier to digest. Additionally, according to Pollan (2013), the sourdough fermentation process results in the body absorbing the sugars in white flour more slowly thus reducing “dangerous spikes in insulin that refined carbohydrates can cause”.
So it seems sourdough bread not only has a distinctive taste, it is better for our bodies too.
The sourdough fermenting process at Bangor Bakehouse begins with refreshing or awakening the wild starter culture that has been sleeping in the fridge. It is fed with water and wholemeal rye flour with half being put back in the fridge and the other half left at room temperature for 12 hours. The refreshed starter is used to make the pre-ferments. These are mixtures of flour, water, and starter that are left for another 12 hours to ferment and increase the micro-organism activity. The final dough ingredients are then mixed with the pre-ferments and kneaded or folded. The resulting dough is then shaped and set aside for, what is called, the final fermentation (although it’s not really the final). The real final fermentation takes place in the oven as the organisms in the dough increase their activity rapidly in the heat to give the loaf its final shape and size. This is called the oven bloom and it lasts until the terminal temperature is reached.
And there you have it, a loaf brought to you by millions of micro-organisms, a little human manipulation, time, and oven heat.
Next time I’ll be writing about the Wet side of things i.e. what proportion of water to add to the flour and what this means to the baker and the bread.