Basics of Sourdough

Want to start making sourdough bread? I decided to compile this sourdough digest to help people understand the basics of sourdough. Many people these days are spending more time at home and looking for something new to do. There are countless of instagram and facebook pictures displaying people's wonderful overflowing starter. A few months ago, during Covid lockdown, you could not get any bread flour at the grocery stores and all bread making supplies on Amazon were back-ordered. Everyone seemed to be taking up sourdough bread making during the pandemic.

Making sourdough bread is very rewarding but can be somewhat daunting. However, with an understanding of the basics of sourdough, it will be a less intimidating. I started my sourdough adventure more out of a need rather than a desire after being diagnosed with pre-diabetes in 2018. After doing extensive research, I was hooked because of what I learned as well as seeing results in my family and friends with health challenges. Many of my sourdough recipes incorporate both ingredients and techniques that maximizes nutrition and minimizes gluten and carb. to make the end product healthier. I have organized this page to hopefully give you a comprehensive overview of the basics of sourdough.

Why Sourdough?

What is sourdough?

Sourdough is a natural leavening agent used for making breads. A ‘starter’ is composed of fermented flour, water, micro-organisms, lactic acid bacteria and yeasts naturally present in the flour, air and on your hands! According to the Puratos sourdough library, over 1100 strains of micro-organisms have been recorded. As a result, natural starters produce breads that have unique flavors depending on the micro-organisms makeup and the environment in which they thrive. Many Americans think sourdough dates back to the Gold Rush when the Boudin family started to produce the famous San Francisco Boudin sourdough bread. Research shows that sourdough can be traced back to Ancient Egyptian civilizations around 1500 BC. I was fascinated by this article on yeast and lactic acid bacteria in sourdough. Basically, lactic acid bacteria is abundant in sourdough than in commercial yeast and its presence as well as the sourdough bread making technique has many benefits.

Benefits of sourdough

Some people like sourdough because of the flavor, texture or nutritional benefits. For me, I had to do research to determine whether this whole sourdough thing was worth the time and effort and my findings were eye opening.

Unique flavor profiles

Because sourdough bread is made from a "live" starter whose flavor profile is dependent on its environment, these breads have their own unique and interesting taste. The longer the starter ferments, the more sour the dough. So, as a baker, you can decide and adjust the tanginess of your bread just by fermenting your dough longer. There have been many scientific studies done where the base was the standard bakers yeast bread compared to sourdough breads. NONE of the participants chose the breads made with bakers yeast for the taste and texture.

More nutritious

Lactobacillus

As mentioned above, sourdough starter is made up of active bacteria and yeasts. The most common bacteria found in sourdough all over the world is lactobacillus or lactic acid bacteria (LAB). What does the presence of lactobacillus do in the bread? Most flours (wheat bran) contain phytic acid. This acid binds to important minerals like calcium, zinc, iron, and magnesium. It has been proven that LAB, during the fermentation process produces a more suitable pH condition for the degradation of phytic acid, freeing up the minerals and making them more available for our bodies to absorb. See Effects of natural starters used for sourdough bread in Morocco on phytate biodegradation.
The sourdough baking process

I underscore "during the fermentation process," because it's not just the mere presence of the lactobacillus in the starter, but it's during this fermentation process when the phytates degrade. The longer the dough is allowed to ferment, the more time the lactobacilli have to do their work. I mention this because many commercial bakeries call their items "sourdough". However, they just add an acetic acid to make their dough sour. They may also add both sourdough starter plus bakers yeast to speed up fermentation. So, read the labels! You may think you're getting sourdough, but you're not getting the benefits of sourdough.

Homemade sourdough and some of my other sourdough recipes take over 12 hours to make. Most of that time is in the proofing (fermentation) of the dough. This is an important aspect of the recipe as this is when all the bio-chemical activity is occurring. I also gleaned from my readings that phytate biodegradation happens the most at 25 degrees Celcius or 77 degrees Fahrenheit. So, keep this in mind when doing bulk fermentation.

Lower glycemic index

There is an interesting study on Sourdough fermentation as a tool for the manufacture of low-glycemic index white wheat bread enriched in dietary fibre. I tried to do this experiment myself in my own kitchen and compared my blood sugar levels after eating my sourdough bread and store bought bread. The results were consistent with that of the study. I had a lower blood sugar level after eating sourdough vs. store bought regular bakers yeast bread.

Lower gluten

Another scientific study that was done proved that lactobacillus does decrease the amount of gluten in the bread. Although many studies show conflicting results as to whether sourdough breads could be considered gluten-free, I would say that sourdough breads are acceptable for people who are gluten intolerant, but not for those who have Celiac disease. This study was interesting because it mentioned that those gluten-free breads that people buy may help if you have Celiac disease, but the starches that make up the gluten-free "flour" is void of minerals and nutrients. Something worth thinking about!

After pouring over copious studies and thinking about the nature of sourdough and its interactions with its environment, I realize how most baked goods can be tweaked in ingredients and technique to not only lower the glycemic index and gluten but also increase the nutritional content of the end product. This however, does require more time in the baking process, but well worth it for your health's sake.